diff --git a/.github/workflows/alert-discord.yml b/.github/workflows/alert-discord.yml
index af29b7e..8aa5ab6 100644
--- a/.github/workflows/alert-discord.yml
+++ b/.github/workflows/alert-discord.yml
@@ -25,7 +25,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "singlethreaded"]'
     secrets:
       DISCORD_WEBHOOK_URL:
         description: "The Discord Webhook URL."
@@ -36,7 +36,7 @@ on:
 
 jobs:
   send-discord-alert:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     name: Send Alert to Discord
     steps:
       # This step assumes artifacts are already in the workspace (e.g., from a previous job or checked out code).
diff --git a/.github/workflows/gh-pr-assignees.yml b/.github/workflows/gh-pr-assignees.yml
index a2e8855..5768f70 100644
--- a/.github/workflows/gh-pr-assignees.yml
+++ b/.github/workflows/gh-pr-assignees.yml
@@ -20,7 +20,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "singlethreaded"]'
     secrets:
       gh_token:
         description: "GitHub token with permissions to read repo data and write to PRs (assign users)."
@@ -29,7 +29,7 @@ on:
 jobs:
   assign_commit_authors:
     name: Assign Commit Authors
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     steps:
       - name: Get PR Commit Author Logins
         id: get_authors
diff --git a/.github/workflows/gh-sync.yml b/.github/workflows/gh-sync.yml
index f509976..1c98057 100644
--- a/.github/workflows/gh-sync.yml
+++ b/.github/workflows/gh-sync.yml
@@ -6,7 +6,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "singlethreaded"]'
       fail_on_error:
         description: "If true, the job will fail if sync operation fails."
         required: false
@@ -30,7 +30,7 @@ on:
 jobs:
   sync-workflows:
     name: Sync Workflow Files
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       files_synced: ${{ steps.push-changes.outputs.pushed }}
     permissions:
diff --git a/.github/workflows/gh-test-downstream.yml b/.github/workflows/gh-test-downstream.yml
index 808b270..190c0be 100644
--- a/.github/workflows/gh-test-downstream.yml
+++ b/.github/workflows/gh-test-downstream.yml
@@ -10,7 +10,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "multithreaded"]'
     secrets:
       PAT_TOKEN:
         description: "Personal Access Token for cloning/pushing to downstream repos and API calls."
@@ -22,7 +22,7 @@ on:
 jobs:
   stage-downstream:
     name: Stage to Downstream Repositories
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     permissions:
       contents: write # To checkout repository and push changes to downstream repos
       pull-requests: write # To create pull requests in downstream repos
@@ -223,7 +223,7 @@ jobs:
 
   check-downstream-prs:
     needs: stage-downstream
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     steps:
       - name: Download PR data
         uses: actions/download-artifact@v4
diff --git a/.github/workflows/publish-py-pypi.yml b/.github/workflows/publish-py-pypi.yml
index b72e13a..3dbae13 100644
--- a/.github/workflows/publish-py-pypi.yml
+++ b/.github/workflows/publish-py-pypi.yml
@@ -21,7 +21,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "singlethreaded"]'
     secrets:
       TWINE_USERNAME:
         description: "Twine username (usually __token__ for API tokens)"
@@ -33,7 +33,7 @@ on:
 jobs:
   build-and-publish:
     name: Build and Publish to PyPI
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     defaults:
       run:
         working-directory: ${{ inputs.working-directory }}
diff --git a/.github/workflows/publish-storybook.yml b/.github/workflows/publish-storybook.yml
index af9b1f9..e836f15 100644
--- a/.github/workflows/publish-storybook.yml
+++ b/.github/workflows/publish-storybook.yml
@@ -31,7 +31,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "singlethreaded"]'
 permissions:
   contents: read # To checkout the repository
   pages: write # To deploy to GitHub Pages
@@ -40,7 +40,7 @@ permissions:
 jobs:
   build-and-deploy-storybook:
     name: Build and Deploy Storybook
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     defaults:
       run:
         working-directory: ${{ inputs.working-directory }}
diff --git a/.github/workflows/publish-ts-npm.yml b/.github/workflows/publish-ts-npm.yml
index 63f6d21..d5baa56 100644
--- a/.github/workflows/publish-ts-npm.yml
+++ b/.github/workflows/publish-ts-npm.yml
@@ -26,7 +26,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "singlethreaded"]'
     secrets:
       NPM_TOKEN:
         description: "NPM authentication token"
@@ -35,7 +35,7 @@ on:
 jobs:
   build-and-publish:
     name: Build and Publish to npm
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     defaults:
       run:
         working-directory: ${{ inputs.working-directory }}
diff --git a/.github/workflows/sync-meta.yml b/.github/workflows/sync-meta.yml
index 5c58ae7..d000b8e 100644
--- a/.github/workflows/sync-meta.yml
+++ b/.github/workflows/sync-meta.yml
@@ -27,11 +27,11 @@ on:
       runs_on:
         required: false
         type: string
-        default: "ubuntu-latest"
+        default: '["ubuntu-latest"]'
 
 jobs:
   sync:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     steps:
       - name: Checkout source repo (self)
         uses: actions/checkout@v4
diff --git a/.github/workflows/test-py-lint.yml b/.github/workflows/test-py-lint.yml
index 761fb7b..6248055 100644
--- a/.github/workflows/test-py-lint.yml
+++ b/.github/workflows/test-py-lint.yml
@@ -6,7 +6,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "multithreaded"]'
     outputs:
       auto_formatted:
         description: "Whether Black auto-formatted files and pushed changes."
@@ -14,7 +14,7 @@ on:
 
 jobs:
   lint:
-    runs-on: self-hosted
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     name: Python Black Lint Check
     outputs:
       auto_formatted: ${{ steps.push-changes.outputs.pushed }}