diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index ece1081030..c0bf36709e 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -71,7 +71,7 @@ build_nix_master:
   - if: '$CI_PIPELINE_SOURCE == "schedule"'
     when: always
   script:
-  - nix-build --pure -A emuhawk --arg doCheck true
+  - nix-build --pure -A emuhawk
   stage: test
 
 build_nix_prev_release:
@@ -81,7 +81,7 @@ build_nix_prev_release:
   - if: '$CI_PIPELINE_SOURCE == "schedule"'
     when: always
   script:
-  - nix-build --pure -A emuhawk-latest --arg doCheck true
+  - nix-build --pure -A emuhawk-latest
   stage: test
 
 check_style:
diff --git a/Dist/historical.nix b/Dist/historical.nix
index ba1273fc65..2e6027b172 100644
--- a/Dist/historical.nix
+++ b/Dist/historical.nix
@@ -216,6 +216,7 @@ in {
 		releaseArtifactNeedsLowercaseAsms = !isVersionAtLeast "2.3.3" version;
 		releaseArtifactNeedsOTKAsmConfig = isVersionAtLeast "2.3.3" version && !isVersionAtLeast "2.5" version; # see a1b501fe5
 		releaseArtifactNeedsVBDotnetReference = !isVersionAtLeast "2.5.1" version;
+		testProjectNeedsCIEnvVar = !isVersionAtLeast "2.8" version; # platform-specific tests don't run "in CI" because they assume Arch filesystem conventions (on Linux)--before 908d4519c, `-p:ContinuousIntegrationBuild=true` wasn't respected but `GITLAB_CI` was
 		versionProjNeedsDoubleBuild = !isVersionAtLeast "2.9.1" version;
 		#TODO warn about missing/broken features when eval'ing older releases
 	} // hawkSourceInfo;
diff --git a/Dist/packages.nix b/Dist/packages.nix
index f620995316..29508c5412 100644
--- a/Dist/packages.nix
+++ b/Dist/packages.nix
@@ -103,7 +103,7 @@
 		buildType = buildConfig; #TODO move debug symbols to `!debug`?
 		extraDotnetBuildFlags = let
 			s = lib.optionalString (extraDefines != "") "-p:MachineExtraCompilationFlag=${extraDefines} ";
-		in "-maxcpucount:$NIX_BUILD_CORES -p:BuildInParallel=true --no-restore ${s}${extraDotnetBuildFlags}";
+		in "-maxcpucount:$NIX_BUILD_CORES -p:BuildInParallel=true --no-restore -p:ContinuousIntegrationBuild=true ${s}${extraDotnetBuildFlags}";
 		buildPhase = ''
 			runHook preBuild
 
@@ -116,14 +116,12 @@
 			runHook postBuild
 		'';
 		checkNativeInputs = finalAttrs.buildInputs;
-		/** TODO WHY DOESN'T THIS WORK */
 		checkPhase = ''
 			runHook preCheck
 
-			export GITLAB_CI=1 # pretend to be in GitLab CI -- platform-specific tests don't run in CI because they assume an Arch filesystem (on Linux hosts)
-			# from 2.7.1, use standard -p:ContinuousIntegrationBuild=true instead
 			export LD_LIBRARY_PATH="$LD_LIBRARY_PATH:${lib.makeLibraryPath finalAttrs.checkNativeInputs}"
-			Dist/BuildTest${finalAttrs.buildType}.sh ${finalAttrs.extraDotnetBuildFlags}
+			${if hawkSourceInfo.testProjectNeedsCIEnvVar then ''export GITLAB_CI=1
+			'' else ""}Dist/BuildTest${finalAttrs.buildType}.sh ${finalAttrs.extraDotnetBuildFlags}
 
 			# can't build w/ extra Analyzers, it fails to restore :(
 #			Dist/Build${finalAttrs.buildType}.sh -p:MachineRunAnalyzersDuringBuild=true ${finalAttrs.extraDotnetBuildFlags}
diff --git a/default.nix b/default.nix
index bad8c36714..fc5505ecd5 100644
--- a/default.nix
+++ b/default.nix
@@ -43,7 +43,7 @@ in {
 , buildConfig ? "Release" # "Debug"/"Release"
 , debugPInvokes ? false # forwarded to Dist/launch-scripts.nix
 , debugDotnetHostCrashes ? false # forwarded to Dist/launch-scripts.nix
-, doCheck ? false # runs `Dist/BuildTest${buildConfig}.sh`
+, doCheck ? true # runs `Dist/BuildTest${buildConfig}.sh`
 , emuhawkBuildFlavour ? "NixHawk"
 , extraDefines ? "" # added to `<DefineConstants/>`, so ';'-separated
 , extraDotnetBuildFlags ? "" # currently passed to EVERY `dotnet build` and `dotnet test` invocation (and does not replace the flags for parallel compilation added by default)