diff --git a/src/Tgstation.Server.Host/Components/Deployment/Remote/GitHubRemoteDeploymentManager.cs b/src/Tgstation.Server.Host/Components/Deployment/Remote/GitHubRemoteDeploymentManager.cs
index a31780bf21..751bb33646 100644
--- a/src/Tgstation.Server.Host/Components/Deployment/Remote/GitHubRemoteDeploymentManager.cs
+++ b/src/Tgstation.Server.Host/Components/Deployment/Remote/GitHubRemoteDeploymentManager.cs
@@ -198,7 +198,7 @@ namespace Tgstation.Server.Host.Components.Deployment.Remote
 					return;
 
 				// We don't just assume, actually check the repo contains the merge commit.
-				if (await repository.ShaIsParent(pr.MergeCommitSha, cancellationToken))
+				if (await repository.CommittishIsParent(pr.MergeCommitSha, cancellationToken))
 				{
 					if (lastMerged == null || lastMerged.MergedAt < pr.MergedAt)
 						lastMerged = pr;
diff --git a/src/Tgstation.Server.Host/Components/Deployment/Remote/GitLabRemoteDeploymentManager.cs b/src/Tgstation.Server.Host/Components/Deployment/Remote/GitLabRemoteDeploymentManager.cs
index 3154b2ee03..2686764cca 100644
--- a/src/Tgstation.Server.Host/Components/Deployment/Remote/GitLabRemoteDeploymentManager.cs
+++ b/src/Tgstation.Server.Host/Components/Deployment/Remote/GitLabRemoteDeploymentManager.cs
@@ -83,7 +83,7 @@ namespace Tgstation.Server.Host.Components.Deployment.Remote
 					return;
 
 				// We don't just assume, actually check the repo contains the merge commit.
-				if (await repository.ShaIsParent(mergeRequest.MergeCommitSha, cancellationToken))
+				if (await repository.CommittishIsParent(mergeRequest.MergeCommitSha, cancellationToken))
 				{
 					if (lastMerged == null || lastMerged.ClosedAt < mergeRequest.ClosedAt)
 						lastMerged = mergeRequest;
diff --git a/src/Tgstation.Server.Host/Components/Engine/OpenDreamInstaller.cs b/src/Tgstation.Server.Host/Components/Engine/OpenDreamInstaller.cs
index e279f0d0cc..ceb95a810f 100644
--- a/src/Tgstation.Server.Host/Components/Engine/OpenDreamInstaller.cs
+++ b/src/Tgstation.Server.Host/Components/Engine/OpenDreamInstaller.cs
@@ -152,7 +152,7 @@ namespace Tgstation.Server.Host.Components.Engine
 					progressSection2,
 					cancellationToken);
 
-				if (!await repo.ShaIsParent("fab769776dada6b9bcad546094d78c604049e0e9", cancellationToken))
+				if (!await repo.CommittishIsParent("fab769776dada6b9bcad546094d78c604049e0e9", cancellationToken))
 					throw new JobException(ErrorCode.OpenDreamTooOld);
 
 				return new RepositoryEngineInstallationData(IOManager, repo, InstallationSourceSubDirectory);
diff --git a/src/Tgstation.Server.Host/Components/Repository/IRepository.cs b/src/Tgstation.Server.Host/Components/Repository/IRepository.cs
index 33c4b9a97c..0482eaaa90 100644
--- a/src/Tgstation.Server.Host/Components/Repository/IRepository.cs
+++ b/src/Tgstation.Server.Host/Components/Repository/IRepository.cs
@@ -170,13 +170,13 @@ namespace Tgstation.Server.Host.Components.Repository
 		ValueTask CopyTo(string path, CancellationToken cancellationToken);
 
 		/// <summary>
-		/// Check if a given <paramref name="sha"/> is a parent of the current <see cref="Head"/>.
+		/// Check if a given <paramref name="committish"/> is a parent of the current <see cref="Head"/>.
 		/// </summary>
-		/// <param name="sha">The SHA to check.</param>
+		/// <param name="committish">The committish of the SHA to check.</param>
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation.</param>
-		/// <returns>A <see cref="Task{TResult}"/> resulting in <see langword="true"/> if <paramref name="sha"/> is a parent of <see cref="Head"/>, <see langword="false"/> otherwise.</returns>
+		/// <returns>A <see cref="Task{TResult}"/> resulting in <see langword="true"/> if <paramref name="committish"/> is a parent of <see cref="Head"/>, <see langword="false"/> otherwise.</returns>
 		/// <remarks>This function is NOT reentrant.</remarks>
-		Task<bool> ShaIsParent(string sha, CancellationToken cancellationToken);
+		Task<bool> CommittishIsParent(string committish, CancellationToken cancellationToken);
 
 		/// <summary>
 		/// Get the tracked reference's current SHA.
diff --git a/src/Tgstation.Server.Host/Components/Repository/Repository.cs b/src/Tgstation.Server.Host/Components/Repository/Repository.cs
index 5f3602675e..cae1677f60 100644
--- a/src/Tgstation.Server.Host/Components/Repository/Repository.cs
+++ b/src/Tgstation.Server.Host/Components/Repository/Repository.cs
@@ -791,16 +791,34 @@ namespace Tgstation.Server.Host.Components.Repository
 			TaskScheduler.Current);
 
 		/// <inheritdoc />
-		public Task<bool> ShaIsParent(string sha, CancellationToken cancellationToken) => Task.Factory.StartNew(
+		public Task<bool> CommittishIsParent(string committish, CancellationToken cancellationToken) => Task.Factory.StartNew(
 			() =>
 			{
-				var targetCommit = libGitRepo.Lookup<Commit>(sha);
-				if (targetCommit == null)
+				var targetObject = libGitRepo.Lookup(committish);
+				if (targetObject == null)
 				{
-					logger.LogTrace("Commit {sha} not found in repository", sha);
+					logger.LogTrace("Committish {committish} not found in repository", committish);
 					return false;
 				}
 
+				if (targetObject is not Commit targetCommit)
+				{
+					if (targetObject is not TagAnnotation)
+					{
+						logger.LogTrace("Committish {committish} is a {type} and does not point to a commit!", committish, targetObject.GetType().Name);
+						return false;
+					}
+
+					targetCommit = targetObject.Peel<Commit>();
+					if (targetCommit == null)
+					{
+						logger.LogError(
+							"TagAnnotation {committish} was found but the commit associated with it could not be found in repository!",
+							committish);
+						return false;
+					}
+				}
+
 				cancellationToken.ThrowIfCancellationRequested();
 				var startSha = Head;
 				var mergeResult = libGitRepo.Merge(
diff --git a/tests/Tgstation.Server.Host.Tests/Components/Engine/TestOpenDreamInstaller.cs b/tests/Tgstation.Server.Host.Tests/Components/Engine/TestOpenDreamInstaller.cs
index 6330ef1b10..6b8024ddac 100644
--- a/tests/Tgstation.Server.Host.Tests/Components/Engine/TestOpenDreamInstaller.cs
+++ b/tests/Tgstation.Server.Host.Tests/Components/Engine/TestOpenDreamInstaller.cs
@@ -40,7 +40,7 @@ namespace Tgstation.Server.Host.Components.Engine.Tests
 
 			var cloneAttempts = 0;
 			var mockRepository = new Mock<IRepository>();
-			mockRepository.Setup(x => x.ShaIsParent(It.IsNotNull<string>(), It.IsAny<CancellationToken>())).ReturnsAsync(true);
+			mockRepository.Setup(x => x.CommittishIsParent(It.IsNotNull<string>(), It.IsAny<CancellationToken>())).ReturnsAsync(true);
 			var mockRepositoryManager = new Mock<IRepositoryManager>();
 			mockRepositoryManager.Setup(x => x.CloneRepository(
 				generalConfig.OpenDreamGitUrl,
diff --git a/tests/Tgstation.Server.Tests/TestRepository.cs b/tests/Tgstation.Server.Tests/TestRepository.cs
index e03fbe984a..8a16f0ddd9 100644
--- a/tests/Tgstation.Server.Tests/TestRepository.cs
+++ b/tests/Tgstation.Server.Tests/TestRepository.cs
@@ -42,10 +42,10 @@ namespace Tgstation.Server.Tests
 
 				const string StartSha = "af4da8beb9f9b374b04a3cc4d65acca662e8cc1a";
 				await repo.CheckoutObject(StartSha, null, null, true, new JobProgressReporter(Mock.Of<ILogger<JobProgressReporter>>(), null, (stage, progress) => { }), CancellationToken.None);
-				var result = await repo.ShaIsParent("2f8588a3ca0f6b027704a2a04381215619de3412", CancellationToken.None);
+				var result = await repo.CommittishIsParent("2f8588a3ca0f6b027704a2a04381215619de3412", CancellationToken.None);
 				Assert.IsTrue(result);
 				Assert.AreEqual(StartSha, repo.Head);
-				result = await repo.ShaIsParent("f636418bf47d238d33b0e4a34f0072b23a8aad0e", CancellationToken.None);
+				result = await repo.CommittishIsParent("f636418bf47d238d33b0e4a34f0072b23a8aad0e", CancellationToken.None);
 				Assert.IsFalse(result);
 				Assert.AreEqual(StartSha, repo.Head);
 			}