WIP OpenDream Support

src/DMAPI/tgs.dm

@@ -1,6 +1,6 @@
 // tgstation-server DMAPI
 
-#define TGS_DMAPI_VERSION "6.5.3"
+#define TGS_DMAPI_VERSION "6.6.0"
 
 // All functions and datums outside this document are subject to change with any version and should not be relied on.
 
@@ -73,11 +73,11 @@
 #define TGS_EVENT_REPO_MERGE_PULL_REQUEST 3
 /// Before the repository makes a sychronize operation. Parameters: Absolute repostiory path.
 #define TGS_EVENT_REPO_PRE_SYNCHRONIZE 4
-/// Before a BYOND install operation begins. Parameters: [/datum/tgs_version] of the installing BYOND.
+/// Before a BYOND install operation begins. Parameters: [/datum/tgs_version] of the installing BYOND, engine type of the installing BYOND.
 #define TGS_EVENT_BYOND_INSTALL_START 5
 /// When a BYOND install operation fails. Parameters: Error message
 #define TGS_EVENT_BYOND_INSTALL_FAIL 6
-/// When the active BYOND version changes.  Parameters: (Nullable) [/datum/tgs_version] of the current BYOND, [/datum/tgs_version] of the new BYOND.
+/// When the active BYOND version changes. Parameters: (Nullable) [/datum/tgs_version] of the current BYOND, [/datum/tgs_version] of the new BYOND, engine type of the current BYOND, engine type of the new BYOND.
 #define TGS_EVENT_BYOND_ACTIVE_VERSION_CHANGE 7
 /// When the compiler starts running. Parameters: Game directory path, origin commit SHA.
 #define TGS_EVENT_COMPILE_START 8
@@ -129,6 +129,11 @@
 /// DreamDaemon Ultrasafe security level.
 #define TGS_SECURITY_ULTRASAFE 2
 
+/// The Build Your Own Net Dream engine.
+#define TGS_ENGINE_TYPE_BYOND 0
+/// The OpenDream engine.
+#define TGS_ENGINE_TYPE_OPENDREAM 1
+
 //REQUIRED HOOKS
 
 /**

src/Tgstation.Server.Api/Models/EngineType.cs

@@ -0,0 +1,18 @@
+namespace Tgstation.Server.Api.Models
+{
+	/// <summary>
+	/// The type of engine the codebase is using.
+	/// </summary>
+	public enum EngineType
+	{
+		/// <summary>
+		/// Build your own net dream,
+		/// </summary>
+		Byond,
+
+		/// <summary>
+		/// The OpenDream BYOND reimplementation.
+		/// </summary>
+		OpenDream,
+	}
+}

src/Tgstation.Server.Api/Models/Internal/ByondVersion.cs

@@ -0,0 +1,109 @@
+using System;
+using System.ComponentModel.DataAnnotations;
+using System.Linq;
+
+namespace Tgstation.Server.Api.Models.Internal
+{
+	/// <summary>
+	/// Information about a Byond installation.
+	/// </summary>
+	public class ByondVersion : IEquatable<ByondVersion>
+	{
+		/// <summary>
+		/// The <see cref="EngineType"/>.
+		/// </summary>
+		[RequestOptions(FieldPresence.Required)]
+		public EngineType? Engine { get; set; }
+
+		/// <summary>
+		/// The <see cref="System.Version"/> of the engine.
+		/// </summary>
+		[ResponseOptions]
+		public Version? Version { get; set; }
+
+		/// <summary>
+		/// The git committish of the <see cref="Version"/>. On response, this will always be a commit SHA.
+		/// </summary>
+		[ResponseOptions]
+		[StringLength(Limits.MaximumCommitShaLength)]
+		public string? SourceCommittish { get; set; }
+
+		/// <summary>
+		/// Parses a stringified <see cref="ByondVersion"/>.
+		/// </summary>
+		/// <param name="input">The input <see cref="string"/>.</param>
+		/// <param name="byondVersion">The output <see cref="ByondVersion"/>.</param>
+		/// <returns><see langword="true"/> if parsing was successful, <see langword="false"/> otherwise.</returns>
+		public static bool TryParse(string input, out ByondVersion? byondVersion)
+		{
+			if (input == null)
+				throw new ArgumentNullException(nameof(input));
+
+			var splits = input.Split(new char[] { '-' }, StringSplitOptions.RemoveEmptyEntries);
+			byondVersion = null;
+
+			if (splits.Length > 2)
+				return false;
+
+			EngineType engine;
+			if (splits.Length > 1)
+			{
+				if (!Enum.TryParse(splits[0], out engine))
+					return false;
+			}
+			else
+				engine = EngineType.Byond;
+
+			if (!Version.TryParse(splits.Last(), out var version))
+				return false;
+
+			byondVersion = new ByondVersion
+			{
+				Engine = engine,
+				Version = version,
+			};
+			return true;
+		}
+
+		/// <summary>
+		/// Initializes a new instance of the <see cref="ByondVersion"/> class.
+		/// </summary>
+		public ByondVersion()
+		{
+		}
+
+		/// <summary>
+		/// Initializes a new instance of the <see cref="ByondVersion"/> class.
+		/// </summary>
+		/// <param name="other">The <see cref="ByondVersion"/> to copy.</param>
+		public ByondVersion(ByondVersion other)
+		{
+			if (other == null)
+				throw new ArgumentNullException(nameof(other));
+
+			Version = other.Version;
+			Engine = other.Engine;
+			SourceCommittish = other.SourceCommittish;
+		}
+
+		/// <inheritdoc />
+		public bool Equals(ByondVersion other)
+		{
+			// https://github.com/dotnet/roslyn-analyzers/issues/2875
+#pragma warning disable CA1062 // Validate arguments of public methods
+			return other!.Version == Version
+				&& other.Engine == Engine;
+#pragma warning restore CA1062 // Validate arguments of public methods
+		}
+
+		/// <inheritdoc />
+		public override bool Equals(object obj)
+			=> obj is ByondVersion other && Equals(other);
+
+		/// <inheritdoc />
+		public override string ToString() => $"{(Engine != EngineType.Byond ? $"{Engine}-" : String.Empty)}{Version}"; // BYOND isn't display for backwards compatibility. SourceCommittish is not included
+
+		/// <inheritdoc />
+		public override int GetHashCode() => ToString().GetHashCode();
+	}
+}

src/Tgstation.Server.Api/Models/Request/ByondVersionDeleteRequest.cs

@@ -1,16 +1,13 @@
 using System;
 
+using Tgstation.Server.Api.Models.Internal;
+
 namespace Tgstation.Server.Api.Models.Request
 {
 	/// <summary>
 	/// A request to delete a specific <see cref="Version"/>.
 	/// </summary>
-	public class ByondVersionDeleteRequest
+	public class ByondVersionDeleteRequest : ByondVersion
 	{
-		/// <summary>
-		/// The BYOND version to install.
-		/// </summary>
-		[RequestOptions(FieldPresence.Required)]
-		public Version? Version { get; set; }
 	}
 }

src/Tgstation.Server.Api/Models/Request/ByondVersionRequest.cs

@@ -1,13 +1,22 @@
-namespace Tgstation.Server.Api.Models.Request
+using System;
+
+using Tgstation.Server.Api.Models.Internal;
+
+namespace Tgstation.Server.Api.Models.Request
 {
 	/// <summary>
-	/// A request to install a BYOND <see cref="ByondVersionDeleteRequest.Version"/>.
+	/// A request to install a <see cref="ByondVersion"/>.
 	/// </summary>
-	public sealed class ByondVersionRequest : ByondVersionDeleteRequest
+	public sealed class ByondVersionRequest : ByondVersion
 	{
 		/// <summary>
 		/// If a custom BYOND version is to be uploaded.
 		/// </summary>
 		public bool? UploadCustomZip { get; set; }
+
+		/// <summary>
+		/// The remote repository for non-<see cref="EngineType.Byond"/> <see cref="EngineType"/>s. By default, this is the original git repository of the target <see cref="EngineType"/>.
+		/// </summary>
+		public Uri? SourceRepository { get; set; }
 	}
 }

src/Tgstation.Server.Api/Models/Response/ByondResponse.cs

@@ -1,16 +1,19 @@
-using System;
+using Tgstation.Server.Api.Models.Internal;
 
 namespace Tgstation.Server.Api.Models.Response
 {
 	/// <summary>
-	/// Represents an installed BYOND <see cref="Version"/>.
+	/// Represents an installed <see cref="ByondVersion"/>.
 	/// </summary>
-	public sealed class ByondResponse
+	public sealed class ByondResponse : ByondVersion
 	{
 		/// <summary>
-		/// The installed BYOND <see cref="System.Version"/>. BYOND itself only considers the <see cref="Version.Major"/> and <see cref="Version.Minor"/> numbers. TGS uses the <see cref="Version.Build"/> number to represent installed custom versions.
+		/// Initializes a new instance of the <see cref="ByondResponse"/> class.
 		/// </summary>
-		[ResponseOptions]
-		public Version? Version { get; set; }
+		/// <param name="byondVersion">The <see cref="ByondVersion"/> to copy.</param>
+		public ByondResponse(ByondVersion byondVersion)
+			: base(byondVersion)
+		{
+		}
 	}
 }

src/Tgstation.Server.Api/Models/Response/CompileJobResponse.cs

@@ -1,9 +1,11 @@
 using System;
 
+using Tgstation.Server.Api.Models.Internal;
+
 namespace Tgstation.Server.Api.Models.Response
 {
 	/// <inheritdoc />
-	public sealed class CompileJobResponse : Internal.CompileJob
+	public sealed class CompileJobResponse : CompileJob
 	{
 		/// <summary>
 		/// The <see cref="Job"/> relating to this job.
@@ -16,9 +18,14 @@ namespace Tgstation.Server.Api.Models.Response
 		public RevisionInformation? RevisionInformation { get; set; }
 
 		/// <summary>
-		/// The <see cref="ByondResponse.Version"/> the <see cref="CompileJobResponse"/> was made with.
+		/// The <see cref="ByondVersion.Version"/> the <see cref="CompileJobResponse"/> was made with.
 		/// </summary>
-		public Version? ByondVersion { get; set; }
+		public ByondVersion? ByondVersion { get; set; }
+
+		/// <summary>
+		/// The <see cref="ByondVersion.Engine"/> the <see cref="CompileJobResponse"/> was made with.
+		/// </summary>
+		public EngineType? Engine { get; set; }
 
 		/// <summary>
 		/// The origin <see cref="Uri"/> of the repository the compile job was built from.

src/Tgstation.Server.Api/Rights/ByondRights.cs

@@ -14,33 +14,43 @@ namespace Tgstation.Server.Api.Rights
 		None = 0,
 
 		/// <summary>
-		/// User may view the active installed BYOND version.
+		/// User may view the active installed engine versions.
 		/// </summary>
 		ReadActive = 1 << 0,
 
 		/// <summary>
-		/// User may list all installed BYOND versions.
+		/// User may list all installed engine versions.
 		/// </summary>
 		ListInstalled = 1 << 1,
 
 		/// <summary>
-		/// User may install official BYOND versions or change the active BYOND version.
+		/// User may install official <see cref="Models.EngineType.Byond"/> versions or change the active <see cref="Models.EngineType.Byond"/> version.
 		/// </summary>
-		InstallOfficialOrChangeActiveVersion = 1 << 2,
+		InstallOfficialOrChangeActiveByondVersion = 1 << 2,
 
 		/// <summary>
-		/// User may cancel BYOND installation job.
+		/// User may cancel an engine installation job.
 		/// </summary>
 		CancelInstall = 1 << 3,
 
 		/// <summary>
-		/// User may upload and activate custom BYOND builds.
+		/// User may upload and activate custom <see cref="Models.EngineType.Byond"/> builds.
 		/// </summary>
-		InstallCustomVersion = 1 << 4,
+		InstallCustomByondVersion = 1 << 4,
 
 		/// <summary>
-		/// User may delete non-active BYOND builds.
+		/// User may delete non-active engine builds.
 		/// </summary>
 		DeleteInstall = 1 << 5,
+
+		/// <summary>
+		/// User may install official <see cref="Models.EngineType.OpenDream"/> versions or change the active <see cref="Models.EngineType.OpenDream"/> version.
+		/// </summary>
+		InstallOfficialOrChangeActiveOpenDreamVersion = 1 << 6,
+
+		/// <summary>
+		/// User may activate custom <see cref="Models.EngineType.OpenDream"/> builds via zip upload or custom git committish.
+		/// </summary>
+		InstallCustomOpenDreamVersion = 1 << 7,
 	}
 }

src/Tgstation.Server.Host/Components/Byond/ByondExecutableLock.cs

@@ -1,28 +0,0 @@
-using System;
-
-using Tgstation.Server.Host.Utils;
-
-namespace Tgstation.Server.Host.Components.Byond
-{
-	/// <inheritdoc cref="IByondExecutableLock" />
-	sealed class ByondExecutableLock : ReferenceCounter<ByondInstallation>, IByondExecutableLock
-	{
-		/// <inheritdoc />
-		public Version Version => Instance.Version;
-
-		/// <inheritdoc />
-		public string DreamDaemonPath => Instance.DreamDaemonPath;
-
-		/// <inheritdoc />
-		public string DreamMakerPath => Instance.DreamMakerPath;
-
-		/// <inheritdoc />
-		public bool SupportsCli => Instance.SupportsCli;
-
-		/// <inheritdoc />
-		public bool SupportsMapThreads => Instance.SupportsMapThreads;
-
-		/// <inheritdoc />
-		public void DoNotDeleteThisSession() => DangerousDropReference();
-	}
-}

src/Tgstation.Server.Host/Components/Byond/ByondInstallation.cs

@@ -1,54 +1,148 @@
 using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Linq;
 using System.Threading.Tasks;
+using System.Web;
+
+using Tgstation.Server.Api.Models;
+using Tgstation.Server.Api.Models.Internal;
+using Tgstation.Server.Host.Components.Deployment;
 
 namespace Tgstation.Server.Host.Components.Byond
 {
-	/// <inheritdoc />
-	sealed class ByondInstallation : IByondInstallation
+	/// <summary>
+	/// Implementation of <see cref="IEngineInstallation"/> for <see cref="EngineType.Byond"/>.
+	/// </summary>
+	sealed class ByondInstallation : IEngineInstallation
 	{
 		/// <inheritdoc />
-		public Version Version { get; }
+		public ByondVersion Version { get; }
 
 		/// <inheritdoc />
-		public string DreamDaemonPath { get; }
+		public string ServerExePath { get; }
 
 		/// <inheritdoc />
-		public string DreamMakerPath { get; }
+		public string CompilerExePath { get; }
 
 		/// <inheritdoc />
-		public bool SupportsCli { get; }
+		public bool PromptsForNetworkAccess { get; }
 
 		/// <inheritdoc />
-		public bool SupportsMapThreads { get; }
+		public bool HasStandardOutput { get; }
+
+		/// <inheritdoc />
+		public Task InstallationTask { get; }
 
 		/// <summary>
-		/// The <see cref="Task"/> that completes when the BYOND version finished installing.
+		/// If map threads are supported by the <see cref="Version"/>.
 		/// </summary>
-		public Task InstallationTask { get; }
+		readonly bool supportsMapThreads;
+
+		/// <summary>
+		/// Change a given <paramref name="securityLevel"/> into the appropriate DreamDaemon command line word.
+		/// </summary>
+		/// <param name="securityLevel">The <see cref="DreamDaemonSecurity"/> level to change.</param>
+		/// <returns>A <see cref="string"/> representation of the command line parameter.</returns>
+		static string SecurityWord(DreamDaemonSecurity securityLevel)
+		{
+			return securityLevel switch
+			{
+				DreamDaemonSecurity.Safe => "safe",
+				DreamDaemonSecurity.Trusted => "trusted",
+				DreamDaemonSecurity.Ultrasafe => "ultrasafe",
+				_ => throw new ArgumentOutOfRangeException(nameof(securityLevel), securityLevel, String.Format(CultureInfo.InvariantCulture, "Bad DreamDaemon security level: {0}", securityLevel)),
+			};
+		}
+
+		/// <summary>
+		/// Change a given <paramref name="visibility"/> into the appropriate DreamDaemon command line word.
+		/// </summary>
+		/// <param name="visibility">The <see cref="DreamDaemonVisibility"/> level to change.</param>
+		/// <returns>A <see cref="string"/> representation of the command line parameter.</returns>
+		static string VisibilityWord(DreamDaemonVisibility visibility)
+		{
+			return visibility switch
+			{
+				DreamDaemonVisibility.Public => "public",
+				DreamDaemonVisibility.Private => "private",
+				DreamDaemonVisibility.Invisible => "invisible",
+				_ => throw new ArgumentOutOfRangeException(nameof(visibility), visibility, String.Format(CultureInfo.InvariantCulture, "Bad DreamDaemon visibility level: {0}", visibility)),
+			};
+		}
 
 		/// <summary>
 		/// Initializes a new instance of the <see cref="ByondInstallation"/> class.
 		/// </summary>
 		/// <param name="installationTask">The value of <see cref="InstallationTask"/>.</param>
 		/// <param name="version">The value of <see cref="Version"/>.</param>
-		/// <param name="dreamDaemonPath">The value of <see cref="DreamDaemonPath"/>.</param>
-		/// <param name="dreamMakerPath">The value of <see cref="DreamMakerPath"/>.</param>
-		/// <param name="supportsCli">The value of <see cref="SupportsCli"/>.</param>
-		/// <param name="supportsMapThreads">The value of <see cref="SupportsMapThreads"/>.</param>
+		/// <param name="dreamDaemonPath">The value of <see cref="ServerExePath"/>.</param>
+		/// <param name="dreamMakerPath">The value of <see cref="CompilerExePath"/>.</param>
+		/// <param name="supportsCli">If a CLI application is being used.</param>
+		/// <param name="supportsMapThreads">The value of <see cref="supportsMapThreads"/>.</param>
 		public ByondInstallation(
 			Task installationTask,
-			Version version,
+			ByondVersion version,
 			string dreamDaemonPath,
 			string dreamMakerPath,
 			bool supportsCli,
 			bool supportsMapThreads)
 		{
 			InstallationTask = installationTask ?? throw new ArgumentNullException(nameof(installationTask));
+			ArgumentNullException.ThrowIfNull(version);
+
+			if (version.Engine.Value != EngineType.Byond)
+				throw new ArgumentException($"Invalid EngineType: {version.Engine.Value}", nameof(version));
+
 			Version = version ?? throw new ArgumentNullException(nameof(version));
-			DreamDaemonPath = dreamDaemonPath ?? throw new ArgumentNullException(nameof(dreamDaemonPath));
-			DreamMakerPath = dreamMakerPath ?? throw new ArgumentNullException(nameof(dreamMakerPath));
-			SupportsCli = supportsCli;
-			SupportsMapThreads = supportsMapThreads;
+			ServerExePath = dreamDaemonPath ?? throw new ArgumentNullException(nameof(dreamDaemonPath));
+			CompilerExePath = dreamMakerPath ?? throw new ArgumentNullException(nameof(dreamMakerPath));
+			HasStandardOutput = supportsCli;
+			PromptsForNetworkAccess = !supportsCli;
+			this.supportsMapThreads = supportsMapThreads;
 		}
+
+		/// <inheritdoc />
+		public string FormatServerArguments(
+			IDmbProvider dmbProvider,
+			IReadOnlyDictionary<string, string> parameters,
+			DreamDaemonLaunchParameters launchParameters,
+			string logFilePath)
+		{
+			ArgumentNullException.ThrowIfNull(dmbProvider);
+			ArgumentNullException.ThrowIfNull(parameters);
+			ArgumentNullException.ThrowIfNull(launchParameters);
+
+			var parametersString = String.Join('&', parameters.Select(kvp => $"{HttpUtility.UrlEncode(kvp.Key)}={HttpUtility.UrlEncode(kvp.Value)}"));
+
+			if (!String.IsNullOrEmpty(launchParameters.AdditionalParameters))
+				parametersString = $"{parametersString}&{launchParameters.AdditionalParameters}";
+
+			var arguments = String.Format(
+				CultureInfo.InvariantCulture,
+				"{0} -port {1} -ports 1-65535 {2}-close -verbose -{3} -{4}{5}{6}{7} -params \"{8}\"",
+				dmbProvider.DmbName,
+				launchParameters.Port.Value,
+				launchParameters.AllowWebClient.Value
+					? "-webclient "
+					: String.Empty,
+				SecurityWord(launchParameters.SecurityLevel.Value),
+				VisibilityWord(launchParameters.Visibility.Value),
+				logFilePath != null
+					? $" -logself -log {logFilePath}"
+					: String.Empty, // DD doesn't output anything if -logself is set???
+				launchParameters.StartProfiler.Value
+					? " -profile"
+					: String.Empty,
+				supportsMapThreads && launchParameters.MapThreads.Value != 0
+					? $" -map-threads {launchParameters.MapThreads.Value}"
+					: String.Empty,
+				parametersString);
+			return arguments;
+		}
+
+		/// <inheritdoc />
+		public string FormatCompilerArguments(string dmePath)
+			=> $"-clean \"{dmePath ?? throw new ArgumentNullException(nameof(dmePath))}\"";
 	}
 }

src/Tgstation.Server.Host/Components/Byond/ByondInstallerBase.cs

@@ -6,6 +6,7 @@ using System.Threading.Tasks;
 
 using Microsoft.Extensions.Logging;
 
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Host.IO;
 
 namespace Tgstation.Server.Host.Components.Byond
@@ -24,10 +25,10 @@ namespace Tgstation.Server.Host.Components.Byond
 		public static Version MapThreadsVersion => new (515, 1609);
 
 		/// <inheritdoc />
-		public abstract string DreamMakerName { get; }
+		public abstract string CompilerName { get; }
 
 		/// <inheritdoc />
-		public abstract string PathToUserByondFolder { get; }
+		public abstract string PathToUserFolder { get; }
 
 		/// <summary>
 		/// Gets the URL formatter string for downloading a byond version of {0:Major} {1:Minor}.
@@ -63,7 +64,7 @@ namespace Tgstation.Server.Host.Components.Byond
 		}
 
 		/// <inheritdoc />
-		public abstract string GetDreamDaemonName(Version version, out bool supportsCli, out bool supportsMapThreads);
+		public abstract string GetDreamDaemonName(ByondVersion version, out bool supportsCli, out bool supportsMapThreads);
 
 		/// <inheritdoc />
 		public async Task CleanCache(CancellationToken cancellationToken)
@@ -73,7 +74,7 @@ namespace Tgstation.Server.Host.Components.Byond
 				Logger.LogDebug("Cleaning BYOND cache...");
 				await IOManager.DeleteDirectory(
 					IOManager.ConcatPath(
-						PathToUserByondFolder,
+						PathToUserFolder,
 						CacheDirectoryName),
 					cancellationToken);
 			}
@@ -84,18 +85,18 @@ namespace Tgstation.Server.Host.Components.Byond
 		}
 
 		/// <inheritdoc />
-		public abstract ValueTask InstallByond(Version version, string path, CancellationToken cancellationToken);
+		public abstract ValueTask InstallByond(ByondVersion version, string path, CancellationToken cancellationToken);
 
 		/// <inheritdoc />
-		public abstract ValueTask UpgradeInstallation(Version version, string path, CancellationToken cancellationToken);
+		public abstract ValueTask UpgradeInstallation(ByondVersion version, string path, CancellationToken cancellationToken);
 
 		/// <inheritdoc />
-		public async ValueTask<MemoryStream> DownloadVersion(Version version, CancellationToken cancellationToken)
+		public async ValueTask<MemoryStream> DownloadVersion(ByondVersion version, CancellationToken cancellationToken)
 		{
 			ArgumentNullException.ThrowIfNull(version);
 
-			Logger.LogTrace("Downloading BYOND version {major}.{minor}...", version.Major, version.Minor);
-			var url = String.Format(CultureInfo.InvariantCulture, ByondRevisionsUrlTemplate, version.Major, version.Minor);
+			Logger.LogTrace("Downloading BYOND version {major}.{minor}...", version.Version.Major, version.Version.Minor);
+			var url = String.Format(CultureInfo.InvariantCulture, ByondRevisionsUrlTemplate, version.Version.Major, version.Version.Minor);
 
 			await using var download = fileDownloader.DownloadFile(new Uri(url), null);
 			await using var buffer = new BufferedFileStreamProvider(

src/Tgstation.Server.Host/Components/Byond/ByondManager.cs

@@ -10,6 +10,7 @@ using System.Threading.Tasks;
 using Microsoft.Extensions.Logging;
 
 using Tgstation.Server.Api.Models;
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Common.Extensions;
 using Tgstation.Server.Host.Components.Events;
 using Tgstation.Server.Host.IO;
@@ -47,10 +48,10 @@ namespace Tgstation.Server.Host.Components.Byond
 		const string ActiveVersionFileName = "ActiveVersion.txt";
 
 		/// <inheritdoc />
-		public Version ActiveVersion { get; private set; }
+		public ByondVersion ActiveVersion { get; private set; }
 
 		/// <inheritdoc />
-		public IReadOnlyList<Version> InstalledVersions
+		public IReadOnlyList<ByondVersion> InstalledVersions
 		{
 			get
 			{
@@ -87,7 +88,7 @@ namespace Tgstation.Server.Host.Components.Byond
 		/// <summary>
 		/// Map of byond <see cref="Version"/>s to <see cref="Task"/>s that complete when they are installed.
 		/// </summary>
-		readonly Dictionary<Version, ReferenceCountingContainer<ByondInstallation, ByondExecutableLock>> installedVersions;
+		readonly Dictionary<ByondVersion, ReferenceCountingContainer<IEngineInstallation, EngineExecutableLock>> installedVersions;
 
 		/// <summary>
 		/// The <see cref="SemaphoreSlim"/> for changing or deleting the active BYOND version.
@@ -103,11 +104,14 @@ namespace Tgstation.Server.Host.Components.Byond
 		/// Validates a given <paramref name="version"/> parameter.
 		/// </summary>
 		/// <param name="version">The <see cref="Version"/> to validate.</param>
-		static void CheckVersionParameter(Version version)
+		static void CheckVersionParameter(ByondVersion version)
 		{
 			ArgumentNullException.ThrowIfNull(version);
 
-			if (version.Build == 0)
+			if (!version.Engine.HasValue)
+				throw new InvalidOperationException("version.Engine cannot be null!");
+
+			if (version.Version.Build == 0)
 				throw new InvalidOperationException("version.Build cannot be 0!");
 		}
 
@@ -125,7 +129,7 @@ namespace Tgstation.Server.Host.Components.Byond
 			this.eventConsumer = eventConsumer ?? throw new ArgumentNullException(nameof(eventConsumer));
 			this.logger = logger ?? throw new ArgumentNullException(nameof(logger));
 
-			installedVersions = new Dictionary<Version, ReferenceCountingContainer<ByondInstallation, ByondExecutableLock>>();
+			installedVersions = new Dictionary<ByondVersion, ReferenceCountingContainer<IEngineInstallation, EngineExecutableLock>>();
 			changeDeleteSemaphore = new SemaphoreSlim(1);
 			activeVersionChanged = new TaskCompletionSource();
 		}
@@ -136,7 +140,7 @@ namespace Tgstation.Server.Host.Components.Byond
 		/// <inheritdoc />
 		public async ValueTask ChangeVersion(
 			JobProgressReporter progressReporter,
-			Version version,
+			ByondVersion version,
 			Stream customVersionStream,
 			bool allowInstallation,
 			CancellationToken cancellationToken)
@@ -154,7 +158,10 @@ namespace Tgstation.Server.Host.Components.Byond
 					cancellationToken);
 
 				// We reparse the version because it could be changed after a custom install.
-				version = installLock.Version;
+				version = new ByondVersion(version)
+				{
+					Version = installLock.Version.Version,
+				};
 
 				var stringVersion = version.ToString();
 				await ioManager.WriteAllBytes(ActiveVersionFileName, Encoding.UTF8.GetBytes(stringVersion), cancellationToken);
@@ -177,7 +184,7 @@ namespace Tgstation.Server.Host.Components.Byond
 		}
 
 		/// <inheritdoc />
-		public async ValueTask<IByondExecutableLock> UseExecutables(Version requiredVersion, string trustDmbFullPath, CancellationToken cancellationToken)
+		public async ValueTask<IEngineExecutableLock> UseExecutables(ByondVersion requiredVersion, string trustDmbFullPath, CancellationToken cancellationToken)
 		{
 			logger.LogTrace(
 				"Acquiring lock on BYOND version {version}...",
@@ -205,7 +212,7 @@ namespace Tgstation.Server.Host.Components.Byond
 		}
 
 		/// <inheritdoc />
-		public async ValueTask DeleteVersion(JobProgressReporter progressReporter, Version version, CancellationToken cancellationToken)
+		public async ValueTask DeleteVersion(JobProgressReporter progressReporter, ByondVersion version, CancellationToken cancellationToken)
 		{
 			ArgumentNullException.ThrowIfNull(progressReporter);
 
@@ -213,15 +220,18 @@ namespace Tgstation.Server.Host.Components.Byond
 
 			logger.LogTrace("DeleteVersion {version}", version);
 
-			if (version == ActiveVersion)
+			if (version.Equals(ActiveVersion))
 				throw new JobException(ErrorCode.ByondCannotDeleteActiveVersion);
 
-			ReferenceCountingContainer<ByondInstallation, ByondExecutableLock> container;
+			ReferenceCountingContainer<IEngineInstallation, EngineExecutableLock> container;
 			lock (installedVersions)
 				if (!installedVersions.TryGetValue(version, out container))
-					return; // already "deleted"
+				{
+					logger.LogTrace("Version {version} already deleted.", version);
+					return;
+				}
 
-			logger.LogInformation("Deleting BYOND version {version}...", version);
+			logger.LogInformation("Deleting version {version}...", version);
 			progressReporter.StageName = "Waiting for version to not be in use...";
 			while (true)
 			{
@@ -238,7 +248,7 @@ namespace Tgstation.Server.Host.Components.Byond
 					.WaitAsync(cancellationToken);
 
 				if (containerTask.IsCompleted)
-					logger.LogTrace("All BYOND locks for {version} are gone", version);
+					logger.LogTrace("All locks for version {version} are gone", version);
 
 				using (await SemaphoreSlimContext.Lock(changeDeleteSemaphore, cancellationToken))
 				{
@@ -252,7 +262,7 @@ namespace Tgstation.Server.Host.Components.Byond
 						proceed = container.OnZeroReferences.IsCompleted;
 						if (proceed)
 							if (!installedVersions.TryGetValue(version, out var newerContainer))
-								logger.LogWarning("Unable to remove BYOND installation {version} from list! Is there a duplicate job running?", version);
+								logger.LogWarning("Unable to remove engine installation {version} from list! Is there a duplicate job running?", version);
 							else
 							{
 								if (container != newerContainer)
@@ -291,6 +301,13 @@ namespace Tgstation.Server.Host.Components.Byond
 			}
 		}
 
+		/// <inheritdoc />
+		public async ValueTask EnsureEngineSource(Uri source, EngineType engine, CancellationToken cancellationToken)
+		{
+			await Task.Yield();
+			throw new NotImplementedException();
+		}
+
 		/// <inheritdoc />
 		public async Task StartAsync(CancellationToken cancellationToken)
 		{
@@ -302,7 +319,7 @@ namespace Tgstation.Server.Host.Components.Byond
 
 			var activeVersionBytesTask = GetActiveVersion();
 
-			var byondDir = byondInstaller.PathToUserByondFolder;
+			var byondDir = byondInstaller.PathToUserFolder;
 			if (byondDir != null)
 				using (await SemaphoreSlimContext.Lock(UserFilesSemaphore, cancellationToken))
 				{
@@ -328,7 +345,7 @@ namespace Tgstation.Server.Host.Components.Byond
 			await ioManager.CreateDirectory(DefaultIOManager.CurrentDirectory, cancellationToken);
 			var directories = await ioManager.GetDirectories(DefaultIOManager.CurrentDirectory, cancellationToken);
 
-			var installedVersionPaths = new Dictionary<string, Version>();
+			var installedVersionPaths = new Dictionary<string, ByondVersion>();
 
 			async ValueTask ReadVersion(string path)
 			{
@@ -342,7 +359,7 @@ namespace Tgstation.Server.Host.Components.Byond
 
 				var bytes = await ioManager.ReadAllBytes(versionFile, cancellationToken);
 				var text = Encoding.UTF8.GetString(bytes);
-				if (!Version.TryParse(text, out var version))
+				if (!ByondVersion.TryParse(text, out var version))
 				{
 					logger.LogWarning("Cleaning path with unparsable version file: {versionPath}", ioManager.ResolvePath(path));
 					await ioManager.DeleteDirectory(path, cancellationToken); // cleanup
@@ -383,10 +400,10 @@ namespace Tgstation.Server.Host.Components.Byond
 			{
 				var activeVersionString = Encoding.UTF8.GetString(activeVersionBytes);
 
-				Version activeVersion;
+				ByondVersion activeVersion;
 				bool hasRequestedActiveVersion;
 				lock (installedVersions)
-					hasRequestedActiveVersion = Version.TryParse(activeVersionString, out activeVersion)
+					hasRequestedActiveVersion = ByondVersion.TryParse(activeVersionString, out activeVersion)
 						&& installedVersions.ContainsKey(activeVersion);
 
 				if (hasRequestedActiveVersion)
@@ -403,46 +420,47 @@ namespace Tgstation.Server.Host.Components.Byond
 		public Task StopAsync(CancellationToken cancellationToken) => Task.CompletedTask;
 
 		/// <summary>
-		/// Ensures a BYOND <paramref name="version"/> is installed if it isn't already.
+		/// Ensures a BYOND <paramref name="byondVersion"/> is installed if it isn't already.
 		/// </summary>
 		/// <param name="progressReporter">The optional <see cref="JobProgressReporter"/> for the operation.</param>
-		/// <param name="version">The BYOND <see cref="Version"/> to install.</param>
+		/// <param name="byondVersion">The <see cref="ByondVersion"/> to install.</param>
 		/// <param name="customVersionStream">Custom zip file <see cref="Stream"/> to use. Will cause a <see cref="Version.Build"/> number to be added.</param>
 		/// <param name="neededForLock">If this BYOND version is required as part of a locking operation.</param>
-		/// <param name="allowInstallation">If an installation should be performed if the <paramref name="version"/> is not installed. If <see langword="false"/> and an installation is required an <see cref="InvalidOperationException"/> will be thrown.</param>
+		/// <param name="allowInstallation">If an installation should be performed if the <paramref name="byondVersion"/> is not installed. If <see langword="false"/> and an installation is required an <see cref="InvalidOperationException"/> will be thrown.</param>
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
-		/// <returns>A <see cref="ValueTask{TResult}"/> resulting in the <see cref="ByondExecutableLock"/>.</returns>
-		async ValueTask<ByondExecutableLock> AssertAndLockVersion(
+		/// <returns>A <see cref="ValueTask{TResult}"/> resulting in the <see cref="EngineExecutableLock"/>.</returns>
+		async ValueTask<EngineExecutableLock> AssertAndLockVersion(
 			JobProgressReporter progressReporter,
-			Version version,
+			ByondVersion byondVersion,
 			Stream customVersionStream,
 			bool neededForLock,
 			bool allowInstallation,
 			CancellationToken cancellationToken)
 		{
 			var ourTcs = new TaskCompletionSource();
-			ByondInstallation installation;
-			ByondExecutableLock installLock;
+			IEngineInstallation installation;
+			EngineExecutableLock installLock;
 			bool installedOrInstalling;
+			var byondEngine = byondVersion.Engine.Value == EngineType.Byond;
 			lock (installedVersions)
 			{
-				if (customVersionStream != null)
+				if (customVersionStream != null && byondEngine)
 				{
 					var customInstallationNumber = 1;
 					do
 					{
-						version = new Version(version.Major, version.Minor, customInstallationNumber++);
+						byondVersion.Version = new Version(byondVersion.Version.Major, byondVersion.Version.Minor, customInstallationNumber++);
 					}
-					while (installedVersions.ContainsKey(version));
+					while (installedVersions.ContainsKey(byondVersion));
 				}
 
-				installedOrInstalling = installedVersions.TryGetValue(version, out var installationContainer);
+				installedOrInstalling = installedVersions.TryGetValue(byondVersion, out var installationContainer);
 				if (!installedOrInstalling)
 				{
 					if (!allowInstallation)
-						throw new InvalidOperationException($"BYOND version {version} not installed!");
+						throw new InvalidOperationException($"BYOND version {byondVersion} not installed!");
 
-					installationContainer = AddInstallationContainer(version, ourTcs.Task);
+					installationContainer = AddInstallationContainer(byondVersion, ourTcs.Task);
 				}
 
 				installation = installationContainer.Instance;
@@ -457,7 +475,7 @@ namespace Tgstation.Server.Host.Components.Byond
 						progressReporter.StageName = "Waiting for existing installation job...";
 
 					if (neededForLock && !installation.InstallationTask.IsCompleted)
-						logger.LogWarning("The required BYOND version ({version}) is not readily available! We will have to wait for it to install.", version);
+						logger.LogWarning("The required BYOND version ({version}) is not readily available! We will have to wait for it to install.", byondVersion);
 
 					await installation.InstallationTask.WaitAsync(cancellationToken);
 					return installLock;
@@ -467,24 +485,24 @@ namespace Tgstation.Server.Host.Components.Byond
 				try
 				{
 					if (customVersionStream != null)
-						logger.LogInformation("Installing custom BYOND version as {version}...", version);
+						logger.LogInformation("Installing custom BYOND version as {version}...", byondVersion);
 					else if (neededForLock)
 					{
-						if (version.Build > 0)
+						if (byondEngine && byondVersion.Version.Build > 0)
 							throw new JobException(ErrorCode.ByondNonExistentCustomVersion);
 
-						logger.LogWarning("The required BYOND version ({version}) is not readily available! We will have to install it.", version);
+						logger.LogWarning("The required BYOND version ({version}) is not readily available! We will have to install it.", byondVersion);
 					}
 					else
-						logger.LogDebug("Requested BYOND version {version} not currently installed. Doing so now...", version);
+						logger.LogDebug("Requested BYOND version {version} not currently installed. Doing so now...", byondVersion);
 
 					if (progressReporter != null)
 						progressReporter.StageName = "Running event";
 
-					var versionString = version.ToString();
+					var versionString = byondVersion.ToString();
 					await eventConsumer.HandleEvent(EventType.ByondInstallStart, new List<string> { versionString }, false, cancellationToken);
 
-					await InstallVersionFiles(progressReporter, version, customVersionStream, cancellationToken);
+					await InstallVersionFiles(progressReporter, byondVersion, customVersionStream, cancellationToken);
 
 					ourTcs.SetResult();
 				}
@@ -494,7 +512,7 @@ namespace Tgstation.Server.Host.Components.Byond
 						await eventConsumer.HandleEvent(EventType.ByondInstallFail, new List<string> { ex.Message }, false, cancellationToken);
 
 					lock (installedVersions)
-						installedVersions.Remove(version);
+						installedVersions.Remove(byondVersion);
 
 					ourTcs.SetException(ex);
 					throw;
@@ -513,11 +531,11 @@ namespace Tgstation.Server.Host.Components.Byond
 		/// Installs the files for a given BYOND <paramref name="version"/>.
 		/// </summary>
 		/// <param name="progressReporter">The optional <see cref="JobProgressReporter"/> for the operation.</param>
-		/// <param name="version">The BYOND <see cref="Version"/> being installed with the <see cref="Version.Build"/> number set if appropriate.</param>
+		/// <param name="version">The <see cref="ByondVersion"/> being installed with the <see cref="Version.Build"/> number set if appropriate.</param>
 		/// <param name="customVersionStream">Custom zip file <see cref="Stream"/> to use. Will cause a <see cref="Version.Build"/> number to be added.</param>
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
 		/// <returns>A <see cref="ValueTask"/> representing the running operation.</returns>
-		async ValueTask InstallVersionFiles(JobProgressReporter progressReporter, Version version, Stream customVersionStream, CancellationToken cancellationToken)
+		async ValueTask InstallVersionFiles(JobProgressReporter progressReporter, ByondVersion version, Stream customVersionStream, CancellationToken cancellationToken)
 		{
 			var installFullPath = ioManager.ResolvePath(version.ToString());
 			async ValueTask DirectoryCleanup()
@@ -585,32 +603,46 @@ namespace Tgstation.Server.Host.Components.Byond
 		}
 
 		/// <summary>
-		/// Create and add a new <see cref="ByondInstallation"/> to <see cref="installedVersions"/>.
+		/// Create and add a new <see cref="IEngineInstallation"/> to <see cref="installedVersions"/>.
 		/// </summary>
 		/// <param name="version">The <see cref="Version"/> being added.</param>
 		/// <param name="installationTask">The <see cref="ValueTask"/> representing the installation process.</param>
-		/// <returns>The new <see cref="ReferenceCountingContainer{TWrapped, TReference}"/> containing the new <see cref="ByondInstallation"/>.</returns>
-		ReferenceCountingContainer<ByondInstallation, ByondExecutableLock> AddInstallationContainer(Version version, Task installationTask)
+		/// <returns>The new <see cref="ReferenceCountingContainer{TWrapped, TReference}"/> containing the new <see cref="IEngineInstallation"/>.</returns>
+		ReferenceCountingContainer<IEngineInstallation, EngineExecutableLock> AddInstallationContainer(ByondVersion version, Task installationTask)
 		{
 			var binPathForVersion = ioManager.ConcatPath(version.ToString(), BinPath);
-			var installation = new ByondInstallation(
-				installationTask,
-				version,
-				ioManager.ResolvePath(
-					ioManager.ConcatPath(
-						binPathForVersion,
-						byondInstaller.GetDreamDaemonName(
-							version,
-							out var supportsCli,
-							out var supportsMapThreads))),
-				ioManager.ResolvePath(
-					ioManager.ConcatPath(
-						binPathForVersion,
-						byondInstaller.DreamMakerName)),
-				supportsCli,
-				supportsMapThreads);
+			IEngineInstallation installation;
 
-			var installationContainer = new ReferenceCountingContainer<ByondInstallation, ByondExecutableLock>(installation);
+			switch (version.Engine.Value)
+			{
+				case EngineType.Byond:
+					installation = new ByondInstallation(
+						installationTask,
+						version,
+						ioManager.ResolvePath(
+							ioManager.ConcatPath(
+								binPathForVersion,
+								byondInstaller.GetDreamDaemonName(
+									version,
+									out var supportsCli,
+									out var supportsMapThreads))),
+						ioManager.ResolvePath(
+							ioManager.ConcatPath(
+								binPathForVersion,
+								byondInstaller.CompilerName)),
+						supportsCli,
+						supportsMapThreads);
+					break;
+				case EngineType.OpenDream:
+					installation = new OpenDreamInstallation(
+						installationTask,
+						version);
+					break;
+				default:
+					throw new InvalidOperationException($"Invalid EngineType: {version.Engine.Value}");
+			}
+
+			var installationContainer = new ReferenceCountingContainer<IEngineInstallation, EngineExecutableLock>(installation);
 
 			lock (installedVersions)
 				installedVersions.Add(version, installationContainer);
@@ -626,7 +658,7 @@ namespace Tgstation.Server.Host.Components.Byond
 		/// <returns>A <see cref="ValueTask"/> representing the running operation.</returns>
 		async ValueTask TrustDmbPath(string fullDmbPath, CancellationToken cancellationToken)
 		{
-			var byondDir = byondInstaller.PathToUserByondFolder;
+			var byondDir = byondInstaller.PathToUserFolder;
 			if (String.IsNullOrWhiteSpace(byondDir))
 			{
 				logger.LogTrace("No relevant user BYOND directory to install a \"{fileName}\" in", TrustedDmbFileName);

src/Tgstation.Server.Host/Components/Byond/EngineExecutableLock.cs

@@ -0,0 +1,49 @@
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+using Tgstation.Server.Api.Models.Internal;
+using Tgstation.Server.Host.Components.Deployment;
+using Tgstation.Server.Host.Utils;
+
+namespace Tgstation.Server.Host.Components.Byond
+{
+	/// <inheritdoc cref="IEngineExecutableLock" />
+	sealed class EngineExecutableLock : ReferenceCounter<IEngineInstallation>, IEngineExecutableLock
+	{
+		/// <inheritdoc />
+		public ByondVersion Version => Instance.Version;
+
+		/// <inheritdoc />
+		public string ServerExePath => Instance.ServerExePath;
+
+		/// <inheritdoc />
+		public string CompilerExePath => Instance.CompilerExePath;
+
+		/// <inheritdoc />
+		public bool HasStandardOutput => Instance.HasStandardOutput;
+
+		/// <inheritdoc />
+		public bool PromptsForNetworkAccess => Instance.PromptsForNetworkAccess;
+
+		/// <inheritdoc />
+		public Task InstallationTask => Instance.InstallationTask;
+
+		/// <inheritdoc />
+		public void DoNotDeleteThisSession() => DangerousDropReference();
+
+		/// <inheritdoc />
+		public string FormatServerArguments(
+			IDmbProvider dmbProvider,
+			IReadOnlyDictionary<string, string> parameters,
+			DreamDaemonLaunchParameters launchParameters,
+			string logFilePath)
+			=> Instance.FormatServerArguments(
+				dmbProvider,
+				parameters,
+				launchParameters,
+				logFilePath);
+
+		/// <inheritdoc />
+		public string FormatCompilerArguments(string dmePath) => Instance.FormatCompilerArguments(dmePath);
+	}
+}

src/Tgstation.Server.Host/Components/Byond/IByondInstallation.cs

@@ -1,35 +0,0 @@
-using System;
-
-namespace Tgstation.Server.Host.Components.Byond
-{
-	/// <summary>
-	/// Represents a BYOND installation.
-	/// </summary>
-	public interface IByondInstallation
-	{
-		/// <summary>
-		/// The <see cref="global::System.Version"/> of the <see cref="IByondInstallation"/>.
-		/// </summary>
-		Version Version { get; }
-
-		/// <summary>
-		/// The full path to the DreamDaemon executable.
-		/// </summary>
-		string DreamDaemonPath { get; }
-
-		/// <summary>
-		/// The full path to the dm/DreamMaker executable.
-		/// </summary>
-		string DreamMakerPath { get; }
-
-		/// <summary>
-		/// If <see cref="DreamDaemonPath"/> supports being run as a command-line application.
-		/// </summary>
-		bool SupportsCli { get; }
-
-		/// <summary>
-		/// If <see cref="DreamDaemonPath"/> supports the -map-threads parameter.
-		/// </summary>
-		bool SupportsMapThreads { get; }
-	}
-}

src/Tgstation.Server.Host/Components/Byond/IByondInstaller.cs

@@ -1,8 +1,9 @@
-using System;
-using System.IO;
+using System.IO;
 using System.Threading;
 using System.Threading.Tasks;
 
+using Tgstation.Server.Api.Models.Internal;
+
 namespace Tgstation.Server.Host.Components.Byond
 {
 	/// <summary>
@@ -11,52 +12,52 @@ namespace Tgstation.Server.Host.Components.Byond
 	interface IByondInstaller
 	{
 		/// <summary>
-		/// Get the file name of the DreamMaker executable.
+		/// Get the file name of the compiler executable.
 		/// </summary>
-		string DreamMakerName { get; }
+		string CompilerName { get; }
 
 		/// <summary>
-		/// The path to the BYOND folder for the user.
+		/// The path to the folder for the user's data.
 		/// </summary>
-		string PathToUserByondFolder { get; }
+		string PathToUserFolder { get; }
 
 		/// <summary>
 		/// Get the file name of the DreamDaemon executable.
 		/// </summary>
-		/// <param name="version">The <see cref="Version"/> of BYOND to select the executable name for.</param>
+		/// <param name="version">The <see cref="ByondVersion"/> of BYOND to select the executable name for.</param>
 		/// <param name="supportsCli">Whether or not the returned path supports being run as a command-line application.</param>
 		/// <param name="supportsMapThreads">Whether or not the returned path supports the '-map-threads' parameter.</param>
 		/// <returns>The file name of the DreamDaemon executable.</returns>
-		string GetDreamDaemonName(Version version, out bool supportsCli, out bool supportsMapThreads);
+		string GetDreamDaemonName(ByondVersion version, out bool supportsCli, out bool supportsMapThreads);
 
 		/// <summary>
 		/// Download a given BYOND <paramref name="version"/>.
 		/// </summary>
-		/// <param name="version">The <see cref="Version"/> of BYOND to download.</param>
+		/// <param name="version">The <see cref="ByondVersion"/> of BYOND to download.</param>
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
 		/// <returns>A <see cref="ValueTask{TResult}"/> resulting in a <see cref="MemoryStream"/> of the zipfile.</returns>
-		ValueTask<MemoryStream> DownloadVersion(Version version, CancellationToken cancellationToken);
+		ValueTask<MemoryStream> DownloadVersion(ByondVersion version, CancellationToken cancellationToken);
 
 		/// <summary>
 		/// Does actions necessary to get an extracted BYOND installation working.
 		/// </summary>
-		/// <param name="version">The <see cref="Version"/> of BYOND being installed.</param>
+		/// <param name="version">The <see cref="ByondVersion"/> being installed.</param>
 		/// <param name="path">The path to the BYOND installation.</param>
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
 		/// <returns>A <see cref="ValueTask"/> representing the running operation.</returns>
-		ValueTask InstallByond(Version version, string path, CancellationToken cancellationToken);
+		ValueTask InstallByond(ByondVersion version, string path, CancellationToken cancellationToken);
 
 		/// <summary>
 		/// Does actions necessary to get upgrade a BYOND version installed by a previous version of TGS.
 		/// </summary>
-		/// <param name="version">The <see cref="Version"/> of BYOND being installed.</param>
+		/// <param name="version">The <see cref="ByondVersion"/> being installed.</param>
 		/// <param name="path">The path to the BYOND installation.</param>
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
 		/// <returns>A <see cref="ValueTask"/> representing the running operation.</returns>
-		ValueTask UpgradeInstallation(Version version, string path, CancellationToken cancellationToken);
+		ValueTask UpgradeInstallation(ByondVersion version, string path, CancellationToken cancellationToken);
 
 		/// <summary>
-		/// Attempts to cleans the BYOND cache folder for the system.
+		/// Attempts to cleans the engine's cache folder for the system.
 		/// </summary>
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
 		/// <returns>A <see cref="Task"/> representing the running operation.</returns>

src/Tgstation.Server.Host/Components/Byond/IByondManager.cs

@@ -4,6 +4,8 @@ using System.IO;
 using System.Threading;
 using System.Threading.Tasks;
 
+using Tgstation.Server.Api.Models;
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Host.Jobs;
 
 namespace Tgstation.Server.Host.Components.Byond
@@ -11,48 +13,62 @@ namespace Tgstation.Server.Host.Components.Byond
 	/// <summary>
 	/// For managing the BYOND installation.
 	/// </summary>
-	/// <remarks>When passing in <see cref="Version"/>s, ensure they are BYOND format versions unless referring to a custom version. This means <see cref="Version.Build"/> should NEVER be 0.</remarks>
+	/// <remarks>When passing in <see cref="ByondVersion.Version"/>s for <see cref="EngineType.Byond"/>, ensure they are BYOND format versions unless referring to a custom version. This means <see cref="Version.Build"/> should NEVER be 0.</remarks>
 	public interface IByondManager : IComponentService, IDisposable
 	{
 		/// <summary>
-		/// The currently active BYOND version.
+		/// The currently active <see cref="ByondVersion"/>.
 		/// </summary>
-		Version ActiveVersion { get; }
+		ByondVersion ActiveVersion { get; }
 
 		/// <summary>
-		/// The installed BYOND versions.
+		/// The installed <see cref="ByondVersion"/>s.
 		/// </summary>
-		IReadOnlyList<Version> InstalledVersions { get; }
+		IReadOnlyList<ByondVersion> InstalledVersions { get; }
 
 		/// <summary>
-		/// Change the active BYOND version.
+		/// Ensure that the given <paramref name="source"/> is registered for the given <paramref name="engine"/>.
+		/// </summary>
+		/// <param name="source">The <see cref="Uri"/> source of the <paramref name="engine"/>.</param>
+		/// <param name="engine">The <see cref="EngineType"/>.</param>
+		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
+		/// <returns>A <see cref="ValueTask"/> representing the running operation.</returns>
+		ValueTask EnsureEngineSource(Uri source, EngineType engine, CancellationToken cancellationToken);
+
+		/// <summary>
+		/// Change the active <see cref="ByondVersion"/>.
 		/// </summary>
 		/// <param name="progressReporter">The optional <see cref="JobProgressReporter"/> for the operation.</param>
-		/// <param name="version">The new <see cref="Version"/>.</param>
+		/// <param name="version">The new <see cref="ByondVersion"/>.</param>
 		/// <param name="customVersionStream">Optional <see cref="Stream"/> of a custom BYOND version zip file.</param>
 		/// <param name="allowInstallation">If an installation should be performed if the <paramref name="version"/> is not installed. If <see langword="false"/> and an installation is required an <see cref="InvalidOperationException"/> will be thrown.</param>
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
 		/// <returns>A <see cref="ValueTask"/> representing the running operation.</returns>
-		ValueTask ChangeVersion(JobProgressReporter progressReporter, Version version, Stream customVersionStream, bool allowInstallation, CancellationToken cancellationToken);
+		ValueTask ChangeVersion(
+			JobProgressReporter progressReporter,
+			ByondVersion version,
+			Stream customVersionStream,
+			bool allowInstallation,
+			CancellationToken cancellationToken);
 
 		/// <summary>
-		/// Deletes a given BYOND version from the disk.
+		/// Deletes a given <paramref name="version"/> from the disk.
 		/// </summary>
 		/// <param name="progressReporter">The <see cref="JobProgressReporter"/> for the operation.</param>
-		/// <param name="version">The <see cref="Version"/> to delete.</param>
+		/// <param name="version">The <see cref="ByondVersion"/> to delete.</param>
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
-		/// <returns>A <see cref="ValueTask"/> representing the running operation.</returns>
-		ValueTask DeleteVersion(JobProgressReporter progressReporter, Version version, CancellationToken cancellationToken);
+		/// <returns>A <see cref="Task"/> representing the running operation.</returns>
+		ValueTask DeleteVersion(JobProgressReporter progressReporter, ByondVersion version, CancellationToken cancellationToken);
 
 		/// <summary>
-		/// Lock the current installation's location and return a <see cref="IByondExecutableLock"/>.
+		/// Lock the current installation's location and return a <see cref="IEngineExecutableLock"/>.
 		/// </summary>
-		/// <param name="requiredVersion">The BYOND <see cref="Version"/> required.</param>
+		/// <param name="requiredVersion">The <see cref="ByondVersion"/> required.</param>
 		/// <param name="trustDmbFullPath">The optional full path to .dmb to trust while using the executables.</param>
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
-		/// <returns>A <see cref="ValueTask{TResult}"/> resulting in the requested <see cref="IByondExecutableLock"/>.</returns>
-		ValueTask<IByondExecutableLock> UseExecutables(
-			Version requiredVersion,
+		/// <returns>A <see cref="ValueTask{TResult}"/> resulting in the requested <see cref="IEngineExecutableLock"/>.</returns>
+		ValueTask<IEngineExecutableLock> UseExecutables(
+			ByondVersion requiredVersion,
 			string trustDmbFullPath,
 			CancellationToken cancellationToken);
 	}

src/Tgstation.Server.Host/Components/Byond/IEngineExecutableLock.cs

@@ -5,7 +5,7 @@ namespace Tgstation.Server.Host.Components.Byond
 	/// <summary>
 	/// Represents usage of the two primary BYOND server executables.
 	/// </summary>
-	public interface IByondExecutableLock : IByondInstallation, IDisposable
+	public interface IEngineExecutableLock : IEngineInstallation, IDisposable
 	{
 		/// <summary>
 		/// Call if, during a detach, this version should not be deleted.

src/Tgstation.Server.Host/Components/Byond/IEngineInstallation.cs

@@ -0,0 +1,65 @@
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+using Tgstation.Server.Api.Models.Internal;
+using Tgstation.Server.Host.Components.Deployment;
+
+namespace Tgstation.Server.Host.Components.Byond
+{
+	/// <summary>
+	/// Represents a BYOND installation.
+	/// </summary>
+	public interface IEngineInstallation
+	{
+		/// <summary>
+		/// The <see cref="ByondVersion"/> of the <see cref="IEngineInstallation"/>.
+		/// </summary>
+		ByondVersion Version { get; }
+
+		/// <summary>
+		/// The full path to the game server executable.
+		/// </summary>
+		string ServerExePath { get; }
+
+		/// <summary>
+		/// The full path to the dm/DreamMaker executable.
+		/// </summary>
+		string CompilerExePath { get; }
+
+		/// <summary>
+		/// If <see cref="ServerExePath"/> supports being run as a command-line application and outputs log information to be captured.
+		/// </summary>
+		bool HasStandardOutput { get; }
+
+		/// <summary>
+		/// If <see cref="ServerExePath"/> may create network prompts.
+		/// </summary>
+		bool PromptsForNetworkAccess { get; }
+
+		/// <summary>
+		/// The <see cref="Task"/> that completes when the BYOND version finished installing.
+		/// </summary>
+		Task InstallationTask { get; }
+
+		/// <summary>
+		/// Return the command line arguments for launching with given <paramref name="launchParameters"/>.
+		/// </summary>
+		/// <param name="dmbProvider">The <see cref="IDmbProvider"/>.</param>
+		/// <param name="parameters">The map of parameter <see cref="string"/>s as a <see cref="IReadOnlyDictionary{TKey, TValue}"/>. Should NOT include the <see cref="DreamDaemonLaunchParameters.AdditionalParameters"/> of <paramref name="launchParameters"/>.</param>
+		/// <param name="launchParameters">The <see cref="DreamDaemonLaunchParameters"/>.</param>
+		/// <param name="logFilePath">The path to the log file, if any.</param>
+		/// <returns>The formatted arguments <see cref="string"/>.</returns>
+		string FormatServerArguments(
+			IDmbProvider dmbProvider,
+			IReadOnlyDictionary<string, string> parameters,
+			DreamDaemonLaunchParameters launchParameters,
+			string logFilePath);
+
+		/// <summary>
+		/// Return the command line arguments for compiling a given <paramref name="dmePath"/> if compilation is necessary.
+		/// </summary>
+		/// <param name="dmePath">The full path to the .dme to compile.</param>
+		/// <returns>An arguments <see cref="string"/> if compilation is required, <see langword="null"/> otherwise.</returns>
+		string FormatCompilerArguments(string dmePath);
+	}
+}

src/Tgstation.Server.Host/Components/Byond/OpenDreamInstallation.cs

@@ -0,0 +1,67 @@
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+using Tgstation.Server.Api.Models;
+using Tgstation.Server.Api.Models.Internal;
+using Tgstation.Server.Host.Components.Deployment;
+
+namespace Tgstation.Server.Host.Components.Byond
+{
+	/// <summary>
+	/// Implementation of <see cref="IEngineInstallation"/> for <see cref="EngineType.OpenDream"/>.
+	/// </summary>
+	sealed class OpenDreamInstallation : IEngineInstallation
+	{
+		/// <inheritdoc />
+		public ByondVersion Version { get; }
+
+		/// <inheritdoc />
+		public string ServerExePath { get; }
+
+		/// <inheritdoc />
+		public string CompilerExePath { get; }
+
+		/// <inheritdoc />
+		public bool PromptsForNetworkAccess => false;
+
+		/// <inheritdoc />
+		public bool HasStandardOutput => true;
+
+		/// <inheritdoc />
+		public Task InstallationTask { get; }
+
+		/// <summary>
+		/// Initializes a new instance of the <see cref="OpenDreamInstallation"/> class.
+		/// </summary>
+		/// <param name="installationTask">The value of <see cref="InstallationTask"/>.</param>
+		/// <param name="version">The value of <see cref="Version"/>.</param>
+		public OpenDreamInstallation(
+			Task installationTask,
+			ByondVersion version)
+		{
+			InstallationTask = installationTask ?? throw new ArgumentNullException(nameof(installationTask));
+			ArgumentNullException.ThrowIfNull(version);
+
+			if (version.Engine.Value != EngineType.OpenDream)
+				throw new ArgumentException($"Invalid EngineType: {version.Engine.Value}", nameof(version));
+
+			Version = version ?? throw new ArgumentNullException(nameof(version));
+
+			throw new NotImplementedException();
+		}
+
+		/// <inheritdoc />
+		public string FormatServerArguments(IDmbProvider dmbProvider, IReadOnlyDictionary<string, string> parameters, DreamDaemonLaunchParameters launchParameters, string logFilePath)
+		{
+			throw new NotImplementedException();
+		}
+
+		/// <inheritdoc />
+		public string FormatCompilerArguments(string dmePath)
+		{
+			ArgumentNullException.ThrowIfNull(dmePath);
+			return null;
+		}
+	}
+}

src/Tgstation.Server.Host/Components/Byond/PosixByondInstaller.cs

@@ -6,6 +6,7 @@ using System.Threading.Tasks;
 
 using Microsoft.Extensions.Logging;
 
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Common.Extensions;
 using Tgstation.Server.Host.IO;
 
@@ -32,10 +33,10 @@ namespace Tgstation.Server.Host.Components.Byond
 		const string ShellScriptExtension = ".sh";
 
 		/// <inheritdoc />
-		public override string DreamMakerName => DreamMakerExecutableName + ShellScriptExtension;
+		public override string CompilerName => DreamMakerExecutableName + ShellScriptExtension;
 
 		/// <inheritdoc />
-		public override string PathToUserByondFolder { get; }
+		public override string PathToUserFolder { get; }
 
 		/// <inheritdoc />
 		protected override string ByondRevisionsUrlTemplate => "https://www.byond.com/download/build/{0}/{0}.{1}_byond_linux.zip";
@@ -61,7 +62,7 @@ namespace Tgstation.Server.Host.Components.Byond
 		{
 			this.postWriteHandler = postWriteHandler ?? throw new ArgumentNullException(nameof(postWriteHandler));
 
-			PathToUserByondFolder = IOManager.ResolvePath(
+			PathToUserFolder = IOManager.ResolvePath(
 				IOManager.ConcatPath(
 					Environment.GetFolderPath(
 						Environment.SpecialFolder.UserProfile),
@@ -69,17 +70,17 @@ namespace Tgstation.Server.Host.Components.Byond
 		}
 
 		/// <inheritdoc />
-		public override string GetDreamDaemonName(Version version, out bool supportsCli, out bool supportsMapThreads)
+		public override string GetDreamDaemonName(ByondVersion version, out bool supportsCli, out bool supportsMapThreads)
 		{
 			ArgumentNullException.ThrowIfNull(version);
 
 			supportsCli = true;
-			supportsMapThreads = version >= MapThreadsVersion;
+			supportsMapThreads = version.Version >= MapThreadsVersion;
 			return DreamDaemonExecutableName + ShellScriptExtension;
 		}
 
 		/// <inheritdoc />
-		public override ValueTask InstallByond(Version version, string path, CancellationToken cancellationToken)
+		public override ValueTask InstallByond(ByondVersion version, string path, CancellationToken cancellationToken)
 		{
 			ArgumentNullException.ThrowIfNull(version);
 			ArgumentNullException.ThrowIfNull(path);
@@ -105,7 +106,7 @@ namespace Tgstation.Server.Host.Components.Byond
 				dreamDaemonScript);
 
 			var dmTask = WriteAndMakeExecutable(
-				IOManager.ConcatPath(basePath, DreamMakerName),
+				IOManager.ConcatPath(basePath, CompilerName),
 				dreamMakerScript);
 
 			var task = ValueTaskExtensions.WhenAll(
@@ -119,7 +120,7 @@ namespace Tgstation.Server.Host.Components.Byond
 		}
 
 		/// <inheritdoc />
-		public override ValueTask UpgradeInstallation(Version version, string path, CancellationToken cancellationToken)
+		public override ValueTask UpgradeInstallation(ByondVersion version, string path, CancellationToken cancellationToken)
 		{
 			ArgumentNullException.ThrowIfNull(version);
 			ArgumentNullException.ThrowIfNull(path);

src/Tgstation.Server.Host/Components/Byond/WindowsByondInstaller.cs

@@ -8,6 +8,7 @@ using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
 
 using Tgstation.Server.Api.Models;
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Common.Extensions;
 using Tgstation.Server.Host.Configuration;
 using Tgstation.Server.Host.IO;
@@ -53,10 +54,10 @@ namespace Tgstation.Server.Host.Components.Byond
 		public static Version DDExeVersion => new (515, 1598);
 
 		/// <inheritdoc />
-		public override string DreamMakerName => "dm.exe";
+		public override string CompilerName => "dm.exe";
 
 		/// <inheritdoc />
-		public override string PathToUserByondFolder { get; }
+		public override string PathToUserFolder { get; }
 
 		/// <inheritdoc />
 		protected override string ByondRevisionsUrlTemplate => "https://www.byond.com/download/build/{0}/{0}.{1}_byond.zip";
@@ -102,9 +103,9 @@ namespace Tgstation.Server.Host.Components.Byond
 
 			var documentsDirectory = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
 			if (String.IsNullOrWhiteSpace(documentsDirectory))
-				PathToUserByondFolder = null; // happens with the service account
+				PathToUserFolder = null; // happens with the service account
 			else
-				PathToUserByondFolder = IOManager.ResolvePath(IOManager.ConcatPath(documentsDirectory, "BYOND"));
+				PathToUserFolder = IOManager.ResolvePath(IOManager.ConcatPath(documentsDirectory, "BYOND"));
 
 			semaphore = new SemaphoreSlim(1);
 			installedDirectX = false;
@@ -114,17 +115,17 @@ namespace Tgstation.Server.Host.Components.Byond
 		public void Dispose() => semaphore.Dispose();
 
 		/// <inheritdoc />
-		public override string GetDreamDaemonName(Version version, out bool supportsCli, out bool supportsMapThreads)
+		public override string GetDreamDaemonName(ByondVersion version, out bool supportsCli, out bool supportsMapThreads)
 		{
 			ArgumentNullException.ThrowIfNull(version);
 
-			supportsCli = version >= DDExeVersion;
-			supportsMapThreads = version >= MapThreadsVersion;
+			supportsCli = version.Version >= DDExeVersion;
+			supportsMapThreads = version.Version >= MapThreadsVersion;
 			return supportsCli ? "dd.exe" : "dreamdaemon.exe";
 		}
 
 		/// <inheritdoc />
-		public override ValueTask InstallByond(Version version, string path, CancellationToken cancellationToken)
+		public override ValueTask InstallByond(ByondVersion version, string path, CancellationToken cancellationToken)
 		{
 			var tasks = new List<ValueTask>(3)
 			{
@@ -139,7 +140,7 @@ namespace Tgstation.Server.Host.Components.Byond
 		}
 
 		/// <inheritdoc />
-		public override async ValueTask UpgradeInstallation(Version version, string path, CancellationToken cancellationToken)
+		public override async ValueTask UpgradeInstallation(ByondVersion version, string path, CancellationToken cancellationToken)
 		{
 			ArgumentNullException.ThrowIfNull(version);
 			ArgumentNullException.ThrowIfNull(path);
@@ -147,7 +148,7 @@ namespace Tgstation.Server.Host.Components.Byond
 			if (generalConfiguration.SkipAddingByondFirewallException)
 				return;
 
-			if (version < DDExeVersion)
+			if (version.Version < DDExeVersion)
 				return;
 
 			if (await IOManager.FileExists(IOManager.ConcatPath(path, TgsFirewalledDDFile), cancellationToken))
@@ -227,7 +228,7 @@ namespace Tgstation.Server.Host.Components.Byond
 		/// <param name="path">The path to the BYOND installation.</param>
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
 		/// <returns>A <see cref="ValueTask"/> representing the running operation.</returns>
-		async ValueTask AddDreamDaemonToFirewall(Version version, string path, CancellationToken cancellationToken)
+		async ValueTask AddDreamDaemonToFirewall(ByondVersion version, string path, CancellationToken cancellationToken)
 		{
 			var dreamDaemonName = GetDreamDaemonName(version, out var usesDDExe, out var _);
 

src/Tgstation.Server.Host/Components/Chat/ChatManager.cs

@@ -359,7 +359,7 @@ namespace Tgstation.Server.Host.Components.Chat
 		/// <inheritdoc />
 		public Func<string, string, Action<bool>> QueueDeploymentMessage(
 			Models.RevisionInformation revisionInformation,
-			Version byondVersion,
+			ByondVersion byondVersion,
 			DateTimeOffset? estimatedCompletionTime,
 			string gitHubOwner,
 			string gitHubRepo,

src/Tgstation.Server.Host/Components/Chat/Commands/ByondCommand.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Globalization;
 using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
@@ -49,20 +48,45 @@ namespace Tgstation.Server.Host.Components.Chat.Commands
 		/// <inheritdoc />
 		public ValueTask<MessageContent> Invoke(string arguments, ChatUser user, CancellationToken cancellationToken)
 		{
-			if (arguments.Split(' ').Any(x => x.ToUpperInvariant() == "--ACTIVE"))
-				return ValueTask.FromResult(new MessageContent
-				{
-					Text = byondManager.ActiveVersion == null ? "None!" : String.Format(CultureInfo.InvariantCulture, "{0}.{1}", byondManager.ActiveVersion.Major, byondManager.ActiveVersion.Minor),
-				});
-			if (watchdog.Status == WatchdogStatus.Offline)
-				return ValueTask.FromResult(new MessageContent
-				{
-					Text = "Server offline!",
-				});
-			return ValueTask.FromResult(new MessageContent
+			if (arguments.Split(' ').Any(x => x.Equals("--active", StringComparison.OrdinalIgnoreCase)))
 			{
-				Text = watchdog.ActiveCompileJob?.ByondVersion ?? "None!",
-			});
+				string text;
+				if (byondManager.ActiveVersion == null)
+					text = "None!";
+				else
+					switch (byondManager.ActiveVersion.Engine.Value)
+					{
+						case EngineType.OpenDream:
+							text = $"OpenDream: {byondManager.ActiveVersion.SourceCommittish}";
+							break;
+						case EngineType.Byond:
+							text = $"BYOND {byondManager.ActiveVersion.Version.Major}.{byondManager.ActiveVersion.Version.Minor}";
+							if (byondManager.ActiveVersion.Version.Build != -1)
+								text += " (Custom Build)";
+
+							break;
+						default:
+							throw new InvalidOperationException($"Invalid EngineType: {byondManager.ActiveVersion.Engine.Value}");
+					}
+
+				return ValueTask.FromResult(
+					new MessageContent
+					{
+						Text = text,
+					});
+			}
+
+			if (watchdog.Status == WatchdogStatus.Offline)
+				return ValueTask.FromResult(
+					new MessageContent
+					{
+						Text = "Server offline!",
+					});
+			return ValueTask.FromResult(
+				new MessageContent
+				{
+					Text = watchdog.ActiveCompileJob?.ByondVersion ?? "None!",
+				});
 		}
 	}
 }

src/Tgstation.Server.Host/Components/Chat/IChatManager.cs

@@ -61,7 +61,7 @@ namespace Tgstation.Server.Host.Components.Chat
 		/// Send the message for a deployment to configured deployment channels.
 		/// </summary>
 		/// <param name="revisionInformation">The <see cref="RevisionInformation"/> of the deployment.</param>
-		/// <param name="byondVersion">The BYOND <see cref="Version"/> of the deployment.</param>
+		/// <param name="byondVersion">The <see cref="ByondVersion"/> of the deployment.</param>
 		/// <param name="estimatedCompletionTime">The optional <see cref="DateTimeOffset"/> the deployment is expected to be completed at.</param>
 		/// <param name="gitHubOwner">The repository GitHub owner, if any.</param>
 		/// <param name="gitHubRepo">The repository GitHub name, if any.</param>
@@ -69,7 +69,7 @@ namespace Tgstation.Server.Host.Components.Chat
 		/// <returns>A <see cref="Func{T1, T2, TResult}"/> to call to update the message at the deployment's conclusion. Parameters: Error message if any, DreamMaker output if any. Returns an <see cref="Action"/> to call to mark the deployment as active/inactive. Parameter: If the deployment is being activated or inactivated.</returns>
 		Func<string, string, Action<bool>> QueueDeploymentMessage(
 			Models.RevisionInformation revisionInformation,
-			Version byondVersion,
+			ByondVersion byondVersion,
 			DateTimeOffset? estimatedCompletionTime,
 			string gitHubOwner,
 			string gitHubRepo,

src/Tgstation.Server.Host/Components/Chat/Providers/DiscordProvider.cs

@@ -22,6 +22,7 @@ using Remora.Rest.Results;
 using Remora.Results;
 
 using Tgstation.Server.Api.Models;
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Common.Extensions;
 using Tgstation.Server.Host.Components.Interop;
 using Tgstation.Server.Host.Extensions;
@@ -129,25 +130,35 @@ namespace Tgstation.Server.Host.Components.Chat.Providers
 		/// Create a <see cref="List{T}"/> of <see cref="IEmbedField"/>s for a discord update embed.
 		/// </summary>
 		/// <param name="revisionInformation">The <see cref="RevisionInformation"/> of the deployment.</param>
-		/// <param name="byondVersion">The BYOND <see cref="Version"/> of the deployment.</param>
+		/// <param name="byondVersion">The <see cref="ByondVersion"/> of the deployment.</param>
 		/// <param name="gitHubOwner">The repository GitHub owner, if any.</param>
 		/// <param name="gitHubRepo">The repository GitHub name, if any.</param>
 		/// <param name="localCommitPushed"><see langword="true"/> if the local deployment commit was pushed to the remote repository.</param>
 		/// <returns>A new <see cref="List{T}"/> of <see cref="IEmbedField"/>s to use.</returns>
 		static List<IEmbedField> BuildUpdateEmbedFields(
 			Models.RevisionInformation revisionInformation,
-			Version byondVersion,
+			ByondVersion byondVersion,
 			string gitHubOwner,
 			string gitHubRepo,
 			bool localCommitPushed)
 		{
 			bool gitHub = gitHubOwner != null && gitHubRepo != null;
+			var engineField = byondVersion.Engine.Value switch
+			{
+				EngineType.Byond => new EmbedField(
+					"BYOND Version",
+					$"{byondVersion.Version.Major}.{byondVersion.Version.Minor}{(byondVersion.Version.Build > 0 ? $".{byondVersion.Version.Build}" : String.Empty)}",
+					true),
+				EngineType.OpenDream => new EmbedField(
+					"OpenDream Version",
+					$"[{byondVersion.SourceCommittish[..7]}](https://github.com/OpenDreamProject/OpenDream/commit/{revisionInformation.CommitSha})",
+					true),
+				_ => throw new InvalidOperationException($"Invaild EngineType: {byondVersion.Engine.Value}"),
+			};
+
 			var fields = new List<IEmbedField>
 			{
-				new EmbedField(
-					"BYOND Version",
-					$"{byondVersion.Major}.{byondVersion.Minor}{(byondVersion.Build > 0 ? $".{byondVersion.Build}" : String.Empty)}",
-					true),
+				engineField,
 				new EmbedField(
 					"Local Commit",
 					localCommitPushed && gitHub
@@ -323,7 +334,7 @@ namespace Tgstation.Server.Host.Components.Chat.Providers
 		/// <inheritdoc />
 		public override async ValueTask<Func<string, string, ValueTask<Func<bool, ValueTask>>>> SendUpdateMessage(
 			Models.RevisionInformation revisionInformation,
-			Version byondVersion,
+			ByondVersion byondVersion,
 			DateTimeOffset? estimatedCompletionTime,
 			string gitHubOwner,
 			string gitHubRepo,

src/Tgstation.Server.Host/Components/Chat/Providers/IProvider.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.Threading;
 using System.Threading.Tasks;
 
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Host.Components.Interop;
 using Tgstation.Server.Host.Models;
 
@@ -83,7 +84,7 @@ namespace Tgstation.Server.Host.Components.Chat.Providers
 		/// Send the message for a deployment.
 		/// </summary>
 		/// <param name="revisionInformation">The <see cref="RevisionInformation"/> of the deployment.</param>
-		/// <param name="byondVersion">The BYOND <see cref="Version"/> of the deployment.</param>
+		/// <param name="byondVersion">The <see cref="ByondVersion"/> of the deployment.</param>
 		/// <param name="estimatedCompletionTime">The optional <see cref="DateTimeOffset"/> the deployment is expected to be completed at.</param>
 		/// <param name="gitHubOwner">The repository GitHub owner, if any.</param>
 		/// <param name="gitHubRepo">The repository GitHub name, if any.</param>
@@ -92,8 +93,8 @@ namespace Tgstation.Server.Host.Components.Chat.Providers
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
 		/// <returns>A <see cref="ValueTask{TResult}"/> resulting in a <see cref="Func{T1, T2, TResult}"/> to call to update the message at the deployment's conclusion. Parameters: Error message if any, DreamMaker output if any. Returns another callback which should be called to mark the deployment as active.</returns>
 		ValueTask<Func<string, string, ValueTask<Func<bool, ValueTask>>>> SendUpdateMessage(
-			RevisionInformation revisionInformation,
-			Version byondVersion,
+			Models.RevisionInformation revisionInformation,
+			ByondVersion byondVersion,
 			DateTimeOffset? estimatedCompletionTime,
 			string gitHubOwner,
 			string gitHubRepo,

src/Tgstation.Server.Host/Components/Chat/Providers/IrcProvider.cs

@@ -12,6 +12,7 @@ using Microsoft.Extensions.Logging;
 using Newtonsoft.Json;
 
 using Tgstation.Server.Api.Models;
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Host.Components.Interop;
 using Tgstation.Server.Host.Extensions;
 using Tgstation.Server.Host.IO;
@@ -220,7 +221,7 @@ namespace Tgstation.Server.Host.Components.Chat.Providers
 		/// <inheritdoc />
 		public override async ValueTask<Func<string, string, ValueTask<Func<bool, ValueTask>>>> SendUpdateMessage(
 			Models.RevisionInformation revisionInformation,
-			Version byondVersion,
+			ByondVersion byondVersion,
 			DateTimeOffset? estimatedCompletionTime,
 			string gitHubOwner,
 			string gitHubRepo,
@@ -271,9 +272,7 @@ namespace Tgstation.Server.Host.Components.Chat.Providers
 						commitInsert,
 						testmergeInsert,
 						remoteCommitInsert,
-						byondVersion.Build > 0
-							? byondVersion.ToString()
-							: $"{byondVersion.Major}.{byondVersion.Minor}",
+						byondVersion.ToString(),
 						estimatedCompletionTime.HasValue
 							? $" ETA: {estimatedCompletionTime - DateTimeOffset.UtcNow}"
 							: String.Empty),

src/Tgstation.Server.Host/Components/Chat/Providers/Provider.cs

@@ -5,6 +5,7 @@ using System.Threading.Tasks;
 
 using Microsoft.Extensions.Logging;
 
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Api.Rights;
 using Tgstation.Server.Host.Components.Interop;
 using Tgstation.Server.Host.Jobs;
@@ -182,8 +183,8 @@ namespace Tgstation.Server.Host.Components.Chat.Providers
 
 		/// <inheritdoc />
 		public abstract ValueTask<Func<string, string, ValueTask<Func<bool, ValueTask>>>> SendUpdateMessage(
-			RevisionInformation revisionInformation,
-			Version byondVersion,
+			Models.RevisionInformation revisionInformation,
+			ByondVersion byondVersion,
 			DateTimeOffset? estimatedCompletionTime,
 			string gitHubOwner,
 			string gitHubRepo,
@@ -273,7 +274,7 @@ namespace Tgstation.Server.Host.Components.Chat.Providers
 						connectNow = false;
 					if (!Connected)
 					{
-						var job = new Job
+						var job = new Models.Job
 						{
 							Description = $"Reconnect chat bot: {ChatBot.Name}",
 							CancelRight = (ulong)ChatBotRights.WriteEnabled,

src/Tgstation.Server.Host/Components/Deployment/DmbFactory.cs

@@ -245,6 +245,12 @@ namespace Tgstation.Server.Host.Components.Deployment
 						.ThenInclude(x => x.MergedBy)
 					.FirstAsync(cancellationToken)); // can't wait to see that query
 
+			if (!Api.Models.Internal.ByondVersion.TryParse(compileJob.ByondVersion, out var byondVersion))
+			{
+				logger.LogWarning("Error loading compile job, bad BYOND version: {0}", compileJob.ByondVersion);
+				return null; // omae wa mou shinderu
+			}
+
 			if (!compileJob.Job.StoppedAt.HasValue)
 			{
 				// This happens when we're told to load the compile job that is currently finished up
@@ -262,7 +268,7 @@ namespace Tgstation.Server.Host.Components.Deployment
 					CleanRegisteredCompileJob(compileJob);
 			}
 
-			var newProvider = new DmbProvider(compileJob, ioManager, CleanupAction);
+			var newProvider = new DmbProvider(compileJob, byondVersion, ioManager, CleanupAction);
 			try
 			{
 				const string LegacyADirectoryName = "A";
@@ -299,7 +305,7 @@ namespace Tgstation.Server.Host.Components.Deployment
 					// rebuild the provider because it's using the legacy style directories
 					// Don't dispose it
 					logger.LogDebug("Creating legacy two folder .dmb provider targeting {aDirName} directory...", LegacyADirectoryName);
-					newProvider = new DmbProvider(compileJob, ioManager, CleanupAction, Path.DirectorySeparatorChar + LegacyADirectoryName);
+					newProvider = new DmbProvider(compileJob, byondVersion, ioManager, CleanupAction, Path.DirectorySeparatorChar + LegacyADirectoryName);
 				}
 
 				lock (jobLockCounts)

src/Tgstation.Server.Host/Components/Deployment/DmbProvider.cs

@@ -1,7 +1,7 @@
 using System;
 
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Host.IO;
-using Tgstation.Server.Host.Models;
 
 namespace Tgstation.Server.Host.Components.Deployment
 {
@@ -14,10 +14,11 @@ namespace Tgstation.Server.Host.Components.Deployment
 		/// <inheritdoc />
 		public string Directory => ioManager.ResolvePath(CompileJob.DirectoryName.ToString() + directoryAppend);
 
-		/// <summary>
-		/// The <see cref="CompileJob"/> for the <see cref="DmbProvider"/>.
-		/// </summary>
-		public CompileJob CompileJob { get; }
+		/// <inheritdoc />
+		public Models.CompileJob CompileJob { get; }
+
+		/// <inheritdoc />
+		public ByondVersion ByondVersion { get; }
 
 		/// <summary>
 		/// The <see cref="IIOManager"/> for the <see cref="DmbProvider"/>.
@@ -25,7 +26,7 @@ namespace Tgstation.Server.Host.Components.Deployment
 		readonly IIOManager ioManager;
 
 		/// <summary>
-		/// Extra path to add to the end of <see cref="Api.Models.Internal.CompileJob.DirectoryName"/>.
+		/// Extra path to add to the end of <see cref="CompileJob.DirectoryName"/>.
 		/// </summary>
 		readonly string directoryAppend;
 
@@ -38,12 +39,14 @@ namespace Tgstation.Server.Host.Components.Deployment
 		/// Initializes a new instance of the <see cref="DmbProvider"/> class.
 		/// </summary>
 		/// <param name="compileJob">The value of <see cref="CompileJob"/>.</param>
+		/// <param name="byondVersion">The value of <see cref="ByondVersion"/>.</param>
 		/// <param name="ioManager">The value of <see cref="ioManager"/>.</param>
 		/// <param name="onDispose">The value of <see cref="onDispose"/>.</param>
 		/// <param name="directoryAppend">The optional value of <see cref="directoryAppend"/>.</param>
-		public DmbProvider(CompileJob compileJob, IIOManager ioManager, Action onDispose, string directoryAppend = null)
+		public DmbProvider(Models.CompileJob compileJob, ByondVersion byondVersion, IIOManager ioManager, Action onDispose, string directoryAppend = null)
 		{
 			CompileJob = compileJob ?? throw new ArgumentNullException(nameof(compileJob));
+			ByondVersion = byondVersion ?? throw new ArgumentNullException(nameof(byondVersion));
 			this.ioManager = ioManager ?? throw new ArgumentNullException(nameof(ioManager));
 			this.onDispose = onDispose ?? throw new ArgumentNullException(nameof(onDispose));
 			this.directoryAppend = directoryAppend ?? String.Empty;

src/Tgstation.Server.Host/Components/Deployment/DreamMaker.cs

@@ -553,7 +553,7 @@ namespace Tgstation.Server.Host.Components.Deployment
 		/// <param name="job">The <see cref="CompileJob"/> to run and populate.</param>
 		/// <param name="dreamMakerSettings">The <see cref="Api.Models.Internal.DreamMakerSettings"/> to use.</param>
 		/// <param name="launchParameters">The <see cref="DreamDaemonLaunchParameters"/> to use.</param>
-		/// <param name="byondLock">The <see cref="IByondExecutableLock"/> to use.</param>
+		/// <param name="byondLock">The <see cref="IEngineExecutableLock"/> to use.</param>
 		/// <param name="repository">The <see cref="IRepository"/> to use.</param>
 		/// <param name="remoteDeploymentManager">The <see cref="IRemoteDeploymentManager"/> to use.</param>
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
@@ -563,7 +563,7 @@ namespace Tgstation.Server.Host.Components.Deployment
 			Models.CompileJob job,
 			Api.Models.Internal.DreamMakerSettings dreamMakerSettings,
 			DreamDaemonLaunchParameters launchParameters,
-			IByondExecutableLock byondLock,
+			IEngineExecutableLock byondLock,
 			IRepository repository,
 			IRemoteDeploymentManager remoteDeploymentManager,
 			CancellationToken cancellationToken)
@@ -591,7 +591,7 @@ namespace Tgstation.Server.Host.Components.Deployment
 					{
 						resolvedOutputDirectory,
 						repoOrigin.ToString(),
-						$"{byondLock.Version.Major}.{byondLock.Version.Minor}",
+						byondLock.Version.ToString(),
 					},
 					true,
 					cancellationToken);
@@ -630,14 +630,14 @@ namespace Tgstation.Server.Host.Components.Deployment
 					{
 						resolvedOutputDirectory,
 						repoOrigin.ToString(),
-						$"{byondLock.Version.Major}.{byondLock.Version.Minor}",
+						byondLock.Version.ToString(),
 					},
 					true,
 					cancellationToken);
 
 				// run compiler
 				progressReporter.StageName = "Running DreamMaker";
-				var exitCode = await RunDreamMaker(byondLock.DreamMakerPath, job, cancellationToken);
+				var compileSuceeded = await RunDreamMaker(byondLock, job, cancellationToken);
 
 				// Session takes ownership of the lock and Disposes it so save this for later
 				var byondVersion = byondLock.Version;
@@ -645,10 +645,10 @@ namespace Tgstation.Server.Host.Components.Deployment
 				// verify api
 				try
 				{
-					if (exitCode != 0)
+					if (!compileSuceeded)
 						throw new JobException(
 							ErrorCode.DreamMakerExitCode,
-							new JobException($"Exit code: {exitCode}{Environment.NewLine}{Environment.NewLine}{job.Output}"));
+							new JobException($"Compilation failed:{Environment.NewLine}{Environment.NewLine}{job.Output}"));
 
 					progressReporter.StageName = "Validating DMAPI";
 					await VerifyApi(
@@ -670,7 +670,7 @@ namespace Tgstation.Server.Host.Components.Deployment
 						new List<string>
 						{
 							resolvedOutputDirectory,
-							exitCode == 0 ? "1" : "0",
+							compileSuceeded ? "1" : "0",
 							byondVersion.ToString(),
 						},
 						true,
@@ -769,7 +769,7 @@ namespace Tgstation.Server.Host.Components.Deployment
 		/// <param name="timeout">The timeout in seconds for validation.</param>
 		/// <param name="securityLevel">The <see cref="DreamDaemonSecurity"/> level to use to validate the API.</param>
 		/// <param name="job">The <see cref="CompileJob"/> for the operation.</param>
-		/// <param name="byondLock">The current <see cref="IByondExecutableLock"/>.</param>
+		/// <param name="byondLock">The current <see cref="IEngineExecutableLock"/>.</param>
 		/// <param name="portToUse">The port to use for API validation.</param>
 		/// <param name="requireValidate">If the API validation is required to complete the deployment.</param>
 		/// <param name="logOutput">If output should be logged to the DreamDaemon Diagnostics folder.</param>
@@ -779,7 +779,7 @@ namespace Tgstation.Server.Host.Components.Deployment
 			uint timeout,
 			DreamDaemonSecurity securityLevel,
 			Models.CompileJob job,
-			IByondExecutableLock byondLock,
+			IEngineExecutableLock byondLock,
 			ushort portToUse,
 			bool requireValidate,
 			bool logOutput,
@@ -803,7 +803,11 @@ namespace Tgstation.Server.Host.Components.Deployment
 			job.MinimumSecurityLevel = securityLevel; // needed for the TempDmbProvider
 
 			ApiValidationStatus validationStatus;
-			using (var provider = new TemporaryDmbProvider(ioManager.ResolvePath(job.DirectoryName.ToString()), String.Concat(job.DmeName, DmbExtension), job))
+			using (var provider = new TemporaryDmbProvider(
+				ioManager.ResolvePath(job.DirectoryName.ToString()),
+				String.Concat(job.DmeName, DmbExtension),
+				job,
+				byondLock.Version))
 			await using (var controller = await sessionControllerFactory.LaunchNew(provider, byondLock, launchParameters, true, cancellationToken))
 			{
 				var launchResult = await controller.LaunchResult.WaitAsync(cancellationToken);
@@ -853,33 +857,46 @@ namespace Tgstation.Server.Host.Components.Deployment
 		/// <summary>
 		/// Compiles a .dme with DreamMaker.
 		/// </summary>
-		/// <param name="dreamMakerPath">The path to the DreamMaker executable.</param>
+		/// <param name="engineLock">The <see cref="IEngineExecutableLock"/> to use.</param>
 		/// <param name="job">The <see cref="CompileJob"/> for the operation.</param>
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
-		/// <returns>A <see cref="ValueTask"/> representing the running operation.</returns>
-		async ValueTask<int> RunDreamMaker(string dreamMakerPath, Models.CompileJob job, CancellationToken cancellationToken)
+		/// <returns>A <see cref="ValueTask{TResult}"/> resulting in <see langword="true"/> if compilation succeeded, <see langword="false"/> otherwise.</returns>
+		async ValueTask<bool> RunDreamMaker(IEngineExecutableLock engineLock, Models.CompileJob job, CancellationToken cancellationToken)
 		{
-			await using var dm = processExecutor.LaunchProcess(
-				dreamMakerPath,
-				ioManager.ResolvePath(
-					job.DirectoryName.ToString()),
-				$"-clean {job.DmeName}.{DmeExtension}",
-				readStandardHandles: true,
-				noShellExecute: true);
+			var arguments = engineLock.FormatCompilerArguments($"{job.DmeName}.{DmeExtension}");
+			bool result;
+			if (arguments == null)
+			{
+				logger.LogTrace("Engine lock says compilation isn't necessary.");
+				job.Output = $"{engineLock.Version.Engine} does not require compilation.";
+				result = true;
+			}
+			else
+			{
+				await using var dm = processExecutor.LaunchProcess(
+					engineLock.CompilerExePath,
+					ioManager.ResolvePath(
+						job.DirectoryName.ToString()),
+					arguments,
+					readStandardHandles: true,
+					noShellExecute: true);
 
-			if (sessionConfiguration.LowPriorityDeploymentProcesses)
-				dm.AdjustPriority(false);
+				if (sessionConfiguration.LowPriorityDeploymentProcesses)
+					dm.AdjustPriority(false);
 
-			int exitCode;
-			using (cancellationToken.Register(() => dm.Terminate()))
-				exitCode = (await dm.Lifetime).Value;
-			cancellationToken.ThrowIfCancellationRequested();
+				int exitCode;
+				using (cancellationToken.Register(() => dm.Terminate()))
+					exitCode = (await dm.Lifetime).Value;
+				cancellationToken.ThrowIfCancellationRequested();
+
+				logger.LogDebug("DreamMaker exit code: {exitCode}", exitCode);
+				job.Output = $"{await dm.GetCombinedOutput(cancellationToken)}{Environment.NewLine}{Environment.NewLine}Exit Code: {exitCode}";
+				logger.LogDebug("DreamMaker output: {newLine}{output}", Environment.NewLine, job.Output);
+				result = exitCode == 0;
+			}
 
-			logger.LogDebug("DreamMaker exit code: {exitCode}", exitCode);
-			job.Output = await dm.GetCombinedOutput(cancellationToken);
 			currentDreamMakerOutput = job.Output;
-			logger.LogDebug("DreamMaker output: {newLine}{output}", Environment.NewLine, job.Output);
-			return exitCode;
+			return result;
 		}
 
 		/// <summary>

src/Tgstation.Server.Host/Components/Deployment/IDmbProvider.cs

@@ -1,6 +1,6 @@
 using System;
 
-using Tgstation.Server.Host.Models;
+using Tgstation.Server.Api.Models.Internal;
 
 namespace Tgstation.Server.Host.Components.Deployment
 {
@@ -22,7 +22,12 @@ namespace Tgstation.Server.Host.Components.Deployment
 		/// <summary>
 		/// The <see cref="CompileJob"/> of the .dmb.
 		/// </summary>
-		CompileJob CompileJob { get; }
+		Models.CompileJob CompileJob { get; }
+
+		/// <summary>
+		/// The <see cref="Api.Models.Internal.ByondVersion"/> used to build the .dmb.
+		/// </summary>
+		ByondVersion ByondVersion { get; }
 
 		/// <summary>
 		/// Disposing the <see cref="IDmbProvider"/> won't cause a cleanup of the working directory.

src/Tgstation.Server.Host/Components/Deployment/SwappableDmbProvider.cs

@@ -2,8 +2,8 @@
 using System.Threading;
 using System.Threading.Tasks;
 
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Host.IO;
-using Tgstation.Server.Host.Models;
 
 namespace Tgstation.Server.Host.Components.Deployment
 {
@@ -24,7 +24,10 @@ namespace Tgstation.Server.Host.Components.Deployment
 		public string Directory => ioManager.ResolvePath(LiveGameDirectory);
 
 		/// <inheritdoc />
-		public CompileJob CompileJob => baseProvider.CompileJob;
+		public Models.CompileJob CompileJob => baseProvider.CompileJob;
+
+		/// <inheritdoc />
+		public ByondVersion ByondVersion => baseProvider.ByondVersion;
 
 		/// <summary>
 		/// If <see cref="MakeActive(CancellationToken)"/> has been run.

src/Tgstation.Server.Host/Components/Deployment/TemporaryDmbProvider.cs

@@ -1,6 +1,6 @@
 using System;
 
-using Tgstation.Server.Host.Models;
+using Tgstation.Server.Api.Models.Internal;
 
 namespace Tgstation.Server.Host.Components.Deployment
 {
@@ -16,7 +16,10 @@ namespace Tgstation.Server.Host.Components.Deployment
 		public string Directory { get; }
 
 		/// <inheritdoc />
-		public CompileJob CompileJob { get; }
+		public Models.CompileJob CompileJob { get; }
+
+		/// <inheritdoc />
+		public ByondVersion ByondVersion { get; }
 
 		/// <summary>
 		/// Initializes a new instance of the <see cref="TemporaryDmbProvider"/> class.
@@ -24,11 +27,13 @@ namespace Tgstation.Server.Host.Components.Deployment
 		/// <param name="directory">The value of <see cref="Directory"/>.</param>
 		/// <param name="dmb">The value of <see cref="DmbName"/>.</param>
 		/// <param name="compileJob">The value of <see cref="CompileJob"/>.</param>
-		public TemporaryDmbProvider(string directory, string dmb, CompileJob compileJob)
+		/// <param name="byondVersion">The value of <see cref="ByondVersion"/>.</param>
+		public TemporaryDmbProvider(string directory, string dmb, Models.CompileJob compileJob, ByondVersion byondVersion)
 		{
 			DmbName = dmb ?? throw new ArgumentNullException(nameof(dmb));
 			Directory = directory ?? throw new ArgumentNullException(nameof(directory));
 			CompileJob = compileJob ?? throw new ArgumentNullException(nameof(compileJob));
+			ByondVersion = byondVersion ?? throw new ArgumentNullException(nameof(byondVersion));
 		}
 
 		/// <inheritdoc />

src/Tgstation.Server.Host/Components/Session/ISessionControllerFactory.cs

@@ -16,14 +16,14 @@ namespace Tgstation.Server.Host.Components.Session
 		/// Create a <see cref="ISessionController"/> from a freshly launch DreamDaemon instance.
 		/// </summary>
 		/// <param name="dmbProvider">The <see cref="IDmbProvider"/> to use.</param>
-		/// <param name="currentByondLock">The current <see cref="IByondExecutableLock"/> if any.</param>
+		/// <param name="currentByondLock">The current <see cref="IEngineExecutableLock"/> if any.</param>
 		/// <param name="launchParameters">The <see cref="DreamDaemonLaunchParameters"/> to use. <see cref="DreamDaemonLaunchParameters.SecurityLevel"/> will be updated with the minumum required security level for the launch.</param>
 		/// <param name="apiValidate">If the <see cref="ISessionController"/> should only validate the DMAPI then exit.</param>
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
 		/// <returns>A <see cref="ValueTask{TResult}"/> resulting in a new <see cref="ISessionController"/>.</returns>
 		ValueTask<ISessionController> LaunchNew(
 			IDmbProvider dmbProvider,
-			IByondExecutableLock currentByondLock,
+			IEngineExecutableLock currentByondLock,
 			DreamDaemonLaunchParameters launchParameters,
 			bool apiValidate,
 			CancellationToken cancellationToken);

src/Tgstation.Server.Host/Components/Session/SessionController.cs

@@ -123,9 +123,9 @@ namespace Tgstation.Server.Host.Components.Session
 		readonly IProcess process;
 
 		/// <summary>
-		/// The <see cref="IByondExecutableLock"/> for the <see cref="SessionController"/>.
+		/// The <see cref="IEngineExecutableLock"/> for the <see cref="SessionController"/>.
 		/// </summary>
-		readonly IByondExecutableLock byondLock;
+		readonly IEngineExecutableLock byondLock;
 
 		/// <summary>
 		/// The <see cref="IChatTrackingContext"/> for the <see cref="SessionController"/>.
@@ -244,7 +244,7 @@ namespace Tgstation.Server.Host.Components.Session
 			ReattachInformation reattachInformation,
 			Api.Models.Instance metadata,
 			IProcess process,
-			IByondExecutableLock byondLock,
+			IEngineExecutableLock byondLock,
 			global::Byond.TopicSender.ITopicClient byondTopicSender,
 			IChatTrackingContext chatTrackingContext,
 			IBridgeRegistrar bridgeRegistrar,

src/Tgstation.Server.Host/Components/Session/SessionControllerFactory.cs

@@ -6,8 +6,6 @@ using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 
-using Byond.TopicSender;
-
 using Microsoft.Extensions.Logging;
 
 using Tgstation.Server.Api.Models;
@@ -128,38 +126,6 @@ namespace Tgstation.Server.Host.Components.Session
 		/// </summary>
 		readonly Api.Models.Instance instance;
 
-		/// <summary>
-		/// Change a given <paramref name="securityLevel"/> into the appropriate DreamDaemon command line word.
-		/// </summary>
-		/// <param name="securityLevel">The <see cref="DreamDaemonSecurity"/> level to change.</param>
-		/// <returns>A <see cref="string"/> representation of the command line parameter.</returns>
-		static string SecurityWord(DreamDaemonSecurity securityLevel)
-		{
-			return securityLevel switch
-			{
-				DreamDaemonSecurity.Safe => "safe",
-				DreamDaemonSecurity.Trusted => "trusted",
-				DreamDaemonSecurity.Ultrasafe => "ultrasafe",
-				_ => throw new ArgumentOutOfRangeException(nameof(securityLevel), securityLevel, String.Format(CultureInfo.InvariantCulture, "Bad DreamDaemon security level: {0}", securityLevel)),
-			};
-		}
-
-		/// <summary>
-		/// Change a given <paramref name="visibility"/> into the appropriate DreamDaemon command line word.
-		/// </summary>
-		/// <param name="visibility">The <see cref="DreamDaemonVisibility"/> level to change.</param>
-		/// <returns>A <see cref="string"/> representation of the command line parameter.</returns>
-		static string VisibilityWord(DreamDaemonVisibility visibility)
-		{
-			return visibility switch
-			{
-				DreamDaemonVisibility.Public => "public",
-				DreamDaemonVisibility.Private => "private",
-				DreamDaemonVisibility.Invisible => "invisible",
-				_ => throw new ArgumentOutOfRangeException(nameof(visibility), visibility, String.Format(CultureInfo.InvariantCulture, "Bad DreamDaemon visibility level: {0}", visibility)),
-			};
-		}
-
 		/// <summary>
 		/// Check if a given <paramref name="port"/> can be bound to.
 		/// </summary>
@@ -242,7 +208,7 @@ namespace Tgstation.Server.Host.Components.Session
 		#pragma warning disable CA1506 // TODO: Decomplexify
 		public async ValueTask<ISessionController> LaunchNew(
 			IDmbProvider dmbProvider,
-			IByondExecutableLock currentByondLock,
+			IEngineExecutableLock currentByondLock,
 			DreamDaemonLaunchParameters launchParameters,
 			bool apiValidate,
 			CancellationToken cancellationToken)
@@ -274,7 +240,7 @@ namespace Tgstation.Server.Host.Components.Session
 
 			// get the byond lock
 			var byondLock = currentByondLock ?? await byond.UseExecutables(
-				Version.Parse(dmbProvider.CompileJob.ByondVersion),
+				dmbProvider.ByondVersion,
 				gameIOManager.ConcatPath(dmbProvider.Directory, dmbProvider.DmbName),
 				cancellationToken);
 			try
@@ -289,7 +255,7 @@ namespace Tgstation.Server.Host.Components.Session
 				string outputFilePath = null;
 				var preserveLogFile = true;
 
-				var cliSupported = byondLock.SupportsCli;
+				var hasStandardOutput = byondLock.HasStandardOutput;
 				if (launchParameters.LogOutput.Value)
 				{
 					var now = DateTimeOffset.UtcNow;
@@ -302,7 +268,7 @@ namespace Tgstation.Server.Host.Components.Session
 
 					logger.LogInformation("Logging DreamDaemon output to {path}...", outputFilePath);
 				}
-				else if (!cliSupported)
+				else if (!hasStandardOutput)
 				{
 					outputFilePath = gameIOManager.ConcatPath(dmbProvider.Directory, $"{Guid.NewGuid()}.dd.log");
 					preserveLogFile = false;
@@ -310,17 +276,12 @@ namespace Tgstation.Server.Host.Components.Session
 
 				var accessIdentifier = cryptographySuite.GetSecureString();
 
-				var byondTopicSender = topicClientFactory.CreateTopicClient(
-					TimeSpan.FromMilliseconds(
-						launchParameters.TopicRequestTimeout.Value));
-
 				if (!apiValidate && dmbProvider.CompileJob.DMApiVersion == null)
 					logger.LogDebug("Session will have no DMAPI support!");
 
 				// launch dd
-				var process = await CreateDreamDaemonProcess(
+				var process = await CreateGameServerProcess(
 					dmbProvider,
-					byondTopicSender,
 					byondLock,
 					launchParameters,
 					accessIdentifier,
@@ -347,6 +308,10 @@ namespace Tgstation.Server.Host.Components.Session
 							accessIdentifier,
 							launchParameters.Port.Value);
 
+						var byondTopicSender = topicClientFactory.CreateTopicClient(
+							TimeSpan.FromMilliseconds(
+								launchParameters.TopicRequestTimeout.Value));
+
 						var sessionController = new SessionController(
 							reattachInformation,
 							instance,
@@ -362,7 +327,7 @@ namespace Tgstation.Server.Host.Components.Session
 							() => LogDDOutput(
 								process,
 								outputFilePath,
-								cliSupported,
+								hasStandardOutput,
 								preserveLogFile,
 								CancellationToken.None), // DCT: None available
 							launchParameters.StartupTimeout,
@@ -406,7 +371,7 @@ namespace Tgstation.Server.Host.Components.Session
 			logger.LogTrace("Begin session reattach...");
 			var byondTopicSender = topicClientFactory.CreateTopicClient(reattachInformation.TopicRequestTimeout);
 			var byondLock = await byond.UseExecutables(
-				Version.Parse(reattachInformation.Dmb.CompileJob.ByondVersion),
+				reattachInformation.Dmb.ByondVersion,
 				null, // Doesn't matter if it's trusted or not on reattach
 				cancellationToken);
 
@@ -423,7 +388,7 @@ namespace Tgstation.Server.Host.Components.Session
 
 				try
 				{
-					if (!byondLock.SupportsCli)
+					if (byondLock.PromptsForNetworkAccess)
 						networkPromptReaper.RegisterProcess(process);
 
 					var chatTrackingContext = chat.CreateTrackingContext();
@@ -479,60 +444,45 @@ namespace Tgstation.Server.Host.Components.Session
 		}
 
 		/// <summary>
-		/// Creates the DreamDaemon <see cref="IProcess"/>.
+		/// Creates the game server <see cref="IProcess"/>.
 		/// </summary>
 		/// <param name="dmbProvider">The <see cref="IDmbProvider"/>.</param>
-		/// <param name="byondTopicSender">The <see cref="ITopicClient"/> to use for sanitization.</param>
-		/// <param name="byondLock">The <see cref="IByondExecutableLock"/>.</param>
+		/// <param name="byondLock">The <see cref="IEngineExecutableLock"/>.</param>
 		/// <param name="launchParameters">The <see cref="DreamDaemonLaunchParameters"/>.</param>
 		/// <param name="accessIdentifier">The secure string to use for the session.</param>
 		/// <param name="logFilePath">The path to log DreamDaemon output to.</param>
 		/// <param name="apiValidate">If we are only validating the DMAPI then exiting.</param>
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
 		/// <returns>A <see cref="ValueTask{TResult}"/> resulting in the DreamDaemon <see cref="IProcess"/>.</returns>
-		async ValueTask<IProcess> CreateDreamDaemonProcess(
+		async ValueTask<IProcess> CreateGameServerProcess(
 			IDmbProvider dmbProvider,
-			ITopicClient byondTopicSender,
-			IByondExecutableLock byondLock,
+			IEngineExecutableLock byondLock,
 			DreamDaemonLaunchParameters launchParameters,
 			string accessIdentifier,
 			string logFilePath,
 			bool apiValidate,
 			CancellationToken cancellationToken)
 		{
-			// set command line options
-			// more sanitization here cause it uses the same scheme
-			var parameters = $"{DMApiConstants.ParamApiVersion}={byondTopicSender.SanitizeString(DMApiConstants.InteropVersion.Semver().ToString())}&{byondTopicSender.SanitizeString(DMApiConstants.ParamServerPort)}={serverPortProvider.HttpApiPort}&{byondTopicSender.SanitizeString(DMApiConstants.ParamAccessIdentifier)}={byondTopicSender.SanitizeString(accessIdentifier)}";
-
-			if (!String.IsNullOrEmpty(launchParameters.AdditionalParameters))
-				parameters = $"{parameters}&{launchParameters.AdditionalParameters}";
-
 			// important to run on all ports to allow port changing
-			var arguments = String.Format(
-				CultureInfo.InvariantCulture,
-				"{0} -port {1} -ports 1-65535 {2}-close -verbose -{3} -{4}{5}{6}{7} -params \"{8}\"",
-				dmbProvider.DmbName,
-				launchParameters.Port.Value,
-				launchParameters.AllowWebClient.Value ? "-webclient " : String.Empty,
-				SecurityWord(launchParameters.SecurityLevel.Value),
-				VisibilityWord(launchParameters.Visibility.Value),
-				!byondLock.SupportsCli
-					? $" -logself -log {logFilePath}"
-					: String.Empty, // DD doesn't output anything if -logself is set???
-				launchParameters.StartProfiler.Value
-					? " -profile"
-					: String.Empty,
-				byondLock.SupportsMapThreads && launchParameters.MapThreads.Value != 0
-					? $" -map-threads {launchParameters.MapThreads.Value}"
-					: String.Empty,
-				parameters);
+			var arguments = byondLock.FormatServerArguments(
+				dmbProvider,
+				new Dictionary<string, string>
+				{
+					{ DMApiConstants.ParamApiVersion, DMApiConstants.InteropVersion.Semver().ToString() },
+					{ DMApiConstants.ParamServerPort, serverPortProvider.HttpApiPort.ToString(CultureInfo.InvariantCulture) },
+					{ DMApiConstants.ParamAccessIdentifier, accessIdentifier },
+				},
+				launchParameters,
+				!byondLock.HasStandardOutput
+					? logFilePath
+					: null);
 
 			var process = processExecutor.LaunchProcess(
-				byondLock.DreamDaemonPath,
+				byondLock.ServerExePath,
 				dmbProvider.Directory,
 				arguments,
 				logFilePath,
-				byondLock.SupportsCli,
+				byondLock.HasStandardOutput,
 				true);
 
 			try
@@ -545,7 +495,7 @@ namespace Tgstation.Server.Host.Components.Session
 				else if (sessionConfiguration.LowPriorityDeploymentProcesses)
 					process.AdjustPriority(false);
 
-				if (!byondLock.SupportsCli)
+				if (!byondLock.HasStandardOutput)
 					networkPromptReaper.RegisterProcess(process);
 
 				// If this isnt a staging DD (From a Deployment), fire off an event

src/Tgstation.Server.Host/Controllers/ByondController.cs

@@ -43,7 +43,7 @@ namespace Tgstation.Server.Host.Controllers
 		/// </summary>
 		/// <param name="version">The <see cref="Version"/> to normalize.</param>
 		/// <returns>The normalized <see cref="Version"/>. May be a reference to <paramref name="version"/>.</returns>
-		static Version NormalizeVersion(Version version) => version.Build == 0 ? new Version(version.Major, version.Minor) : version;
+		static Version NormalizeByondVersion(Version version) => version.Build == 0 ? new Version(version.Major, version.Minor) : version;
 
 		/// <summary>
 		/// Initializes a new instance of the <see cref="ByondController"/> class.
@@ -72,23 +72,26 @@ namespace Tgstation.Server.Host.Controllers
 		}
 
 		/// <summary>
-		/// Gets the active <see cref="ByondResponse.Version"/>.
+		/// Gets the active <see cref="Api.Models.Internal.ByondVersion"/>.
 		/// </summary>
 		/// <returns>A <see cref="ValueTask{TResult}"/> resulting in the <see cref="IActionResult"/> for the operation.</returns>
 		/// <response code="200">Retrieved version information successfully.</response>
+		/// <response code="409">No BYOND versions installed.</response>
 		[HttpGet]
 		[TgsAuthorize(ByondRights.ReadActive)]
 		[ProducesResponseType(typeof(ByondResponse), 200)]
+		[ProducesResponseType(typeof(ErrorMessageResponse), 409)]
 		public ValueTask<IActionResult> Read()
 			=> WithComponentInstance(instance =>
 				ValueTask.FromResult<IActionResult>(
-					Json(new ByondResponse
-					{
-						Version = instance.ByondManager.ActiveVersion,
-					})));
+					instance.ByondManager.ActiveVersion != null
+						? Json(
+							new ByondResponse(
+								instance.ByondManager.ActiveVersion))
+						: Conflict(new ErrorMessageResponse(ErrorCode.ResourceNotPresent))));
 
 		/// <summary>
-		/// Lists installed <see cref="ByondResponse.Version"/>s.
+		/// Lists installed <see cref="Api.Models.Internal.ByondVersion"/>s.
 		/// </summary>
 		/// <param name="page">The current page.</param>
 		/// <param name="pageSize">The page size.</param>
@@ -106,10 +109,7 @@ namespace Tgstation.Server.Host.Controllers
 							instance
 								.ByondManager
 								.InstalledVersions
-								.Select(x => new ByondResponse
-								{
-									Version = x,
-								})
+								.Select(x => new ByondResponse(x))
 								.AsQueryable()
 								.OrderBy(x => x.Version))),
 					null,
@@ -126,27 +126,42 @@ namespace Tgstation.Server.Host.Controllers
 		/// <response code="200">Switched active version successfully.</response>
 		/// <response code="202">Created <see cref="Job"/> to install and switch active version successfully.</response>
 		[HttpPost]
-		[TgsAuthorize(ByondRights.InstallOfficialOrChangeActiveVersion | ByondRights.InstallCustomVersion)]
+		[TgsAuthorize(
+			ByondRights.InstallOfficialOrChangeActiveByondVersion
+			| ByondRights.InstallCustomByondVersion
+			| ByondRights.InstallOfficialOrChangeActiveOpenDreamVersion
+			| ByondRights.InstallCustomOpenDreamVersion)]
 		[ProducesResponseType(typeof(ByondInstallResponse), 200)]
 		[ProducesResponseType(typeof(ByondInstallResponse), 202)]
-#pragma warning disable CA1506 // TODO: Decomplexify
+#pragma warning disable CA1502 // TODO: Decomplexify
+#pragma warning disable CA1506
 		public async ValueTask<IActionResult> Update([FromBody] ByondVersionRequest model, CancellationToken cancellationToken)
 #pragma warning restore CA1506
+#pragma warning restore CA1502
 		{
 			ArgumentNullException.ThrowIfNull(model);
 
 			var uploadingZip = model.UploadCustomZip == true;
+			var isByondEngine = model.Engine.Value == EngineType.Byond;
 
-			if (model.Version == null
-				|| model.Version.Revision != -1
-				|| (uploadingZip && model.Version.Build > 0))
+			if ((isByondEngine && (model.Version.Revision != -1 || (uploadingZip && model.Version.Build > 0) || model.SourceCommittish != null || model.SourceRepository != null))
+				|| (!isByondEngine && (model.Version != null || String.IsNullOrWhiteSpace(model.SourceCommittish))))
 				return BadRequest(new ErrorMessageResponse(ErrorCode.ModelValidationFailure));
 
-			var version = NormalizeVersion(model.Version);
+			Uri sourceRepo;
+			if (isByondEngine)
+			{
+				model.Version = NormalizeByondVersion(model.Version);
+				sourceRepo = null;
+			}
+			else
+			{
+				sourceRepo = model.SourceRepository ?? new Uri("https://github.com/OpenDreamProject/OpenDream");
+			}
 
 			var userByondRights = AuthenticationContext.InstancePermissionSet.ByondRights.Value;
-			if ((!userByondRights.HasFlag(ByondRights.InstallOfficialOrChangeActiveVersion) && !uploadingZip)
-				|| (!userByondRights.HasFlag(ByondRights.InstallCustomVersion) && uploadingZip))
+			if ((!userByondRights.HasFlag(ByondRights.InstallOfficialOrChangeActiveByondVersion) && !uploadingZip)
+				|| (!userByondRights.HasFlag(ByondRights.InstallCustomByondVersion) && uploadingZip))
 				return Forbid();
 
 			// remove cruff fields
@@ -155,44 +170,50 @@ namespace Tgstation.Server.Host.Controllers
 				async instance =>
 				{
 					var byondManager = instance.ByondManager;
-					var versionAlreadyInstalled = !uploadingZip && byondManager.InstalledVersions.Any(x => x == version);
+					var versionAlreadyInstalled = !uploadingZip && byondManager.InstalledVersions.Any(x => x.Equals(model));
 					if (versionAlreadyInstalled)
 					{
 						Logger.LogInformation(
-							"User ID {userId} changing instance ID {instanceId} BYOND version to {newByondVersion}",
+							"User ID {userId} changing instance ID {instanceId} {engineType} version to {newByondVersion}",
 							AuthenticationContext.User.Id,
 							Instance.Id,
-							version);
+							model.Engine,
+							model.Version);
 
 						try
 						{
-							await byondManager.ChangeVersion(null, version, null, false, cancellationToken);
+							await byondManager.ChangeVersion(null, model, null, false, cancellationToken);
 						}
 						catch (InvalidOperationException ex)
 						{
 							Logger.LogDebug(
 								ex,
-								"Race condition: BYOND version {version} uninstalled before we could switch to it. Creating install job instead...",
-								version);
+								"Race condition: {engineType} version {version} uninstalled before we could switch to it. Creating install job instead...",
+								model.Engine.Value,
+								model.Version);
 							versionAlreadyInstalled = false;
 						}
 					}
 
 					if (!versionAlreadyInstalled)
 					{
-						if (version.Build > 0)
+						if (model.Version.Build > 0)
 							return BadRequest(new ErrorMessageResponse(ErrorCode.ByondNonExistentCustomVersion));
 
 						Logger.LogInformation(
-							"User ID {userId} installing BYOND version to {newByondVersion} on instance ID {instanceId}",
+							"User ID {userId} installing {engineType} version {newByondVersion}{sourceCommittish} on instance ID {instanceId}",
 							AuthenticationContext.User.Id,
-							version,
+							model.Engine.Value,
+							model.Version,
+							model.SourceCommittish != null
+								? $" ({model.SourceCommittish})"
+								: String.Empty,
 							Instance.Id);
 
 						// run the install through the job manager
 						var job = new Job
 						{
-							Description = $"Install {(!uploadingZip ? String.Empty : "custom ")}BYOND version {version}",
+							Description = $"Install {(!uploadingZip ? String.Empty : "custom ")}{model.Engine.Value} version {model.Version}",
 							StartedBy = AuthenticationContext.User,
 							CancelRightsType = RightsType.Byond,
 							CancelRight = (ulong)ByondRights.CancelInstall,
@@ -209,7 +230,13 @@ namespace Tgstation.Server.Host.Controllers
 								job,
 								async (core, databaseContextFactory, paramJob, progressHandler, jobCancellationToken) =>
 								{
-									Stream zipFileStream = null;
+									if (sourceRepo != null)
+										await core.ByondManager.EnsureEngineSource(
+											sourceRepo,
+											model.Engine.Value,
+											jobCancellationToken);
+
+									MemoryStream zipFileStream = null;
 									if (fileUploadTicket != null)
 										await using (fileUploadTicket)
 										{
@@ -229,7 +256,7 @@ namespace Tgstation.Server.Host.Controllers
 									await using (zipFileStream)
 										await core.ByondManager.ChangeVersion(
 											progressHandler,
-											version,
+											model,
 											zipFileStream,
 											true,
 											jobCancellationToken);
@@ -260,7 +287,7 @@ namespace Tgstation.Server.Host.Controllers
 		/// <returns>A <see cref="ValueTask{TResult}"/> resulting in the <see cref="IActionResult"/> for the operation.</returns>
 		/// <response code="202">Created <see cref="Job"/> to delete target version successfully.</response>
 		/// <response code="409">Attempted to delete the active BYOND <see cref="Version"/>.</response>
-		/// <response code="410">The <see cref="ByondVersionDeleteRequest.Version"/> specified was not installed.</response>
+		/// <response code="410">The <see cref="Api.Models.Internal.ByondVersion"/> specified was not installed.</response>
 		[HttpDelete]
 		[TgsAuthorize(ByondRights.DeleteInstall)]
 		[ProducesResponseType(typeof(JobResponse), 202)]
@@ -270,22 +297,22 @@ namespace Tgstation.Server.Host.Controllers
 		{
 			ArgumentNullException.ThrowIfNull(model);
 
-			if (model.Version == null
-				|| model.Version.Revision != -1)
+			if (model.Version.Revision != -1)
 				return BadRequest(new ErrorMessageResponse(ErrorCode.ModelValidationFailure));
 
-			var version = NormalizeVersion(model.Version);
+			if (model.Engine == EngineType.Byond)
+				model.Version = NormalizeByondVersion(model.Version);
 
 			var notInstalledResponse = await WithComponentInstance(
 				instance =>
 				{
 					var byondManager = instance.ByondManager;
 
-					if (version == byondManager.ActiveVersion)
+					if (model.Equals(byondManager.ActiveVersion))
 						return ValueTask.FromResult<IActionResult>(
 							Conflict(new ErrorMessageResponse(ErrorCode.ByondCannotDeleteActiveVersion)));
 
-					var versionNotInstalled = !byondManager.InstalledVersions.Any(x => x == version);
+					var versionNotInstalled = !byondManager.InstalledVersions.Any(x => x.Equals(model));
 
 					return ValueTask.FromResult<IActionResult>(
 						versionNotInstalled
@@ -296,22 +323,27 @@ namespace Tgstation.Server.Host.Controllers
 			if (notInstalledResponse != null)
 				return notInstalledResponse;
 
-			var isCustomVersion = version.Build != -1;
+			var isByondVersion = model.Engine.Value == EngineType.Byond;
 
 			// run the install through the job manager
 			var job = new Job
 			{
-				Description = $"Delete installed BYOND version {version}",
+				Description = $"Delete installed {model.Engine.Value} version {model.Version}",
 				StartedBy = AuthenticationContext.User,
 				CancelRightsType = RightsType.Byond,
-				CancelRight = (ulong)(isCustomVersion ? ByondRights.InstallOfficialOrChangeActiveVersion : ByondRights.InstallCustomVersion),
+				CancelRight = (ulong)(
+					isByondVersion
+						? model.Version.Build != -1
+							? ByondRights.InstallOfficialOrChangeActiveByondVersion
+							: ByondRights.InstallCustomByondVersion
+						: ByondRights.InstallCustomOpenDreamVersion | ByondRights.InstallOfficialOrChangeActiveOpenDreamVersion),
 				Instance = Instance,
 			};
 
 			await jobManager.RegisterOperation(
 				job,
 				(instanceCore, databaseContextFactory, job, progressReporter, jobCancellationToken)
-					=> instanceCore.ByondManager.DeleteVersion(progressReporter, version, jobCancellationToken),
+					=> instanceCore.ByondManager.DeleteVersion(progressReporter, model, jobCancellationToken),
 				cancellationToken);
 
 			var apiResponse = job.ToApi();

src/Tgstation.Server.Host/Models/CompileJob.cs

@@ -82,7 +82,7 @@ namespace Tgstation.Server.Host.Models
 		}
 
 		/// <inheritdoc />
-		public CompileJobResponse ToApi() => new CompileJobResponse
+		public CompileJobResponse ToApi() => new ()
 		{
 			DirectoryName = DirectoryName,
 			DmeName = DmeName,
@@ -90,7 +90,9 @@ namespace Tgstation.Server.Host.Models
 			Job = Job.ToApi(),
 			Output = Output,
 			RevisionInformation = RevisionInformation.ToApi(),
-			ByondVersion = Version.Parse(ByondVersion),
+			ByondVersion = Api.Models.Internal.ByondVersion.TryParse(ByondVersion, out var version)
+				? version
+				: throw new InvalidOperationException($"Failed to parse BYOND version: {ByondVersion}"),
 			MinimumSecurityLevel = MinimumSecurityLevel,
 			DMApiVersion = DMApiVersion,
 			RepositoryOrigin = RepositoryOrigin != null ? new Uri(RepositoryOrigin) : null,

tests/Tgstation.Server.Api.Tests/Rights/TestRights.cs

@@ -40,7 +40,7 @@ namespace Tgstation.Server.Api.Rights.Tests
 		[TestMethod]
 		public void TestAllRightsWorks()
 		{
-			var allByondRights = ByondRights.CancelInstall | ByondRights.InstallOfficialOrChangeActiveVersion | ByondRights.ListInstalled | ByondRights.ReadActive | ByondRights.InstallCustomVersion | ByondRights.DeleteInstall;
+			var allByondRights = ByondRights.CancelInstall | ByondRights.InstallOfficialOrChangeActiveByondVersion | ByondRights.ListInstalled | ByondRights.ReadActive | ByondRights.InstallCustomByondVersion | ByondRights.DeleteInstall;
 			var automaticByondRights = RightsHelper.AllRights<ByondRights>();
 
 			Assert.AreEqual(allByondRights, automaticByondRights);

tests/Tgstation.Server.Client.Tests/TestApiClient.cs

@@ -11,6 +11,8 @@ using System.Threading;
 using System.Threading.Tasks;
 
 using Tgstation.Server.Api;
+using Tgstation.Server.Api.Models;
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Api.Models.Response;
 using Tgstation.Server.Common.Http;
 
@@ -22,10 +24,12 @@ namespace Tgstation.Server.Client.Tests
 		[TestMethod]
 		public async Task TestDeserializingByondModelsWork()
 		{
-			var sample = new ByondResponse
-			{
-				Version = new Version(511, 1385, 0)
-			};
+			var sample = new ByondResponse(
+				new ByondVersion
+				{
+					Engine = EngineType.Byond,
+					Version = new Version(511, 1385, 0)
+				});
 
 			var sampleJson = JsonConvert.SerializeObject(sample, new JsonSerializerSettings
 			{
@@ -51,10 +55,12 @@ namespace Tgstation.Server.Client.Tests
 		[TestMethod]
 		public async Task TestUnrecognizedResponse()
 		{
-			var sample = new ByondResponse
-			{
-				Version = new Version(511, 1385)
-			};
+			var sample = new ByondResponse(
+				new ByondVersion
+				{
+					Engine = EngineType.Byond,
+					Version = new Version(511, 1385)
+				});
 
 			var fakeJson = "asdfasd <>F#(*)U*#JLI";
 

tests/Tgstation.Server.Host.Tests/Components/Byond/TestPosixByondInstaller.cs

@@ -6,6 +6,8 @@ using System.IO;
 using System.Linq;
 using System.Threading.Tasks;
 
+using Tgstation.Server.Api.Models;
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Host.IO;
 
 namespace Tgstation.Server.Host.Components.Byond.Tests
@@ -62,7 +64,11 @@ namespace Tgstation.Server.Host.Components.Byond.Tests
 						new MemoryStream(ourArray)))
 				.Verifiable();
 
-			var result = await installer.DownloadVersion(new Version(511, 1385), default);
+			var result = await installer.DownloadVersion(new ByondVersion
+			{
+				Engine = EngineType.Byond,
+				Version = new Version(123, 252345),
+			}, default);
 
 			Assert.IsTrue(ourArray.SequenceEqual(result.ToArray()));
 			mockIOManager.Verify();
@@ -79,9 +85,17 @@ namespace Tgstation.Server.Host.Components.Byond.Tests
 
 			const string FakePath = "fake";
 			await Assert.ThrowsExceptionAsync<ArgumentNullException>(() => installer.InstallByond(null, null, default).AsTask());
-			await Assert.ThrowsExceptionAsync<ArgumentNullException>(() => installer.InstallByond(new Version(123,252345), null, default).AsTask());
 
-			await installer.InstallByond(new Version(511, 1385), FakePath, default);
+			var byondVersion = new ByondVersion
+			{
+				Engine = EngineType.Byond,
+				Version = new Version(123, 252345),
+			};
+
+			await Assert.ThrowsExceptionAsync<ArgumentNullException>(() => installer.InstallByond(byondVersion, null, default).AsTask());
+
+			byondVersion.Version = new Version(511, 1385);
+			await installer.InstallByond(byondVersion, FakePath, default);
 
 			mockPostWriteHandler.Verify(x => x.HandleWrite(It.IsAny<string>()), Times.Exactly(4));
 		}

tests/Tgstation.Server.Host.Tests/Security/TestAuthenticationContext.cs

@@ -1,4 +1,4 @@
-using Microsoft.VisualStudio.TestTools.UnitTesting;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
 using Moq;
 using System;
 
@@ -50,7 +50,7 @@ namespace Tgstation.Server.Host.Security.Tests
 			var authContext = new AuthenticationContext(null, user, instanceUser);
 
 			user.PermissionSet.AdministrationRights = AdministrationRights.WriteUsers;
-			instanceUser.ByondRights = ByondRights.InstallOfficialOrChangeActiveVersion | ByondRights.ReadActive;
+			instanceUser.ByondRights = ByondRights.InstallOfficialOrChangeActiveByondVersion | ByondRights.ReadActive;
 			Assert.AreEqual((ulong)user.PermissionSet.AdministrationRights, authContext.GetRight(RightsType.Administration));
 			Assert.AreEqual((ulong)instanceUser.ByondRights, authContext.GetRight(RightsType.Byond));
 		}

tests/Tgstation.Server.Tests/CachingFileDownloader.cs

@@ -9,6 +9,7 @@ using Microsoft.VisualStudio.TestTools.UnitTesting;
 
 using Moq;
 
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Common.Http;
 using Tgstation.Server.Host.Extensions;
 using Tgstation.Server.Host.IO;
@@ -42,9 +43,9 @@ namespace Tgstation.Server.Tests
 			var logger = loggerFactory.CreateLogger("CachingFileDownloader");
 
 			var cfd = new CachingFileDownloader(loggerFactory.CreateLogger<CachingFileDownloader>());
-			var edgeVersion = await ByondTest.GetEdgeVersion(cfd, cancellationToken);
+			var edgeVersion = await ByondTest.GetEdgeVersion(Api.Models.EngineType.Byond, cfd, cancellationToken);
 
-			await InitializeByondVersion(logger, edgeVersion, new PlatformIdentifier().IsWindows, cancellationToken);
+			await InitializeByondVersion(logger, edgeVersion.Version, new PlatformIdentifier().IsWindows, cancellationToken);
 
 			// predownload the target github release update asset
 			var gitHubToken = Environment.GetEnvironmentVariable("TGS_TEST_GITHUB_TOKEN");
@@ -76,10 +77,16 @@ namespace Tgstation.Server.Tests
 			ServiceCollectionExtensions.UseFileDownloader<CachingFileDownloader>();
 		}
 
-		public static async ValueTask InitializeByondVersion(ILogger logger, Version version, bool windows, CancellationToken cancellationToken)
+		public static async ValueTask InitializeByondVersion(ILogger logger, Version byondVersion, bool windows, CancellationToken cancellationToken)
 		{
+			var version = new ByondVersion
+			{
+				Engine = Api.Models.EngineType.Byond,
+				Version = byondVersion,
+			};
+
 			var url = new Uri(
-				$"https://www.byond.com/download/build/{version.Major}/{version.Major}.{version.Minor}_byond{(!windows ? "_linux" : string.Empty)}.zip");
+				$"https://www.byond.com/download/build/{version.Version.Major}/{version.Version.Major}.{version.Version.Minor}_byond{(!windows ? "_linux" : string.Empty)}.zip");
 			string path = null;
 			if (TestingUtils.RunningInGitHubActions)
 			{
@@ -91,7 +98,7 @@ namespace Tgstation.Server.Tests
 					windows ? "windows" : "linux");
 				path = Path.Combine(
 					dir,
-					$"{version.Major}.{version.Minor}.zip");
+					$"{version.Version.Major}.{version.Version.Minor}.zip");
 			}
 
 			await (await CacheFile(logger, url, null, path, cancellationToken)).DisposeAsync();

tests/Tgstation.Server.Tests/Live/DummyChatProvider.cs

@@ -12,6 +12,7 @@ using Moq;
 
 using Newtonsoft.Json;
 
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Host.Components.Chat;
 using Tgstation.Server.Host.Components.Chat.Commands;
 using Tgstation.Server.Host.Components.Chat.Providers;
@@ -100,7 +101,15 @@ namespace Tgstation.Server.Tests.Live
 			return ValueTask.CompletedTask;
 		}
 
-		public override ValueTask<Func<string, string, ValueTask<Func<bool, ValueTask>>>> SendUpdateMessage(RevisionInformation revisionInformation, Version byondVersion, DateTimeOffset? estimatedCompletionTime, string gitHubOwner, string gitHubRepo, ulong channelId, bool localCommitPushed, CancellationToken cancellationToken)
+		public override ValueTask<Func<string, string, ValueTask<Func<bool, ValueTask>>>> SendUpdateMessage(
+			Host.Models.RevisionInformation revisionInformation,
+			ByondVersion byondVersion,
+			DateTimeOffset? estimatedCompletionTime,
+			string gitHubOwner,
+			string gitHubRepo,
+			ulong channelId,
+			bool localCommitPushed,
+			CancellationToken cancellationToken)
 		{
 			ArgumentNullException.ThrowIfNull(revisionInformation);
 			ArgumentNullException.ThrowIfNull(byondVersion);

tests/Tgstation.Server.Tests/Live/Instance/ByondTest.cs

@@ -6,13 +6,17 @@ using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 
+using Elasticsearch.Net.Specification.IndexLifecycleManagementApi;
+
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
+using Microsoft.VisualStudio.TestPlatform.CrossPlatEngine;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 
 using Moq;
 
 using Tgstation.Server.Api.Models;
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Api.Models.Request;
 using Tgstation.Server.Api.Models.Response;
 using Tgstation.Server.Client;
@@ -32,16 +36,22 @@ namespace Tgstation.Server.Tests.Live.Instance
 
 		readonly Api.Models.Instance metadata;
 
-		static Version edgeVersion;
+		static Dictionary<EngineType, ByondVersion> edgeVersions = new Dictionary<EngineType, ByondVersion>
+		{
+			{ EngineType.Byond, null },
+			{ EngineType.OpenDream, null }
+		};
 
-		Version testVersion;
+		ByondVersion testVersion;
+		EngineType testEngine;
 
-		public ByondTest(IByondClient byondClient, IJobsClient jobsClient, IFileDownloader fileDownloader, Api.Models.Instance metadata)
+		public ByondTest(IByondClient byondClient, IJobsClient jobsClient, IFileDownloader fileDownloader, Api.Models.Instance metadata, EngineType engineType)
 			: base(jobsClient)
 		{
 			this.byondClient = byondClient ?? throw new ArgumentNullException(nameof(byondClient));
 			this.fileDownloader = fileDownloader ?? throw new ArgumentNullException(nameof(fileDownloader));
 			this.metadata = metadata ?? throw new ArgumentNullException(nameof(metadata));
+			this.testEngine = engineType;
 		}
 
 		public Task Run(CancellationToken cancellationToken, out Task firstInstall)
@@ -50,42 +60,67 @@ namespace Tgstation.Server.Tests.Live.Instance
 			return RunContinued(firstInstall, cancellationToken);
 		}
 
-		public static async Task<Version> GetEdgeVersion(IFileDownloader fileDownloader, CancellationToken cancellationToken)
+		public static async ValueTask<ByondVersion> GetEdgeVersion(EngineType engineType, IFileDownloader fileDownloader, CancellationToken cancellationToken)
 		{
+			var edgeVersion = edgeVersions[engineType];
+
 			if (edgeVersion != null)
 				return edgeVersion;
 
-			await using var provider = fileDownloader.DownloadFile(new Uri("https://www.byond.com/download/version.txt"), null);
-			var stream = await provider.GetResult(cancellationToken);
-			using var reader = new StreamReader(stream, Encoding.UTF8, false, -1, true);
-			var text = await reader.ReadToEndAsync();
-			var splits = text.Split('\n', StringSplitOptions.TrimEntries | StringSplitOptions.RemoveEmptyEntries);
+			ByondVersion byondVersion;
+			if (engineType == EngineType.Byond)
+			{
+				await using var provider = fileDownloader.DownloadFile(new Uri("https://www.byond.com/download/version.txt"), null);
+				var stream = await provider.GetResult(cancellationToken);
+				using var reader = new StreamReader(stream, Encoding.UTF8, false, -1, true);
+				var text = await reader.ReadToEndAsync(cancellationToken);
+				var splits = text.Split('\n', StringSplitOptions.TrimEntries | StringSplitOptions.RemoveEmptyEntries);
 
-			var targetVersion = splits.Last();
+				var targetVersion = splits.Last();
 
-			var missingVersionMap = new PlatformIdentifier().IsWindows
-				? new Dictionary<string, string>()
-				{
-				}
-				// linux map also needs updating in CI
-				: new Dictionary<string, string>()
-				{
+				var missingVersionMap = new PlatformIdentifier().IsWindows
+					? new Dictionary<string, string>()
+					{
+					}
+					// linux map also needs updating in CI
+					: new Dictionary<string, string>()
+					{
 					{ "515.1612", "515.1611" }
-				};
+					};
 
-			if (missingVersionMap.TryGetValue(targetVersion, out var remappedVersion))
-				targetVersion = remappedVersion;
+				if (missingVersionMap.TryGetValue(targetVersion, out var remappedVersion))
+					targetVersion = remappedVersion;
 
-			return edgeVersion = Version.Parse(targetVersion);
+				Assert.IsTrue(ByondVersion.TryParse(targetVersion, out byondVersion), $"Bad version: {targetVersion}");
+			}
+			else
+			{
+				Assert.Fail($"Edge version retrieval for {engineType} not implemented!");
+				return null;
+			}
+
+			return edgeVersions[engineType] = byondVersion;
 		}
 
 		async Task RunPartOne(CancellationToken cancellationToken)
 		{
-			testVersion = await GetEdgeVersion(fileDownloader, cancellationToken);
+			testVersion = await GetEdgeVersion(EngineType.Byond, fileDownloader, cancellationToken);
 			await TestNoVersion(cancellationToken);
+			await TestInstallNullVersion(cancellationToken);
 			await TestInstallStable(cancellationToken);
 		}
 
+		ValueTask TestInstallNullVersion(CancellationToken cancellationToken)
+			=> ApiAssert.ThrowsException<ApiConflictException, ByondInstallResponse>(
+				() => byondClient.SetActiveVersion(
+					new ByondVersionRequest
+					{
+						Engine = testEngine,
+					},
+					null,
+					cancellationToken),
+				ErrorCode.ModelValidationFailure);
+
 		async Task RunContinued(Task firstInstall, CancellationToken cancellationToken)
 		{
 			await firstInstall;
@@ -98,7 +133,8 @@ namespace Tgstation.Server.Tests.Live.Instance
 		{
 			var deleteThisOneBecauseItWasntPartOfTheOriginalTest = await byondClient.DeleteVersion(new ByondVersionDeleteRequest
 			{
-				Version = new(testVersion.Major, testVersion.Minor, 2)
+				Engine = testEngine,
+				Version = new(testVersion.Version.Major, testVersion.Version.Minor, 2)
 			}, cancellationToken);
 			await WaitForJob(deleteThisOneBecauseItWasntPartOfTheOriginalTest, 30, false, null, cancellationToken);
 
@@ -112,14 +148,18 @@ namespace Tgstation.Server.Tests.Live.Instance
 			var uninstallResponseTask = byondClient.DeleteVersion(
 				new ByondVersionDeleteRequest
 				{
-					Version = testVersion
+					Version = testVersion.Version,
+					Engine = testVersion.Engine,
+					SourceCommittish = testVersion.SourceCommittish,
 				},
 				cancellationToken);
 
 			var badBecauseActiveResponseTask = ApiAssert.ThrowsException<ConflictException, JobResponse>(() => byondClient.DeleteVersion(
 				new ByondVersionDeleteRequest
 				{
-					Version = new(testVersion.Major, testVersion.Minor, 1)
+					Version = new(testVersion.Version.Major, testVersion.Version.Minor, 1),
+					Engine = testVersion.Engine,
+					SourceCommittish = testVersion.SourceCommittish,
 				},
 				cancellationToken), ErrorCode.ByondCannotDeleteActiveVersion);
 
@@ -140,7 +180,7 @@ namespace Tgstation.Server.Tests.Live.Instance
 			var newVersions = await byondClient.InstalledVersions(null, cancellationToken);
 			Assert.IsNotNull(newVersions);
 			Assert.AreEqual(1, newVersions.Count);
-			Assert.AreEqual(new Version(testVersion.Major, testVersion.Minor, 1), newVersions[0].Version);
+			Assert.AreEqual(new Version(testVersion.Version.Major, testVersion.Version.Minor, 1), newVersions[0].Version);
 		}
 
 		async Task TestInstallFakeVersion(CancellationToken cancellationToken)
@@ -158,7 +198,9 @@ namespace Tgstation.Server.Tests.Live.Instance
 		{
 			var newModel = new ByondVersionRequest
 			{
-				Version = testVersion
+				Version = testVersion.Version,
+				Engine = testVersion.Engine,
+				SourceCommittish = testVersion.SourceCommittish,
 			};
 			var test = await byondClient.SetActiveVersion(newModel, null, cancellationToken);
 			Assert.IsNotNull(test.InstallJob);
@@ -220,7 +262,9 @@ namespace Tgstation.Server.Tests.Live.Instance
 			var test = await byondClient.SetActiveVersion(
 				new ByondVersionRequest
 				{
-					Version = testVersion,
+					Engine = testVersion.Engine,
+					Version = testVersion.Version,
+					SourceCommittish = testVersion.SourceCommittish,
 					UploadCustomZip = true
 				},
 				stableBytesMs,
@@ -234,7 +278,9 @@ namespace Tgstation.Server.Tests.Live.Instance
 			var test2 = await byondClient.SetActiveVersion(
 				new ByondVersionRequest
 				{
-					Version = testVersion,
+					Version = testVersion.Version,
+					SourceCommittish = testVersion.SourceCommittish,
+					Engine = testVersion.Engine,
 					UploadCustomZip = true
 				},
 				stableBytesMs,
@@ -244,22 +290,24 @@ namespace Tgstation.Server.Tests.Live.Instance
 			await WaitForJob(test2.InstallJob, 30, false, null, cancellationToken);
 
 			var newSettings = await byondClient.ActiveVersion(cancellationToken);
-			Assert.AreEqual(new Version(testVersion.Major, testVersion.Minor, 2), newSettings.Version);
+			Assert.AreEqual(new Version(testVersion.Version.Major, testVersion.Version.Minor, 2), newSettings.Version);
 
 			// test a few switches
 			var installResponse = await byondClient.SetActiveVersion(new ByondVersionRequest
 			{
-				Version = testVersion
+				Version = testVersion.Version,
+				SourceCommittish = testVersion.SourceCommittish,
+				Engine = testVersion.Engine,
 			}, null, cancellationToken);
 			Assert.IsNull(installResponse.InstallJob);
 			await ApiAssert.ThrowsException<ApiConflictException, ByondInstallResponse>(() => byondClient.SetActiveVersion(new ByondVersionRequest
 			{
-				Version = new Version(testVersion.Major, testVersion.Minor, 3)
+				Version = new Version(testVersion.Version.Major, testVersion.Version.Minor, 3)
 			}, null, cancellationToken), ErrorCode.ByondNonExistentCustomVersion);
 
 			installResponse = await byondClient.SetActiveVersion(new ByondVersionRequest
 			{
-				Version = new Version(testVersion.Major, testVersion.Minor, 1)
+				Version = new Version(testVersion.Version.Major, testVersion.Version.Minor, 1)
 			}, null, cancellationToken);
 			Assert.IsNull(installResponse.InstallJob);
 		}

tests/Tgstation.Server.Tests/Live/Instance/InstanceTest.cs

@@ -10,6 +10,7 @@ using Microsoft.Extensions.Options;
 using Moq;
 
 using Tgstation.Server.Api.Models;
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Api.Models.Request;
 using Tgstation.Server.Api.Models.Response;
 using Tgstation.Server.Client;
@@ -43,9 +44,10 @@ namespace Tgstation.Server.Tests.Live.Instance
 			ushort ddPort,
 			bool highPrioDD,
 			bool lowPrioDeployment,
+			EngineType engineType,
 			CancellationToken cancellationToken)
 		{
-			var byondTest = new ByondTest(instanceClient.Byond, instanceClient.Jobs, fileDownloader, instanceClient.Metadata);
+			var byondTest = new ByondTest(instanceClient.Byond, instanceClient.Jobs, fileDownloader, instanceClient.Metadata, engineType);
 			var chatTest = new ChatTest(instanceClient.ChatBots, instanceManagerClient, instanceClient.Jobs, instanceClient.Metadata);
 			var configTest = new ConfigurationTest(instanceClient.Configuration, instanceClient.Metadata);
 			var repoTest = new RepositoryTest(instanceClient.Repository, instanceClient.Jobs);
@@ -66,17 +68,23 @@ namespace Tgstation.Server.Tests.Live.Instance
 			await byondTask;
 
 			await new WatchdogTest(
-				await ByondTest.GetEdgeVersion(fileDownloader, cancellationToken), instanceClient, instanceManager, serverPort, highPrioDD, ddPort).Run(cancellationToken);
+				await ByondTest.GetEdgeVersion(engineType, fileDownloader, cancellationToken), instanceClient, instanceManager, serverPort, highPrioDD, ddPort).Run(cancellationToken);
 		}
 
 		public async Task RunCompatTests(
-			Version compatVersion,
+			Version compatByondVersion,
 			IInstanceClient instanceClient,
 			ushort dmPort,
 			ushort ddPort,
 			bool highPrioDD,
 			CancellationToken cancellationToken)
 		{
+			var compatVersion = new ByondVersion
+			{
+				Engine = EngineType.Byond,
+				Version = compatByondVersion,
+			};
+
 			System.Console.WriteLine($"COMPAT TEST START: {compatVersion}");
 			const string Origin = "https://github.com/Cyberboss/common_core";
 			var cloneRequest = instanceClient.Repository.Clone(new RepositoryCreateRequest
@@ -155,7 +163,9 @@ namespace Tgstation.Server.Tests.Live.Instance
 				installJob2 = await instanceClient.Byond.SetActiveVersion(new ByondVersionRequest
 				{
 					UploadCustomZip = true,
-					Version = compatVersion,
+					Version = compatVersion.Version,
+					Engine = compatVersion.Engine,
+					SourceCommittish = compatVersion.SourceCommittish
 				}, stableBytesMs, cancellationToken);
 			}
 

tests/Tgstation.Server.Tests/Live/Instance/WatchdogTest.cs

@@ -18,6 +18,7 @@ using System.Threading;
 using System.Threading.Tasks;
 
 using Tgstation.Server.Api.Models;
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Api.Models.Request;
 using Tgstation.Server.Api.Models.Response;
 using Tgstation.Server.Client;
@@ -57,11 +58,11 @@ namespace Tgstation.Server.Tests.Live.Instance
 		readonly ushort ddPort;
 		readonly bool highPrioDD;
 		readonly TopicClient topicClient;
-		readonly Version testVersion;
+		readonly ByondVersion testVersion;
 
 		bool ranTimeoutTest = false;
 
-		public WatchdogTest(Version testVersion, IInstanceClient instanceClient, InstanceManager instanceManager, ushort serverPort, bool highPrioDD, ushort ddPort)
+		public WatchdogTest(ByondVersion testVersion, IInstanceClient instanceClient, InstanceManager instanceManager, ushort serverPort, bool highPrioDD, ushort ddPort)
 			: base(instanceClient.Jobs)
 		{
 			this.instanceClient = instanceClient ?? throw new ArgumentNullException(nameof(instanceClient));
@@ -94,8 +95,9 @@ namespace Tgstation.Server.Tests.Live.Instance
 				var byondVersion = list[0];
 
 				Assert.AreEqual(1, byondVersion.Version.Build);
-				Assert.AreEqual(testVersion.Major, byondVersion.Version.Major);
-				Assert.AreEqual(testVersion.Minor, byondVersion.Version.Minor);
+				Assert.AreEqual(testVersion.Version.Major, byondVersion.Version.Major);
+				Assert.AreEqual(testVersion.Version.Minor, byondVersion.Version.Minor);
+				Assert.AreEqual(testVersion.Engine, byondVersion.Engine);
 			}
 
 			await Task.WhenAll(
@@ -230,10 +232,10 @@ namespace Tgstation.Server.Tests.Live.Instance
 
 		async Task<JobResponse> TestDeleteByondInstallErrorCasesAndQueing(CancellationToken cancellationToken)
 		{
-			var testCustomVersion = new Version(testVersion.Major, testVersion.Minor, 1);
+			var testCustomVersion = new Version(testVersion.Version.Major, testVersion.Version.Minor, 1);
 			var currentByond = await instanceClient.Byond.ActiveVersion(cancellationToken);
 			Assert.IsNotNull(currentByond);
-			Assert.AreEqual(testVersion.Semver(), currentByond.Version);
+			Assert.AreEqual(testVersion.Version.Semver(), currentByond.Version);
 
 			// Change the active version and check we get delayed while deleting the old one because the watchdog is using it
 			var setActiveResponse = await instanceClient.Byond.SetActiveVersion(
@@ -250,7 +252,8 @@ namespace Tgstation.Server.Tests.Live.Instance
 			var deleteJob = await instanceClient.Byond.DeleteVersion(
 				new ByondVersionDeleteRequest
 				{
-					Version = testVersion,
+					Version = testVersion.Version,
+					SourceCommittish = testVersion.SourceCommittish,
 				},
 				cancellationToken);
 
@@ -265,7 +268,9 @@ namespace Tgstation.Server.Tests.Live.Instance
 			setActiveResponse = await instanceClient.Byond.SetActiveVersion(
 				new ByondVersionRequest
 				{
-					Version = testVersion,
+					Version = testVersion.Version,
+					Engine = testVersion.Engine,
+					SourceCommittish = testVersion.SourceCommittish
 				},
 				null,
 				cancellationToken);
@@ -291,7 +296,9 @@ namespace Tgstation.Server.Tests.Live.Instance
 			deleteJob = await instanceClient.Byond.DeleteVersion(
 				new ByondVersionDeleteRequest
 				{
-					Version = testVersion,
+					Version = testVersion.Version,
+					Engine = testVersion.Engine,
+					SourceCommittish = testVersion.SourceCommittish,
 				},
 				cancellationToken);
 
@@ -954,9 +961,8 @@ namespace Tgstation.Server.Tests.Live.Instance
 			System.Console.WriteLine("TEST: WATCHDOG BYOND VERSION UPDATE TEST");
 			var versionToInstall = testVersion;
 
-			versionToInstall = versionToInstall.Semver();
 			var currentByondVersion = await instanceClient.Byond.ActiveVersion(cancellationToken);
-			Assert.AreNotEqual(versionToInstall, currentByondVersion.Version);
+			Assert.AreNotEqual(versionToInstall, currentByondVersion);
 
 			var initialStatus = await instanceClient.DreamDaemon.Read(cancellationToken);
 
@@ -969,7 +975,9 @@ namespace Tgstation.Server.Tests.Live.Instance
 			var byondInstallJobTask = instanceClient.Byond.SetActiveVersion(
 				new ByondVersionRequest
 				{
-					Version = versionToInstall
+					Version = versionToInstall.Version,
+					Engine = versionToInstall.Engine,
+					SourceCommittish = versionToInstall.SourceCommittish,
 				},
 				null,
 				cancellationToken);

tests/Tgstation.Server.Tests/Live/TestLiveServer.cs

@@ -28,6 +28,7 @@ using Npgsql;
 
 using Tgstation.Server.Api;
 using Tgstation.Server.Api.Models;
+using Tgstation.Server.Api.Models.Internal;
 using Tgstation.Server.Api.Models.Request;
 using Tgstation.Server.Api.Models.Response;
 using Tgstation.Server.Api.Rights;
@@ -955,7 +956,12 @@ namespace Tgstation.Server.Tests.Live
 		}
 
 		[TestMethod]
-		public async Task TestStandardTgsOperation()
+		public Task TestStandardTgsOperation() => TestStandardTgsOperation(EngineType.Byond);
+
+		[TestMethod]
+		public Task TestOpenDreamTgsOperation() => TestStandardTgsOperation(EngineType.OpenDream);
+
+		async Task TestStandardTgsOperation(EngineType engineType)
 		{
 			using(var currentProcess = System.Diagnostics.Process.GetCurrentProcess())
 			{
@@ -980,7 +986,7 @@ namespace Tgstation.Server.Tests.Live
 			ServiceCollectionExtensions.UseAdditionalLoggerProvider<HardFailLoggerProvider>();
 
 			var failureTask = HardFailLoggerProvider.FailureSource;
-			var internalTask = TestTgsInternal(hardCancellationToken);
+			var internalTask = TestTgsInternal(engineType, hardCancellationToken);
 			await Task.WhenAny(
 				internalTask,
 				failureTask);
@@ -1012,7 +1018,7 @@ namespace Tgstation.Server.Tests.Live
 				await internalTask;
 		}
 
-		async Task TestTgsInternal(CancellationToken hardCancellationToken)
+		async Task TestTgsInternal(EngineType engineType, CancellationToken hardCancellationToken)
 		{
 			var discordConnectionString = Environment.GetEnvironmentVariable("TGS_TEST_DISCORD_TOKEN");
 			var ircConnectionString = Environment.GetEnvironmentVariable("TGS_TEST_IRC_CONNECTION_STRING");
@@ -1118,7 +1124,7 @@ namespace Tgstation.Server.Tests.Live
 					async Task RunInstanceTests()
 					{
 						// Some earlier linux BYOND versions have a critical bug where replacing the directory in non-basic watchdogs causes the DreamDaemon cwd to change
-						var canRunCompatTests = new PlatformIdentifier().IsWindows;
+						var canRunCompatTests = engineType == EngineType.Byond && new PlatformIdentifier().IsWindows;
 						var compatTests = canRunCompatTests
 							? FailFast(
 								instanceTest
@@ -1142,6 +1148,7 @@ namespace Tgstation.Server.Tests.Live
 									mainDDPort,
 									server.HighPriorityDreamDaemon,
 									server.LowPriorityDeployments,
+									engineType,
 									cancellationToken));
 
 						await compatTests;
@@ -1308,7 +1315,7 @@ namespace Tgstation.Server.Tests.Live
 				preStartupTime = DateTimeOffset.UtcNow;
 				serverTask = server.Run(cancellationToken).AsTask();
 				long expectedCompileJobId, expectedStaged;
-				var edgeByond = await ByondTest.GetEdgeVersion(fileDownloader, cancellationToken);
+				var edgeVersion = await ByondTest.GetEdgeVersion(engineType, fileDownloader, cancellationToken);
 				using (var adminClient = await CreateAdminClient(server.Url, cancellationToken))
 				{
 					var instanceClient = adminClient.Instances.CreateClient(instance);
@@ -1319,7 +1326,7 @@ namespace Tgstation.Server.Tests.Live
 					Assert.AreEqual(WatchdogStatus.Online, dd.Status.Value);
 
 					var compileJob = await instanceClient.DreamMaker.Compile(cancellationToken);
-					var wdt = new WatchdogTest(edgeByond, instanceClient, GetInstanceManager(), (ushort)server.Url.Port, server.HighPriorityDreamDaemon, mainDDPort);
+					var wdt = new WatchdogTest(edgeVersion, instanceClient, GetInstanceManager(), (ushort)server.Url.Port, server.HighPriorityDreamDaemon, mainDDPort);
 					await wdt.WaitForJob(compileJob, 30, false, null, cancellationToken);
 
 					dd = await instanceClient.DreamDaemon.Read(cancellationToken);
@@ -1366,7 +1373,7 @@ namespace Tgstation.Server.Tests.Live
 					Assert.AreEqual(WatchdogStatus.Online, currentDD.Status);
 					Assert.AreEqual(expectedStaged, currentDD.StagedCompileJob.Job.Id.Value);
 
-					var wdt = new WatchdogTest(edgeByond, instanceClient, GetInstanceManager(), (ushort)server.Url.Port, server.HighPriorityDreamDaemon, mainDDPort);
+					var wdt = new WatchdogTest(edgeVersion, instanceClient, GetInstanceManager(), (ushort)server.Url.Port, server.HighPriorityDreamDaemon, mainDDPort);
 					currentDD = await wdt.TellWorldToReboot(cancellationToken);
 					Assert.AreEqual(expectedStaged, currentDD.ActiveCompileJob.Job.Id.Value);
 					Assert.IsNull(currentDD.StagedCompileJob);

tests/Tgstation.Server.Tests/TestDatabase.cs

@@ -134,7 +134,7 @@ namespace Tgstation.Server.Tests
 				{
 					new Host.Models.InstancePermissionSet
 					{
-						ByondRights = ByondRights.InstallCustomVersion,
+						ByondRights = ByondRights.InstallCustomByondVersion,
 						ChatBotRights = ChatBotRights.None,
 						ConfigurationRights = ConfigurationRights.Read,
 						DreamDaemonRights = DreamDaemonRights.ReadRevision,

tests/Tgstation.Server.Tests/TestVersions.cs

@@ -28,6 +28,8 @@ using Tgstation.Server.Host.Database;
 using Tgstation.Server.Host.IO;
 using Tgstation.Server.Host.System;
 using System.Net;
+using Tgstation.Server.Api.Models.Internal;
+using Tgstation.Server.Api.Models;
 
 namespace Tgstation.Server.Tests
 {
@@ -125,12 +127,18 @@ namespace Tgstation.Server.Tests
 
 			const string ArchiveEntryPath = "byond/bin/dd.exe";
 			var hasEntry = ArchiveHasFileEntry(
-				await byondInstaller.DownloadVersion(WindowsByondInstaller.DDExeVersion, default),
+				await byondInstaller.DownloadVersion(
+					new ByondVersion
+					{
+						Engine = EngineType.Byond,
+						Version = WindowsByondInstaller.DDExeVersion
+					},
+					default),
 				ArchiveEntryPath);
 
 			Assert.IsTrue(hasEntry);
 
-			var (byondBytes, version) = await GetByondVersionPriorTo(byondInstaller, WindowsByondInstaller.DDExeVersion);
+			var (byondBytes, _) = await GetByondVersionPriorTo(byondInstaller, WindowsByondInstaller.DDExeVersion);
 			hasEntry = ArchiveHasFileEntry(
 				byondBytes,
 				ArchiveEntryPath);
@@ -203,8 +211,18 @@ namespace Tgstation.Server.Tests
 			try
 			{
 				await TestMapThreadsVersion(
-					ByondInstallerBase.MapThreadsVersion,
-					await byondInstaller.DownloadVersion(ByondInstallerBase.MapThreadsVersion, default),
+					new ByondVersion
+					{
+						Engine = EngineType.Byond,
+						Version = ByondInstallerBase.MapThreadsVersion,
+					},
+					await byondInstaller.DownloadVersion(
+						new ByondVersion
+						{
+							Engine = EngineType.Byond,
+							Version = ByondInstallerBase.MapThreadsVersion
+						},
+						default),
 					byondInstaller,
 					ioManager,
 					processExecutor,
@@ -380,22 +398,32 @@ namespace Tgstation.Server.Tests
 			Assert.AreEqual(latestMigrationSL, DatabaseContext.SLLatestMigration);
 		}
 
-		static async Task<Tuple<MemoryStream, Version>> GetByondVersionPriorTo(IByondInstaller byondInstaller, Version version)
+		static async Task<Tuple<MemoryStream, ByondVersion>> GetByondVersionPriorTo(IByondInstaller byondInstaller, Version version)
 		{
 			var minusOneMinor = new Version(version.Major, version.Minor - 1);
+			var byondVersion = new ByondVersion
+			{
+				Engine = EngineType.Byond,
+				Version = minusOneMinor
+			};
 			try
 			{
-				return Tuple.Create(await byondInstaller.DownloadVersion(minusOneMinor, default), minusOneMinor);
+				return Tuple.Create(await byondInstaller.DownloadVersion(
+					byondVersion,
+					CancellationToken.None), byondVersion);
 			}
 			catch (HttpRequestException)
 			{
 				var minusOneMajor = new Version(minusOneMinor.Major - 1, minusOneMinor.Minor);
-				return Tuple.Create(await byondInstaller.DownloadVersion(minusOneMajor, default), minusOneMajor);
+				byondVersion.Version = minusOneMajor;
+				return Tuple.Create(await byondInstaller.DownloadVersion(
+					byondVersion,
+					CancellationToken.None), byondVersion);
 			}
 		}
 
 		static async Task TestMapThreadsVersion(
-			Version byondVersion,
+			ByondVersion byondVersion,
 			Stream byondBytes,
 			IByondInstaller byondInstaller,
 			IIOManager ioManager,