typst-pyexec 0.0.3

Reactive Python execution engine for Typst documents

typst_pyexec

typst_pyexec is a reactive Python execution engine for Typst documents.

It executes Python fences inside .typ files, captures outputs (stdout, figures, tables), and injects rendered Typst markup into an intermediate file (*.typst_pyexec.typ) that can be compiled directly.

Requirements

• Python >= 3.10
• Typst compiler for build and watch (default command typst)
• Optional: tinymist for faster live preview (tinymist preview)

Core Capabilities

• Reactive dependency graph based on Python AST analysis
• Incremental execution with source-hash cache
• Persistent Jupyter kernel between builds with cold-kernel hydration
• Matplotlib figure export to SVG with PNG fallback
• Subfigure reconstruction via figure(grid(...))
• DataFrame HTML rendering to Typst #table(...)
• Watch mode with automatic rebuilds and live preview

Installation

pip install typst_pyexec

For development:

uv sync --extra dev

CLI Usage

Build once:

typst_pyexec build document.typ

Watch and rebuild on save:

typst_pyexec watch document.typ

Watch with explicit preview backend:

typst_pyexec watch document.typ --preview-engine auto

Clean local state directory:

typst_pyexec clean

Common options:

• --output-dir <dir>: write intermediate and state outputs to a custom folder (default: source file directory)
• --no-cache: disable cache reads and writes, and execute all cells
• --jobs <n>: reserved for future multi-kernel scheduling (-1 default)
• --compiler <cmd>: Typst compiler binary name or path (default typst)
• watch --preview-engine <auto|tinymist|typst|none>: select live preview backend

Watch mode behavior

• Watch mode regenerates *.typst_pyexec.typ on each save and delegates rendering to a live preview process.
• --preview-engine auto tries tinymist preview first (if tinymist is on PATH), then falls back to typst watch.
• --preview-engine tinymist prefers tinymist preview; if tinymist is unavailable it falls back to typst watch.
• --preview-engine typst always runs typst watch.
• --preview-engine none disables live preview and only refreshes the intermediate file.

Block Options (%|)

Place options at the top of a Python fence:

```python
%| echo: false
%| raw: true
%| figure: true
%| plt-lines.linewidth: 0.8
%| plt-axes.linewidth: 0.6
print("hello")
```

Supported options:

• execute (default true): skip execution when false
• refresh (default false): force this cell to run every build
• echo (default true): show or hide source code
• raw (default true): show or hide textual runtime output (stdout, tracebacks, text/plain bundles)
• figure (default true): show or hide rendered figures
• caption: explicit figure caption override
• label: Typst label for cross-references
• keep-subplots (default false): preserve multi-axis plot as one image
• img-*: passthrough kwargs for Typst image(...)
• fig-*: passthrough kwargs for Typst figure(...)
• grid-*: passthrough kwargs for Typst grid(...)
• grid-columns: explicit columns value for the grid (overrides inferred default)
• plt-*: per-cell matplotlib rcParams overrides (key after plt- maps to rcParam name)

Boolean values are case-insensitive and accept: true/false, yes/no, on/off, 1/0.

plt-* values are parsed as JSON first, then Python literals. If parsing fails, the raw string is used.

Default plt-* values applied to every executed cell:

• lines.linewidth: 0.8
• axes.linewidth: 0.6
• grid.linewidth: 0.2
• axes.grid: true
• lines.markersize: 4 (scatter points are about 2x smaller in area than matplotlib default)

plt-* examples:

• %| plt-lines.linewidth: 0.8
• %| plt-axes.linewidth: 0.6
• %| plt-grid.linewidth: 0.4
• %| plt-axes.grid: true

Precedence order for plot style values:

1. Built-in defaults (values above)
2. %| plt-* metadata options
3. Any matplotlib.rcParams[...] = ... or plt.rcParams.update(...) in Python code

This means Python code always wins over %| plt-*, and %| plt-* wins over defaults.

Behavior notes:

• cell_id is internal and generated automatically.
• Python fences can be indented to fit paragraph or layout context; shared left padding is removed before execution.
• In generated .typst_pyexec.typ, that original block padding is preserved for both rendered source and rendered outputs.
• Option-only edits (including plt-*) do not invalidate cache because cache keys are based on Python source.
• To re-run on option updates, set refresh: true.

Figure and Caption Behavior

• For single-axis plots, title or suptitle text is promoted into the Typst caption when caption is not set.
• For subplot grids, each axis title becomes a child caption; suptitle becomes the outer caption.
• Title and suptitle text are removed from exported images after promotion to captions.
• If SVG export fails and PNG is emitted, renderer auto-resolves PNG paths in final Typst output.

How It Works

1. Parse Python fences from Typst source
2. Build def/use DAG from AST
3. Compute changed cells from source-hash cache
4. Execute required cells in topological groups
5. Capture stdout, display bundles, and figure artifacts
6. Render Typst fragments per cell
7. Inject into document.typst_pyexec.typ
8. Build mode: compile with Typst compiler
9. Watch mode: refresh intermediate file and stream live preview via tinymist preview or typst watch

Caching and Execution Model

• Cache keys are SHA-256 hashes of the Python source for each cell.
• Cache entries are stored under .typst_pyexec/cache.
• --no-cache disables cache reads and writes and forces all executable cells to run.
• refresh: true forces a cell to execute every build but does not cascade to dependents.
• When a kernel is cold or reconnected, typst_pyexec replays prerequisite cells to rebuild namespace state.

Local State

typst_pyexec writes runtime state into .typst_pyexec/ inside the output directory:

• kernel_connection.json: reconnect data for persistent kernel
• cache/: JSON entries keyed by SHA-256 of cell source
• figures/: SVG/PNG artifacts
• notebook.ipynb: synchronized notebook in normal execution mode (original user cells)
• notebook_export.ipynb: synchronized notebook in export mode (figure capture preamble/postamble included)

Notebook Modes

Two notebooks are intentionally generated:

• notebook.ipynb preserves the authored Python cells and attached outputs exactly as written (minimal overhead).
• notebook_export.ipynb wraps each cell with figure-export helpers that invoke optimized functions.

Both notebooks include a setup cell that initializes the environment:

• Normal mode: sets working directory for relative path consistency
• Export mode: sets working directory and imports matplotlib plus save_figures_and_metadata, enabling the export notebook to execute standalone

Development Quality Gates

Run checks locally:

uv run ruff check .
uv run black --check typst_pyexec tests
uv run mypy typst_pyexec
uv run pytest

CI/CD (GitHub Actions)

• CI: matrix on Ubuntu and Windows, Python 3.10-3.12, with lint + format + type-check + tests + coverage artifact
• Release: tag-driven (v*.*.*) build and publish workflow for PyPI using trusted publishing

Workflows are in:

• .github/workflows/ci.yml
• .github/workflows/release.yml

Publish to PyPI

typst_pyexec is already configured for trusted publishing through GitHub Actions.

Release steps:

1. Bump version in pyproject.toml and typst_pyexec/__init__.py.
2. Commit and push to main.
3. Create and push a version tag:

git tag v0.1.1
git push origin v0.1.1

4. GitHub Actions runs .github/workflows/release.yml and publishes to PyPI.

Pre-tag checklist:

1. python -m pytest -q is green.
2. python -m build succeeds.
3. python -m twine check dist/* passes.
4. Version matches in pyproject.toml and typst_pyexec/__init__.py.
5. Git tag matches that version (vX.Y.Z).

Local preflight checks before tagging:

python -m build
python -m twine check dist/*

If you prefer token-based manual publishing:

python -m twine upload dist/*

Use in Other Repositories

After publishing, install as a normal dependency.

With pip:

pip install typst_pyexec

With uv (project dependency):

uv add typst_pyexec

With uvx (run CLI without adding dependency):

uvx typst_pyexec build document.typ

License

MIT