Skip to content

pyside6-scintilla — Project Mission & Background

What is this project?

pyside6-scintilla is a permissively-licensed Python binding for the Scintilla source code editing component, targeting PySide6 (the official Qt for Python project).

The bindings are built with shiboken6 (the same binding generator used by PySide6 itself) and packaged with scikit-build-core + CMake.

Why does this exist?

The established option for using Scintilla from Python with Qt is QScintilla by Riverbank Computing, with Python bindings via PyQt6-QScintilla. However:

  • QScintilla is licensed under GPLv3 or a paid commercial license — which prevents use in closed-source or permissively-licensed projects without purchasing a commercial license.
  • QScintilla targets PyQt6, not PySide6. There are no official PySide6 bindings.

Scintilla itself is licensed under the Historical Permission Notice and Disclaimer (HPND) — a permissive license with no copyleft, compatible with MIT, BSD, commercial, and closed-source use. This project exposes that permissive core directly to PySide6 users, without the GPL encumbrance.

Prior work by the same author

Two earlier prototype projects explored this space:

  • bscintillaedit — on PyPI, Windows-only wheel, wraps ScintillaEditBase inside a QScrollArea-derived widget.
  • pyside6-scintilla — on GitLab, archived, simpler binding experiment.

pyside6-scintilla on PyPI/GitHub is the clean, properly packaged successor to both.

Licensing

Component License
Scintilla / Lexilla C++ source HPND (permissive, no copyleft)
shiboken6 binding glue code MIT
This project overall MIT

The project must not depend on or bundle any GPL or LGPL code at runtime in a way that would require users to open-source their applications.

Technical approach

  • Scintilla is vendored as a subtree/submodule pinned to a stable release tag (not hg tip). Updates happen deliberately when a new Scintilla release is tested.
  • shiboken6 generates the Python ↔ C++ bridge from a typesystem XML file.
  • scikit-build-core drives the CMake build and produces PEP 517-compliant wheels.
  • cibuildwheel on GitHub Actions builds wheels for all three platforms when a GitHub Release is published, then publishes to PyPI via trusted publishing (OIDC) — first to TestPyPI as a tracer, then to the real index.
  • uv is used for local development environment management.

Scope

The goal is a faithful, low-level binding — exposing the Scintilla API to PySide6 as a QWidget-compatible widget that can be dropped into any PySide6 application. It is not a goal to re-implement QScintilla's high-level API (auto-completion helpers, lexer configuration wrappers, etc.) in this package. That higher-level layer can be built on top by consumers.

Target platforms

Platform Architecture Notes
Linux x86_64, aarch64 manylinux wheels via cibuildwheel
Windows x86_64 MSVC build
macOS arm64 (Apple Silicon) Primary test machine: M1 Mac Mini
macOS x86_64 (Intel) Cross-compiled or CI runner

Development environment

  • Primary dev machine: Windows 11 PC with WSL (Debian/Ubuntu)
  • Secondary machine: macOS M1 Mac Mini
  • Package manager: uv
  • CI: GitHub Actions (free, unlimited for public repos)
  • Wheel builder: cibuildwheel
  • Source control: Git on GitHub (Scintilla itself is on SourceForge/Mercurial — vendored as a release tarball, see "Scintilla version strategy" below, to avoid a hg toolchain dependency)

Scintilla version strategy

Pin to release tarballs, not the hg tip. Check scintilla.org for the latest stable release. Updating Scintilla is a deliberate, tested action — not automatic.

Relationship to Scintilla upstream

This project is a standalone binding — there is no intent to upstream it into Scintilla. Scintilla upstream uses Mercurial on SourceForge and has an informal, maintainer-driven patch process that is not well-suited to accepting a Python/Qt binding. Keeping it separate also means it can evolve independently of Scintilla's release cycle.

PyPI name

pyside6-scintilla — confirmed available at time of project creation (June 2026).

Key decisions log

Decision Rationale
PySide6, not PyQt6 PySide6 is LGPL; PyQt6 is GPL — consistent with permissive goals
shiboken6, not ctypes/cffi Native Qt integration, proper signal/slot support
GitHub, not GitLab Unlimited free CI minutes for public repos; GitLab free tier is 400 min/month
Standalone project, not Scintilla upstream Scintilla upstream is C++ only, hg-based, unlikely to accept a Python binding
Vendor Scintilla releases, not git-cinnabar bridge Simpler, more reproducible, no hg toolchain dependency for contributors
uv for local dev Fast, modern, handles venvs and tool installs cleanly
cibuildwheel Industry standard for multi-platform Python native extension wheels
Depend on PySide6-Essentials, not the PySide6 meta-package (issue #14) The meta-package requires Addons too, so every install pulled ~175 MB (compressed) of modules these bindings never import — 205 MB unpacked of it a full Chromium in Qt6WebEngineCore. Only Core/Gui/Widgets are used, and Core5Compat is vendored into the repaired wheel rather than taken from a PySide6 wheel. Essentials ships the whole PySide6 import namespace (__init__.py, py.typed, all .pyi stubs) plus the CMake config, typesystems and glue the build needs, so nothing is lost; a consumer wanting an add-on depends on PySide6 explicitly.
Single cp311-abi3 wheel per platform, not one per Python version (issue #13) shiboken6's FORCE_LIMITED_API compiles the extension against Python's stable ABI (floor 0x030a0000), so the same build works on 3.11+ without a rebuild — same pattern PySide6's own wheels use. Verified by building once against 3.11 and running the full test suite unmodified under 3.11-3.14.