feat: introduce lfx package

.devcontainer/README.md

@@ -33,7 +33,7 @@ You now need to manually build the frontend. Open a new Terminal and run command
 make build_frontend
 ```
 
-This will take a short period of time, you should have a message similar to `Building frontend static files` and the command will complete successfully. 
+This will take a short period of time, you should have a message similar to `Building frontend static files` and the command will complete successfully.
 
 Installation is now complete.
 
@@ -57,4 +57,4 @@ The service will start, and you will may notice a dialog in the lower right indi
 ╰───────────────────────────────────────────────────────────────────────╯
 ```
 
-At this point you can connect to the service via the port, or if the dialog is gone you can find the "Forwarded Address" on the "Ports" tab (which is next the "Terminal" tab). If there is no port forwarded, you can click the "Forward a Port" button on the "Ports" tab, and forward `7860`. 
+At this point you can connect to the service via the port, or if the dialog is gone you can find the "Forwarded Address" on the "Ports" tab (which is next the "Terminal" tab). If there is no port forwarded, you can click the "Forward a Port" button on the "Ports" tab, and forward `7860`.

.github/workflows/cross-platform-test.md

@@ -122,7 +122,7 @@ cross-platform-test.yml
 
 **Key Benefits:**
 - **Single File**: No complex workflow chains or parameter passing issues
-- **Unified Logic**: Same test matrix for all use cases  
+- **Unified Logic**: Same test matrix for all use cases
 - **Smart Routing**: Automatically determines install method based on trigger type
 - **Context-Aware**: Summary messages adapt to manual vs programmatic usage
 
@@ -154,11 +154,11 @@ build-if-needed:
 test-installation:
   steps:
     - name: Determine install method
-      # workflow_dispatch: maps boolean to install method  
+      # workflow_dispatch: maps boolean to install method
       # workflow_call: always uses wheel method
     - name: Install from PyPI
       if: steps.install-method.outputs.method == 'pypi'
-    - name: Install from wheels  
+    - name: Install from wheels
       if: steps.install-method.outputs.method == 'wheel'
 ```
 

.github/workflows/nightly_build.yml

@@ -23,6 +23,7 @@ jobs:
     outputs:
       main_tag: ${{ steps.generate_main_tag.outputs.main_tag }}
       base_tag: ${{ steps.set_base_tag.outputs.base_tag }}
+      lfx_tag: ${{ steps.generate_lfx_tag.outputs.lfx_tag }}
     steps:
       - name: Checkout code
         uses: actions/checkout@v4
@@ -62,6 +63,14 @@ jobs:
           echo "base_tag=$BASE_TAG" >> $GITHUB_OUTPUT
           echo "base_tag=$BASE_TAG"
 
+      - name: Generate LFX nightly tag
+        id: generate_lfx_tag
+        run: |
+          # NOTE: This outputs the tag with the `v` prefix.
+          LFX_TAG="$(uv run ./scripts/ci/lfx_nightly_tag.py)"
+          echo "lfx_tag=$LFX_TAG" >> $GITHUB_OUTPUT
+          echo "lfx_tag=$LFX_TAG"
+
       - name: Commit tag
         id: commit_tag
         run: |
@@ -72,13 +81,17 @@ jobs:
 
           MAIN_TAG="${{ steps.generate_main_tag.outputs.main_tag }}"
           BASE_TAG="${{ steps.generate_base_tag.outputs.base_tag }}"
+          LFX_TAG="${{ steps.generate_lfx_tag.outputs.lfx_tag }}"
           echo "Updating base project version to $BASE_TAG and updating main project version to $MAIN_TAG"
           uv run ./scripts/ci/update_pyproject_combined.py main $MAIN_TAG $BASE_TAG
+          echo "Updating LFX project version to $LFX_TAG"
+          uv run ./scripts/ci/update_lfx_version.py $LFX_TAG
 
           uv lock
           cd src/backend/base && uv lock && cd ../../..
+          cd src/lfx && uv lock && cd ../..
 
-          git add pyproject.toml src/backend/base/pyproject.toml uv.lock src/backend/base/uv.lock
+          git add pyproject.toml src/backend/base/pyproject.toml src/lfx/pyproject.toml uv.lock src/backend/base/uv.lock src/lfx/uv.lock
           git commit -m "Update version and project name"
 
           echo "Tagging main with $MAIN_TAG"
@@ -149,6 +162,31 @@ jobs:
       OPENAI_API_KEY: ${{ secrets.OPENAI_API_KEY }}
       ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
 
+  lfx-tests:
+    if: github.repository == 'langflow-ai/langflow'
+    name: Run LFX Tests
+    needs: create-nightly-tag
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: ["3.10", "3.11", "3.12", "3.13"]
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+        with:
+          ref: ${{ needs.create-nightly-tag.outputs.main_tag }}
+      - name: Setup Environment
+        uses: astral-sh/setup-uv@v6
+        with:
+          enable-cache: true
+          cache-dependency-glob: "uv.lock"
+          python-version: ${{ matrix.python-version }}
+          prune-cache: false
+      - name: Install LFX dependencies
+        run: uv sync --dev --package lfx
+      - name: Run LFX tests
+        run: cd src/lfx && uv run pytest tests/unit -v
+
   # Not making nightly builds dependent on integration test success
   # due to inherent flakiness of 3rd party integrations
   # Revisit when https://github.com/langflow-ai/langflow/pull/3607 is merged.
@@ -163,13 +201,15 @@ jobs:
   release-nightly-build:
     if: github.repository == 'langflow-ai/langflow'
     name: Run Nightly Langflow Build
-    needs: [frontend-tests, backend-unit-tests, create-nightly-tag]
+    needs: [frontend-tests, backend-unit-tests, lfx-tests, create-nightly-tag]
     uses: ./.github/workflows/release_nightly.yml
     with:
       build_docker_base: true
       build_docker_main: true
+      build_lfx: true
       nightly_tag_main: ${{ needs.create-nightly-tag.outputs.main_tag }}
       nightly_tag_base: ${{ needs.create-nightly-tag.outputs.base_tag }}
+      nightly_tag_lfx: ${{ needs.create-nightly-tag.outputs.lfx_tag }}
     secrets: inherit
 
   # slack-notification:

.github/workflows/python_test.yml

@@ -131,6 +131,28 @@ jobs:
           PYLEAK_LOG_LEVEL: debug # enable pyleak logging
           DO_NOT_TRACK: true # disable telemetry reporting
 
+  lfx-tests:
+    name: LFX Tests - Python ${{ matrix.python-version }}
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: ${{ fromJson(inputs.python-versions || '["3.10", "3.11", "3.12", "3.13"]' ) }}
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          ref: ${{ inputs.ref || github.ref }}
+      - name: "Setup Environment"
+        uses: astral-sh/setup-uv@v6
+        with:
+          enable-cache: true
+          cache-dependency-glob: "uv.lock"
+          python-version: ${{ matrix.python-version }}
+          prune-cache: false
+      - name: Run lfx tests
+        run: make lfx_tests
+        env:
+          DO_NOT_TRACK: true # disable telemetry reporting
+
   test-cli:
     name: Test CLI - Python ${{ matrix.python-version }}
     runs-on: ubuntu-latest