diff --git a/.github/workflows/byond.yml b/.github/workflows/byond.yml
new file mode 100644
index 00000000000..8e958bbfea4
--- /dev/null
+++ b/.github/workflows/byond.yml
@@ -0,0 +1,93 @@
+name: BYOND tests
+
+on:
+  push:
+    branches:
+    - master
+  pull_request:
+    branches:
+    - master
+
+jobs:
+  lint:
+    if: "!contains(github.event.head_commit.message, '[ci skip]')"
+    runs-on: ubuntu-20.04
+    steps:
+      - uses: actions/checkout@v2
+      - name: Install
+        run: |
+          pip install --user -r ./tools/requirements.txt
+          chmod +x ./scripts/code_check.sh && ./scripts/code_check.sh $PWD
+          bash tools/ci/install_spaceman_dmm.sh dreamchecker
+      - name: Code checks
+        run: |
+          awk -f tools/indentation.awk **/*.dm
+          python3 tools/TagMatcher/tag-matcher.py ../..
+          python3 tools/GenerateChangelog/ss13_genchangelog.py html/changelog.html html/changelogs --dry-run
+          python3 tools/mapmerge2/travis_mapcheck.py
+          echo "6a5ae087fe5bfa66e52e508655e57120 *html/changelogs/example.yml" | md5sum -c -
+      - name: Run dreamchecker
+        run: ~/dreamchecker > ${GITHUB_WORKSPACE}/output-annotations.txt 2>&1
+      - name: Annotate Lints
+        uses: yogstation13/DreamAnnotate@v1
+        if: always()
+        with:
+          outputFile: output-annotations.txt
+
+  unit-test-linux:
+    if: "!contains(github.event.head_commit.message, '[ci skip]')"
+    strategy:
+      matrix:
+        map: [runtime, aurora, exodus]
+    runs-on: ubuntu-20.04
+    needs: lint
+    services:
+      mariadb:
+        image: mariadb:latest
+        ports:
+          - 3306
+        env:
+          MYSQL_USER: build
+          MYSQL_PASSWORD: build
+          MYSQL_DATABASE: game
+          MYSQL_ROOT_PASSWORD: root
+    steps:
+      - uses: actions/checkout@v2
+      - name: Install BYOND
+        run: |
+          source .versions.sh
+          sudo dpkg --add-architecture i386
+          sudo apt-get update
+          sudo apt-get install -y gcc-multilib libssl1.1:i386
+          bash tools/ci/install_byond.sh
+          source $HOME/BYOND/byond/bin/byondsetup
+          echo "Getting rust_g from https://github.com/Aurorastation/rust-g/releases/download/${RUST_G_VERSION}/librust_g.so"
+          wget "https://github.com/Aurorastation/rust-g/releases/download/${RUST_G_VERSION}/librust_g.so" -O ./librust_g.so
+          chmod +x ./librust_g.so
+          ldd ./librust_g.so
+      - name: Install Flyway
+        run: |
+          source .versions.sh
+          bash scripts/install-flyway.sh
+      - name: Migrate database
+        env:
+          PORT: ${{ job.services.mariadb.ports[3306] }}
+        run: |
+          source .versions.sh
+          $HOME/flyway-$FLYWAY_BUILD/flyway migrate -user=root -password=root -url="jdbc:mariadb://localhost:$PORT/game"
+      - name: Build
+        run: |
+          export LD_LIBRARY_PATH=./:$PWD:$HOME/BYOND/byond/bin:/usr/local/lib:$LD_LIBRARY_PATH
+          scripts/dm.sh -DUNIT_TEST -M${{ matrix.map }} aurorastation.dme
+          grep "0 warnings" build_log.txt
+      - name: Run tests
+        env:
+          PORT: ${{ job.services.mariadb.ports[3306] }}
+        run: |
+          export LD_LIBRARY_PATH=./:$PWD:$HOME/BYOND/byond/bin:/usr/local/lib:$LD_LIBRARY_PATH
+          cp config/example/* config/ && cp config/ut/config-db.txt config/config.txt && cp config/ut/dbconfig.txt config/dbconfig.txt
+          echo "PORT $PORT" >> config/dbconfig.txt
+          $HOME/BYOND/byond/bin/DreamDaemon aurorastation.dmb -invisible -trusted -core 2>&1 | tee log.txt
+          grep "All Unit Tests Passed" log.txt
+          (! grep "runtime error:" log.txt)
+
diff --git a/.versions.sh b/.versions.sh
new file mode 100644
index 00000000000..9a8f5561133
--- /dev/null
+++ b/.versions.sh
@@ -0,0 +1,8 @@
+#!/bin/sh
+
+export BYOND_MAJOR=514
+export BYOND_MINOR=1560
+
+export RUST_G_VERSION=v0.4.2+a3
+export FLYWAY_BUILD=5.2.4
+export SPACEMAN_DMM_VERSION=suite-1.6
diff --git a/SQL/migrate/V056__sql_admins_table.sql b/SQL/migrate/V056__sql_admins_table.sql
index 70704c0eb03..8aa76809962 100644
--- a/SQL/migrate/V056__sql_admins_table.sql
+++ b/SQL/migrate/V056__sql_admins_table.sql
@@ -1,6 +1,6 @@
----
---- Adds the ss13_admins SQL table again.
----
+--
+-- Adds the ss13_admins SQL table again.
+--
 
 CREATE TABLE `ss13_admins` (
   `ckey` VARCHAR(50) NOT NULL,
@@ -15,4 +15,4 @@ ALTER TABLE `ss13_player`
   DROP COLUMN `rank`,
   DROP COLUMN `flags`;
 
-DROP TABLE `ss13_admin_log`;
\ No newline at end of file
+DROP TABLE `ss13_admin_log`;
diff --git a/SQL/migrate/V057__cargo_logging_table.sql b/SQL/migrate/V057__cargo_logging_table.sql
index d1a94ec2f95..28bdddb4ac7 100644
--- a/SQL/migrate/V057__cargo_logging_table.sql
+++ b/SQL/migrate/V057__cargo_logging_table.sql
@@ -1,6 +1,6 @@
----
---- Adds the cargo logging tables
----
+--
+-- Adds the cargo logging tables
+--
 
 CREATE TABLE `ss13_cargo_orderlog` (
 	`id` INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,
diff --git a/SQL/migrate/V058__autohiss_setup.sql b/SQL/migrate/V058__autohiss_setup.sql
index 481001ee56f..7182495dd4a 100644
--- a/SQL/migrate/V058__autohiss_setup.sql
+++ b/SQL/migrate/V058__autohiss_setup.sql
@@ -1,6 +1,6 @@
----
---- Puts autohiss in character setup
----
+--
+-- Puts autohiss in character setup
+--
 
 ALTER TABLE `ss13_characters`
 	ADD COLUMN `autohiss` TINYINT NOT NULL DEFAULT 0 AFTER `accent`;
diff --git a/code/modules/mob/living/silicon/robot/custom_sprites.dm b/code/modules/mob/living/silicon/robot/custom_sprites.dm
index a833c40e48d..8b3227234b8 100644
--- a/code/modules/mob/living/silicon/robot/custom_sprites.dm
+++ b/code/modules/mob/living/silicon/robot/custom_sprites.dm
@@ -11,6 +11,8 @@ var/list/robot_custom_icons
 	return 1
 
 /mob/living/silicon/robot/proc/set_custom_sprite()
+	if(!(name in robot_custom_icons))
+		return
 	var/datum/custom_synth/sprite = robot_custom_icons[name]
 	if(istype(sprite) && sprite.synthckey == ckey)
 		custom_sprite = 1
@@ -21,4 +23,4 @@ var/list/robot_custom_icons
 				icon_state = "[sprite.synthicon]-Standard"
 			else
 				to_chat(src, SPAN_WARNING("Could not locate [sprite.synthicon]-Standard sprite."))
-				icon = 'icons/mob/robots.dmi'
\ No newline at end of file
+				icon = 'icons/mob/robots.dmi'
diff --git a/config/ut/dbconfig.txt b/config/ut/dbconfig.txt
index eae86ee7035..992a0467cac 100644
--- a/config/ut/dbconfig.txt
+++ b/config/ut/dbconfig.txt
@@ -2,10 +2,9 @@
 
 # Server the MySQL database can be found at
 # Examples: localhost, 200.135.5.43, www.mysqldb.com, etc.
-ADDRESS mariadb
+ADDRESS 127.0.0.1
 
 # MySQL server port (default is 3306)
-PORT 3306
 
 # Database the population, death, karma, etc. tables may be found in
 DATABASE game
diff --git a/scripts/sourcedm.sh b/scripts/sourcedm.sh
index 5737d4e6b4a..3ae8d22da4a 100755
--- a/scripts/sourcedm.sh
+++ b/scripts/sourcedm.sh
@@ -28,6 +28,10 @@ else
     then
         export DM='/usr/share/byond/bin/DreamMaker'
         return 0
+    elif [[ -a "$HOME/BYOND/byond/bin/DreamMaker" ]]
+    then
+        export DM="$HOME/BYOND/byond/bin/DreamMaker"
+        return 0
     fi
 fi
 
diff --git a/tools/ci/install_byond.sh b/tools/ci/install_byond.sh
new file mode 100644
index 00000000000..4d8822e6cf1
--- /dev/null
+++ b/tools/ci/install_byond.sh
@@ -0,0 +1,21 @@
+#!/bin/bash
+set -euo pipefail
+
+source .versions.sh
+
+if [ -d "$HOME/BYOND/byond/bin" ] && grep -Fxq "${BYOND_MAJOR}.${BYOND_MINOR}" $HOME/BYOND/version.txt;
+then
+  echo "Using cached directory."
+else
+  echo "Setting up BYOND."
+  rm -rf "$HOME/BYOND"
+  mkdir -p "$HOME/BYOND"
+  cd "$HOME/BYOND"
+  curl "http://www.byond.com/download/build/${BYOND_MAJOR}/${BYOND_MAJOR}.${BYOND_MINOR}_byond_linux.zip" -o byond.zip
+  unzip byond.zip
+  rm byond.zip
+  cd byond
+  make here
+  echo "$BYOND_MAJOR.$BYOND_MINOR" > "$HOME/BYOND/version.txt"
+  cd ~/
+fi
diff --git a/tools/ci/install_spaceman_dmm.sh b/tools/ci/install_spaceman_dmm.sh
new file mode 100644
index 00000000000..9b96096343d
--- /dev/null
+++ b/tools/ci/install_spaceman_dmm.sh
@@ -0,0 +1,19 @@
+#!/bin/bash
+set -euo pipefail
+
+source .versions.sh
+
+if [ ! -f ~/$1 ]; then
+	mkdir -p "$HOME/SpacemanDMM"
+	CACHEFILE="$HOME/SpacemanDMM/$1"
+
+	if ! [ -f "$CACHEFILE.version" ] || ! grep -Fxq "$SPACEMAN_DMM_VERSION" "$CACHEFILE.version"; then
+		wget -O "$CACHEFILE" "https://github.com/SpaceManiac/SpacemanDMM/releases/download/$SPACEMAN_DMM_VERSION/$1"
+		chmod +x "$CACHEFILE"
+		echo "$SPACEMAN_DMM_VERSION" >"$CACHEFILE.version"
+	fi
+
+	ln -s "$CACHEFILE" ~/$1
+fi
+
+~/$1 --version