diff --git a/eng/source-build-tarball-build.yml b/eng/source-build-tarball-build.yml
index 2c7a9ae59..036c285f7 100644
--- a/eng/source-build-tarball-build.yml
+++ b/eng/source-build-tarball-build.yml
@@ -3,8 +3,11 @@ pr: none
 resources:
   pipelines:
   - pipeline: installer-build-resource
-    source: dotnet-installer-official-ci
-    trigger: true # Run pipeline when any run of dotnet-installer-official-ci completes
+    ${{ if eq(variables['System.TeamProject'], 'public') }}:
+      source: installer
+    ${{ if ne(variables['System.TeamProject'], 'public') }}:
+      source: dotnet-installer-official-ci
+    trigger: true # Run pipeline when any run of installer CI completes
 
 stages:
 - stage: build
diff --git a/src/SourceBuild/Arcade/eng/common/templates/job/source-build-run-tarball-build.yml b/src/SourceBuild/Arcade/eng/common/templates/job/source-build-run-tarball-build.yml
index 88ba3f01c..41bea30ac 100644
--- a/src/SourceBuild/Arcade/eng/common/templates/job/source-build-run-tarball-build.yml
+++ b/src/SourceBuild/Arcade/eng/common/templates/job/source-build-run-tarball-build.yml
@@ -27,10 +27,9 @@ jobs:
       Fedora33-Online:
         _runOnline: true
         _Container: mcr.microsoft.com/dotnet-buildtools/prereqs:fedora-33-20210222183538-031e7d2
-      # Disable until prebuilts are eliminated
-      # Fedora33-Offline:
-      #   _runOnline: false
-      #   _Container: mcr.microsoft.com/dotnet-buildtools/prereqs:fedora-33-20210222183538-031e7d2
+      Fedora33-Offline:
+        _runOnline: false
+        _Container: mcr.microsoft.com/dotnet-buildtools/prereqs:fedora-33-20210222183538-031e7d2
   timeoutInMinutes: 210
   variables:
     _TarballDir: $(Build.StagingDirectory)/tarball
@@ -82,10 +81,9 @@ jobs:
       docker run --rm -v $(_TarballDir):/tarball -w /tarball ${networkArgs} $(_Container) ./build.sh ${customBuildArgs} -- /p:CleanWhileBuilding=true
     displayName: Build Tarball
 
-  - ${{ if and(ne(variables['System.TeamProject'], 'public'), notin(variables['Build.Reason'], 'PullRequest')) }}:
-    - publish: '$(_TarballDir)/artifacts/$(_BuildArch)/$(_BuildConfig)/'
-      artifact: $(Agent.JobName)_Artifacts_Attempt$(System.JobAttempt)
-      displayName: Publish Source Build Artifacts
+  - publish: '$(_TarballDir)/artifacts/$(_BuildArch)/$(_BuildConfig)/'
+    artifact: $(Agent.JobName)_Artifacts_Attempt$(System.JobAttempt)
+    displayName: Publish Source Build Artifacts
 
   - script: |
       set -x
diff --git a/src/SourceBuild/tarball/content/smoke-test.sh b/src/SourceBuild/tarball/content/smoke-test.sh
index a64453ba0..334aa8064 100755
--- a/src/SourceBuild/tarball/content/smoke-test.sh
+++ b/src/SourceBuild/tarball/content/smoke-test.sh
@@ -601,6 +601,56 @@ function runXmlDocTests() {
     fi
 }
 
+function runOmniSharpTests() {
+    dotnetCmd=${dotnetDir}/dotnet
+
+    rm -rf workdir
+    mkdir workdir
+    pushd workdir
+
+    curl -sSLO "https://github.com/OmniSharp/omnisharp-roslyn/releases/latest/download/omnisharp-linux-x64.tar.gz"
+
+    mkdir omnisharp
+    pushd omnisharp
+    tar xf "../omnisharp-linux-x64.tar.gz"
+    popd
+
+    # 'blazorwasm' requires prereqs (non-source-built packages) - re-enable with https://github.com/dotnet/source-build/issues/2550
+    for project in blazorserver classlib console mstest mvc nunit web webapp webapi worker xunit ; do
+
+        mkdir hello-$project
+        pushd hello-$project
+
+        "${dotnetCmd}" new $project
+        popd
+
+        ./omnisharp/run -s "$(readlink -f hello-$project)" > omnisharp.log &
+
+        sleep 5
+
+        pkill -P $$
+
+        # Omnisharp spawns off a number of processes. They all include the
+        # current directory as a process argument, so use that to identify and
+        # kill them.
+        pgrep -f "$(pwd)"
+
+        kill "$(pgrep -f "$(pwd)")"
+
+        cat omnisharp.log
+
+        if grep ERROR omnisharp.log; then
+            echo "test failed"
+            exit 1
+        else
+            echo "OK"
+        fi
+
+    done
+
+    popd
+}
+
 function resetCaches() {
     rm -rf "$testingHome"
     mkdir "$testingHome"
@@ -683,10 +733,7 @@ echo SDK under test is:
 export NUGET_PACKAGES="$restoredPackagesDir"
 SOURCE_BUILT_PKGS_PATH="$SCRIPT_ROOT/artifacts/obj/$buildArch/$configuration/blob-feed/packages/"
 export DOTNET_ROOT="$dotnetDir"
-# OSX also requires DOTNET_ROOT to be on the PATH
-if [ "$(uname)" == 'Darwin' ]; then
-    export PATH="$dotnetDir:$PATH"
-fi
+export PATH="$dotnetDir:$PATH"
 
 # Run all tests, local restore sources first, online restore sources second
 if [ "$excludeLocalTests" == "false" ]; then
@@ -727,4 +774,6 @@ fi
 
 runXmlDocTests
 
+runOmniSharpTests
+
 echo "ALL TESTS PASSED!"