apache · skrawcz · Mar 28, 2026 · Apr 4, 2026 · Apr 13, 2026
diff --git a/.rat-excludes b/.rat-excludes
@@ -15,5 +15,8 @@ SHORT_LICENSE\.md
 \.gitignore
 \.rat-excludes
 
+# Third-party vendored code with its own license (MIT)
+.*databackend\.py
+
 # PKG-INFO (generated metadata)
 PKG-INFO
diff --git a/hamilton/version.py b/hamilton/version.py
@@ -15,4 +15,4 @@
 # specific language governing permissions and limitations
 # under the License.
 
-VERSION = (1, 89, 0)
+VERSION = (1, 90, 0)
diff --git a/pyproject.toml b/pyproject.toml
@@ -21,7 +21,7 @@ build-backend = "flit_core.buildapi"
 
 [project]
 name = "apache-hamilton"
-version = "1.89.0"  # NOTE: keep this in sync with hamilton/version.py
+version = "1.90.0"  # NOTE: keep this in sync with hamilton/version.py
 # TODO: flip back to dynamic once hamilton version is a string. Flit doesn't handle tuples.
 # dynamic = ["version"]
 description = "Apache Hamilton (incubating) is a lightweight Python library for directed acyclic graphs (DAGs) of transformations. Your DAG is **portable**; it runs anywhere Python runs, whether it's a script, notebook, Airflow pipeline, FastAPI server, etc. Your DAG is **expressive**; Apache Hamilton has extensive features to define and modify the execution of a DAG (e.g., data validation, experiment tracking, remote execution)."

diff --git a/scripts/README.md b/scripts/README.md
@@ -132,141 +132,142 @@ uv run twine upload dist/apache_hamilton-1.90.0.tar.gz dist/apache_hamilton-1.90
 
 If you're voting on a release, follow these steps to verify the release candidate.
 
-## Complete Verification Workflow
+## Step 1: Download the Artifacts
 
 ```bash
 # Set version and RC number
 export VERSION=1.90.0
 export RC=0
 export PACKAGE=apache-hamilton  # or apache-hamilton-sdk, etc.
 
-# 1. Download all artifacts from SVN
-svn export https://dist.apache.org/repos/dist/dev/incubator/hamilton/${PACKAGE}-${VERSION}-incubating-RC${RC}/ hamilton-rc${RC}
+# Derived names (dashes for tarball, underscores for wheel)
+export SRC_TAR=${PACKAGE}-${VERSION}-incubating-src.tar.gz
+export WHEEL_NAME=$(echo ${PACKAGE} | tr '-' '_')-${VERSION}-py3-none-any.whl
+export EXTRACTED_DIR=$(echo ${PACKAGE} | tr '-' '_')-${VERSION}
+
+# Download all artifacts from SVN
+svn export https://dist.apache.org/repos/dist/dev/incubator/hamilton/${PACKAGE}/${VERSION}-RC${RC}/ hamilton-rc${RC}
 cd hamilton-rc${RC}
 
-# 2. Import KEYS file and verify GPG signatures
+# Import the KEYS file
 wget https://downloads.apache.org/incubator/hamilton/KEYS
 gpg --import KEYS
+```
 
-# Verify sdist signature
-gpg --verify ${PACKAGE}-${VERSION}-incubating.tar.gz.asc ${PACKAGE}-${VERSION}-incubating.tar.gz
+## Step 2: Extract and Set Up
 
-# Verify wheel signature (note: underscores in wheel filenames)
-WHEEL_NAME=$(echo ${PACKAGE} | tr '-' '_')-${VERSION}-py3-none-any.whl
-gpg --verify ${WHEEL_NAME}.asc ${WHEEL_NAME}
+```bash
+# Extract the source archive
+tar -xzf ${SRC_TAR}
+cd ${EXTRACTED_DIR}/
 
-# 3. Verify SHA512 checksums
-shasum -a 512 -c ${PACKAGE}-${VERSION}-incubating.tar.gz.sha512
-shasum -a 512 -c ${WHEEL_NAME}.sha512
+# Create a fresh environment and install build tools
+uv venv --python 3.11 --clean
+uv sync --group release
 
-# 4. Extract the source archive and build from source
-tar -xzf ${PACKAGE}-${VERSION}-incubating.tar.gz
-cd ${PACKAGE}-${VERSION}-incubating/
+# Download Apache RAT for license verification
+curl -O https://repo1.maven.org/maven2/org/apache/rat/apache-rat/0.15/apache-rat-0.15.jar
 ```
 
-## Build from Source with uv
+## Step 3: Run Automated Verification
 
-All remaining steps assume you are inside the extracted source directory
-(`${PACKAGE}-${VERSION}-incubating/`) from the step above.
+The verification script checks GPG signatures, SHA512 checksums, and Apache license headers in one command.
+The script looks for artifacts in a `dist/` directory by default, so first copy them there:
 
 ```bash
-# Create a fresh environment and install build tools
-uv venv --python 3.11 --clean
-uv sync --group release
+# Copy artifacts into dist/ so the verification script can find them
+mkdir -p dist
+cp ../${SRC_TAR}* dist/
+cp ../${WHEEL_NAME}* dist/
+
+# Verify everything (signatures + checksums + license headers)
+uv run python scripts/verify_apache_artifacts.py all --rat-jar apache-rat-0.15.jar
+```
+
+You can also run individual checks:
 
+```bash
+# Signatures and checksums only
+uv run python scripts/verify_apache_artifacts.py signatures
+
+# License headers only
+uv run python scripts/verify_apache_artifacts.py licenses --rat-jar apache-rat-0.15.jar
+
+# Validate wheel metadata
+uv run python scripts/verify_apache_artifacts.py twine-check
+
+# Inspect artifact contents
+uv run python scripts/verify_apache_artifacts.py list-contents dist/${SRC_TAR}
+uv run python scripts/verify_apache_artifacts.py list-contents dist/${WHEEL_NAME}
+```
+
+## Step 4: Build from Source
+
+```bash
 # Build the wheel from source
 uv run flit build --no-use-vcs
 
 # Install the wheel you just built
-uv pip install dist/apache_hamilton-${VERSION}-py3-none-any.whl
+uv pip install dist/${WHEEL_NAME}
 ```
 
-## Run Tests
+## Step 5: Run Tests
 
 ```bash
-# Install test dependencies (uses the test dependency group from pyproject.toml)
+# Install test dependencies
 uv sync --group test
 
 # Run core unit tests
 uv run pytest tests/ -x -q
 
 # Run plugin tests
-uv run pytest plugin_tests/ -x -q
+# Note: some plugin tests require optional dependencies (ray, spark, vaex).
+# Exclude any that are not installed in your environment:
+uv run pytest plugin_tests/ -x -q \
+    --ignore=plugin_tests/h_ray \
+    --ignore=plugin_tests/h_spark \
+    --ignore=plugin_tests/h_vaex
 ```
 
-## Run Examples
+## Step 6: Run Examples
 
-The source archive includes representative examples to verify Hamilton works end-to-end. Each example may require additional dependencies.
+The source archive includes representative examples to verify Hamilton works end-to-end.
 
-### Hello World (no extra deps)
 ```bash
-cd examples/hello_world
-uv run python my_script.py
-cd ../..
-```
+# Hello World (no extra deps)
+uv run python examples/hello_world/my_script.py
 
-### Data Quality with Pandera
-```bash
-uv pip install pandera
+# Data Quality with Pandera (must run from its directory for CSV data file)
 cd examples/data_quality/simple
 uv run python run.py
 cd ../../..
-```
 
-### Function Reuse
-```bash
-cd examples/reusing_functions
-uv run python run.py
-cd ../..
-```
+# Function Reuse
+uv run python examples/reusing_functions/main.py
 
-### Schema Validation
-```bash
-cd examples/schema
-uv run python run.py
-cd ../..
-```
+# Schema Validation
+uv run python examples/schema/dataflow.py
 
-### Materialization (Pandas)
-```bash
-uv pip install openpyxl xlsxwriter
-cd examples/pandas/materialization
-uv run python run.py
-cd ../../..
+# Materialization (Pandas)
+uv run python examples/pandas/materialization/my_script.py
 ```
 
-## Verification Script
-
-For automated verification of signatures, checksums, and license compliance, use the verification script.
-Run these from inside the extracted source directory (`${PACKAGE}-${VERSION}-incubating/`).
-
-### Prerequisites
-
-Download Apache RAT for license verification (into the extracted source directory):
+## Manual Signature Verification (alternative to Step 3)
 
-```bash
-curl -O https://repo1.maven.org/maven2/org/apache/rat/apache-rat/0.15/apache-rat-0.15.jar
-```
-
-### Running Verification
+If you prefer to verify signatures and checksums manually instead of using the verification script:
 
 ```bash
-# Run from the extracted source directory (${PACKAGE}-${VERSION}-incubating/)
-# Verify GPG signatures and SHA512 checksums
-uv run python scripts/verify_apache_artifacts.py signatures
-
-# Verify license headers (requires Apache RAT)
-uv run python scripts/verify_apache_artifacts.py licenses --rat-jar apache-rat-0.15.jar
-
-# Verify everything
-uv run python scripts/verify_apache_artifacts.py all --rat-jar apache-rat-0.15.jar
+# From the hamilton-rc${RC}/ directory (before extracting)
 
-# Inspect artifact contents
-uv run python scripts/verify_apache_artifacts.py list-contents dist/apache-hamilton-1.90.0-incubating.tar.gz
-uv run python scripts/verify_apache_artifacts.py list-contents dist/apache_hamilton-1.90.0-py3-none-any.whl
+# Verify GPG signatures
+gpg --verify ${SRC_TAR}.asc ${SRC_TAR}
+gpg --verify ${WHEEL_NAME}.asc ${WHEEL_NAME}
 
-# Validate wheel metadata
-uv run python scripts/verify_apache_artifacts.py twine-check
+# Verify SHA512 checksums
+# Note: the .sha512 files contain only the raw hash (no filename),
+# so `shasum -c` won't work. Compare hashes manually instead:
+echo "$(cat ${SRC_TAR}.sha512)  ${SRC_TAR}" | shasum -a 512 -c -
+echo "$(cat ${WHEEL_NAME}.sha512)  ${WHEEL_NAME}" | shasum -a 512 -c -
 ```
 
 # Local Development