Skip to main content

Chemvas — Draw interactively. Automate safely. Export exactly.

CI PyPI Python 3.12+ License: MIT

English · 한국어

Chemvas is an open-source chemical drawing app where chemists and AI agents work on the same editable canvas. Start in the desktop app, let an agent continue through a purpose-built CLI, then open the editable result right back on the canvas.

Draw it yourself. Hand it to AI. Keep editing.

  • Draw it yourself. Sketch structures, insert SMILES, label reaction arrows, and align molecules on the desktop canvas, with autosave and crash recovery. SMILES insertion needs the optional RDKit backend.
  • Hand the same drawing to an AI agent. The CLI can compose documents, inspect stable atom IDs, apply bounded graph patches, check layouts, and render figures without opening the desktop app. Graph Patch binds each proposal to the exact source hash and validates the complete result before writing a new file.
  • Keep editing the result. Composed and patched drawings remain native, reopenable .chemvas documents. Export SVG, PDF, PNG, or TIFF at explicit physical sizes while keeping the editable drawing alongside the figure.

Install

Requires Python 3.12+. Install the optional RDKit backend for SMILES insertion, Molecule Info (formula and identifiers), 3D XYZ export, abbreviation MOL export, Suggest by structure, and generate-precomplex / select-precomplex / pack-step:

pip install "chemvas[rdkit]"
chemvas

pip install chemvas skips RDKit. Drawing, .chemvas save/open, figure export (SVG/PDF/PNG/TIFF, including editable SVG), and plain MOL import/export remain available. Local Windows builds: packaging notes.

Your first reaction scheme

Chemvas walkthrough: insert structures, label an arrow, align the scheme, and export SVG

  1. Choose Ring, type OCc1ccccc1 in its SMILES field, click Insert, then click the canvas. Hover the oxygen, press Enter, label it OH.
  2. Insert O=Cc1ccccc1 to the right. Choose Arrow, drag between the two structures, then double-click the arrow to label it.
  3. Edit ▸ Select All, then Edit ▸ Align ▸ Middle.
  4. Save as .chemvas. File ▸ Export Figure… → Plain SVG, Fit 2-column (174 mm).

The step-by-step guide has the label text and the downloadable files. The drawing is an exercise, not an experimental result.

Scripts

With the downloaded first-scheme.chemvas:

chemvas inspect-document first-scheme.chemvas
chemvas check-layout first-scheme.chemvas
chemvas render-document first-scheme.chemvas --output first-scheme.pdf --width-mm 174

Rendering writes a new file and never touches the source. Composition, Graph Patch, scheme layout and their limits: document CLI guide · scheme layout · publication recipe.

Documentation

Something got in your way? Open an issue.

Release files for chemvas 0.14.0

For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.

Source distribution (sdist)

Source distribution for chemvas 0.14.0
File Size Uploaded
chemvas-0.14.0.tar.gz 705.9 kB Details

Built distribution (wheel)

Table of built distributions (wheels) for chemvas 0.14.0
File Interpreter ABI Platform
chemvas-0.14.0-py3-none-any.whl Python 3 none any Details

Total release size: 1.6 MB

Release files / chemvas-0.14.0.tar.gz

Download URL chemvas-0.14.0.tar.gz
Size 705.9 kB
Tags Source
SHA-256 checksum
How to use checksums
0beaac3c11f47d15d71e29c89c6f6a2273c5a99f0b93cf142aca5df34f931a11
BLAKE2b-256 checksum
How to use checksums
e9f7d42d0554d890c84712182e1e2e9dab71f30633fff489feb81b8897eb53d1
Upload date
Uploaded using Trusted Publishing?
What is trusted publishing?
Yes
Uploaded via twine/7.0.0 CPython/3.13.14

Provenance

Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.

PyPI Publish Attestation

PyPI verified that this artifact, at this checksum, originated from the publisher listed below.

Signed by GitHub Actions, verified by PyPI on Sep 13, 2026.

Transparency log

Release files / chemvas-0.14.0-py3-none-any.whl

Download URL chemvas-0.14.0-py3-none-any.whl
Size 876.3 kB
Tags Python 3
SHA-256 checksum
How to use checksums
4562e3031c9859ffc2cac3b4c49eab3996e92d933d0838326e3f970740a42cbf
BLAKE2b-256 checksum
How to use checksums
e97d4499ae3a1bff1a4ac0fe08ec550be7e2ac83a7b3c7a374631c0f5f114511
Upload date
Uploaded using Trusted Publishing?
What is trusted publishing?
Yes
Uploaded via twine/7.0.0 CPython/3.13.14

Provenance

Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.

PyPI Publish Attestation

PyPI verified that this artifact, at this checksum, originated from the publisher listed below.

Signed by GitHub Actions, verified by PyPI on Sep 13, 2026.

Transparency log

Release history Release notifications | RSS feed

0.20.0

2 release files

0.19.0

2 release files

0.18.0

2 release files

0.17.1

2 release files

0.17.0

2 release files

0.16.0

2 release files

0.15.0

2 release files

0.14.1

2 release files

This release

0.14.0 This release

2 release files

0.13.0

2 release files

0.12.0

2 release files

0.11.0

2 release files

0.9.0

2 release files

0.8.4

2 release files

0.8.3

2 release files

0.8.2

2 release files

0.8.1

2 release files

0.8.0

2 release files

0.7.0

2 release files

0.6.1

2 release files

0.6.0

2 release files

0.5.1

2 release files

0.5.0

2 release files

0.4.1

2 release files

0.4.0

2 release files

0.3.0

2 release files

0.2.0

2 release files

0.1.0

2 release files

Anthropic, PBC Visionary sponsor Bloomberg Visionary sponsor Hudson River Trading Visionary sponsor Meta Visionary sponsor NVIDIA Visionary sponsor Microsoft Sustainability sponsor Depot Continuous Integration AWS Cloud computing and Security Sponsor Datadog Monitoring Fastly CDN Google Download Analytics Sentry Error logging StatusPage Status page