Files
wordcraft/README.md
T
663904a2e2 Import Word 97-2003 .doc files (#28) (#145)
* D0+D1: open Word 97-2003 .doc — container, FIB, piece table text (#28)

New wordcraft-docbin crate (L2) reads the OLE2 container via the cfb
crate (MIT) and parses the FIB and piece table from the [MS-DOC]
specification: text pieces decode as UTF-16LE or Windows-1252 (table
moved to wordcraft-doc::encoding), subdocument CP ranges, and Word's
special characters map to the model's (tabs, breaks, hyphens). .doc/.dot
registered in OPEN_EXTS and the I/O dispatch. Encrypted and Word 6/95
files give clear errors; every length is checked and proptest
truncation/flips never panic.

* D2: .doc formatting — stylesheet, fonts, CHPX/PAPX FKPs, sprms (#28)

Sprm decoder with operand-size rules (incl. sprmTDefTable/sprmPChgTabs
exceptions and the Prm0 isprm table), bin tables + ChpxFkp/PapxFkp page
lookup, STSH styles (StdfBase layout validated against real Word files:
bchUpe == cbStd, sti 0 = Normal) and the SttbfFfn font table in both
extended and self-delimiting flavours. The CP walk now splits runs on
formatting changes and resolves paragraph styles: bold/italic/strike/
underline/caps/hidden, colours (Ico palette + COLORREF), half-point
sizes, super/subscript, fonts, highlights; alignment, indents, spacing,
keep options, outline levels. Unknown sprms are skipped leniently;
an env-gated corpus test opens real files (styles + text asserted).

* D3: .doc structure — sections, headers/footers, tables, lists (#28)

- Sections: PlcfSed/Sepx with 16-bit measurement sprms (sprmSXaPage & co),
  explicit sprmSBOrientation with a width/height fallback; even/odd/first
  header and footer stories from Plcfhdd become document parts.
- Tables: sprmTDefTable grids (operand length fixed to cb+1 per the spec),
  horizontal merges (sprmTMerge), vertical merges (sprmTVertMerge), cell
  shading (sprmTSetShd / sprmTDefTableShd80), cell widths, valign, row
  height/header/cant-split, and table borders (sprmTTableBorders80 Brc80s).
- Lists: PlfLst (LSTF + appended LVLs) and PlfLfo (LFO + LFOLVL overrides)
  resolved into the numbering model; sprmPIlvl/sprmPIlfo mark paragraphs.
- Combined fixture (intro + table + list + 2 sections + header) round-trips
  through Document JSON; hostile proptests now mutate the structured fixture.

* D4: .doc notes, fields, bookmarks and inline pictures (#28)

- Footnotes/endnotes: PlcffndRef/PlcfEndRef reference CPs paired with the
  PlcffndTxt/PlcfEndTxt story ranges; each story walks into a Footnote or
  Endnote part and the 0x02 anchor becomes a NoteRef object.
- Fields: 0x13/0x14/0x15 state machine in the walker — instruction text is
  hidden, the cached result kept; HYPERLINK fields keep their result as
  linked runs, everything else becomes one Field object.
- Bookmarks: SttbfBkmk names + Plcfbkf/Plcfbkl CPs become BookmarkStart/
  BookmarkEnd objects at their anchors.
- Pictures: sprmCPicLocation points into the Data stream; the PICF header
  gives the display size (dxaGoal/dyaGoal scaled by mx/my) and the payload
  is format-sniffed (PNG/JPEG/GIF/BMP; metafiles are dropped with a warn).
- Hostile proptests now truncate/flip a fixture with all of the above.

* D5: .doc import hardening, caps and roadmap (#28)

- Cap inline pictures at 5 000 per document.
- Engine test: .doc/.dot bytes dispatch through the Word 97-2003 reader
  (garbage must error, never panic or open empty).
- ROADMAP: Word 97-2003 import row (60% — text, formatting, styles,
  sections, headers/footers, tables, lists, notes, fields, bookmarks,
  raster pictures).

Real-corpus validation stays opt-in: WORDCRAFT_DOCBIN_FIXTURES=<dir>
cargo test -p wordcraft-docbin corpus_files_open.

* Corpus fixes: compressed-piece FC space, PAPX query point, none-level labels (#28)

Validated against two real files (kept locally under plan/word/fixtures,
gitignored): a 1 MB Lorem-ipsum sample and a 2003 styles/lists/table
sample.

- FKP bin tables and pages address the WordDocument stream in true byte
  offsets; a compressed piece stores its base fc doubled (byte = fc/2),
  so fc_of_cp now unwinds the doubling. Before, every PAPX/CHPX lookup in
  compressed (cp1252) files landed on the wrong entry — tables collapsed
  to one row, lists and heading styles were lost.
- The paragraph-properties query now uses the paragraph mark's own FC
  (inside the paragraph) instead of the FC after it, which picked up the
  next paragraph's FKP entry.
- Fixture papx entries re-keyed to paragraph-start CPs, the real rgfc
  convention.
- Counters::next_label returns nothing for NumFormat::None levels (Word's
  numFmt none shows no label; also fixes a latent docx-reader case).
- Symbol/Wingdings bullet chars map to Unicode glyphs (• ▪ ○ ●).

With this, both corpus files render headings, styles, nested and numbered
lists, the tables and the PAGE field correctly; metafile-wrapped images
and OLE objects stay dropped by policy (logged).

* docbin: bound the text walk by real text; dedupe and cap pictures (#28)

Hostile CP numbers no longer drive the work:
- header/footnote/endnote story ranges from the Table stream are clamped to their
  subdocument (ccpHdd/ccpFtn/ccpEdn) with checked base additions, and every walk stops at
  the last piece's CP; a story spanning [0, 4e9) used to push billions of U+FFFD;
- characters are found by binary search over the pieces (PieceTable::char_at), and an
  unreadable stretch (gap, truncated or out-of-stream piece) is skipped in one step rather
  than one U+FFFD per CP; the old per-character scan was O(chars x pieces);
- the piece CPs are made non-decreasing at parse, so inverted pieces are empty and binary
  search stays sound; surrogate pairs now decode;
- note references are looked up by binary search; the style's CharProps is borrowed, not
  cloned, per character;
- pictures are interned by fc_pic (5000 anchors on one picture share one media entry and
  one copy) and the bytes copied per document are capped at 256 MB.

Each fix has a crafted-bytes regression test; against the previous code the story,
piece-claim, last-piece and many-pieces tests hang (killed at 60 s) and the shared
picture test copies the picture once per anchor (80 GB).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* docbin: checked offset arithmetic in lists, sections and table rows (#28)

- list.rs: PlfLst/PlfLfo/LVL offsets (at + 2 + cLst*28, at + 4 + lfoMac*16, off += len,
  ...) saturate, which matters on 32-bit targets (wasm32) where fc + n can overflow usize;
  the LFO override path no longer indexes abstracts directly.
- sections.rs: the Sepx range (fc_sepx + 2 + cb) is checked; Plcfhdd is read only as far
  as the stories a capped section count can use (it used to reserve lcb/4 entries).
- table.rs: sprmTDyaRowHeight = i16::MIN negated in i16 (overflow panic in debug builds);
  now -(v as f32).

Regression tests: the row height test failed before (overflow panic with debug assertions, a 0 pt height without); the list test pins the saturating
offsets (it only overflowed on 32-bit targets).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Format the merged OPEN_EXTS list

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

---------

Co-authored-by: Brandon Thomas <echelon@gmail.com>
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-10 08:36:38 -04:00

22 KiB

ArtCraft

WordCraft

Writing and document design; an open-source, clean-room reimplementation of Microsoft Word, rebuilt in pure Rust.

A fast, open-source word processor with the Word workflow you already know: the ribbon, styles, tables, track changes, references and mail merge. It reads and writes .docx, runs natively on macOS, Windows, Linux and BSD, and in the browser via WebAssembly.
By the ArtCraft team.

Written in Rust Runs on macOS, Windows, Linux, BSD and the web License: MIT OR Apache-2.0 Agent-drivable over MCP

Join the ArtCraft community on Discord

WordCraft on getartcraft.com · ArtCraft · All Crafting Apps


WordCraft with the Home tab of the ribbon open over a two-page document titled The Open Studio Handbook. The Navigation pane on the left lists the document's headings, the Styles gallery shows live previews of Normal, Heading 1, Title and Subtitle, and a word in the first paragraph is selected.
The Open Studio Handbook, WordCraft's built-in sample: the ribbon, live Styles gallery, rulers and the Navigation pane.

Note

ArtCraft is a community of artists from all walks of life. Painters, photographers, filmmakers, illustrators, designers, animators, hobbyists, and people who picked up a pencil last week. If you make things, you're one of us. Come say hi on Discord.

A tour · Why WordCraft · What works today · Quick start · For agents · Architecture · Roadmap · Downloads · The Crafting Apps · License and credits

A tour

Every screenshot below is WordCraft itself, rendered offscreen by its own UI test harness (cargo run -p wordcraft-ui-egui --example ui_shot).

The Review tab with Track Changes on: the word forty is inserted in magenta and thirty struck through; three commented phrases are shaded and joined by dashed leader lines to comment balloons in a grey markup area to the right of the page

Review. Track changes, comment balloons in the margin, accept and reject, spelling and grammar as you type.

The References tab with two pages side by side: a table of contents with dotted leaders and page numbers on page one, and a styled table, numbered list and hyperlink on page two

References. Tables of contents, footnotes, citations in APA, MLA, Chicago or IEEE, index and captions.

The Design tab showing style-set previews; the document is set in a serif theme with plum headings underlined by thin rules and a pale diagonal DRAFT watermark behind the text

Design. Themes, style sets, paragraph spacing, watermarks, page colour and borders.

WordCraft in dark mode with the Insert tab open and formatting marks shown: pilcrows at paragraph ends and dots for spaces

Dark mode with formatting marks, and the Insert tab: tables, pictures, shapes, links, headers, footers, fields and symbols.

The Layout tab at 80% zoom: the first paragraph opens with a three-line drop cap E, a dark blue circle sits beside the second section with its paragraph wrapping around it and hyphenating art-ist at the line end, every line is numbered in the left margin and a thin blue border surrounds the page

Layout. Drop caps, text wrapping around pictures and shapes, automatic hyphenation, line numbers and page borders.

The File tab start page with a Good morning greeting, thumbnails of the Blank document, Studio handbook, Letter, Résumé and Report templates, and a list of recent documents

File. Start from a template, open recent documents, edit properties, export to PDF and other formats.

Why WordCraft

  • Familiar. Word's ribbon tabs, groups, shortcuts and behaviour: Enter continues a list, Tab demotes it, Ctrl/⌘+B bolds the word under the caret, the Styles gallery previews styles live, F4 repeats, F7 checks spelling, F8 extends the selection.
  • Your files. Opens and saves .docx (OOXML), and also .odt, .rtf, .html, .md, .tex (LaTeX), .txt; opens Word 97-2003 .doc; exports PDF with real, selectable text, links and bookmarks.
  • Fast. Paragraph layout is cached, so typing in a 188-page document re-lays it out in about 1.4 ms; pages render on demand.
  • Everywhere. One Rust codebase for macOS, Windows, Linux, BSD and the web. No Electron, no Tauri: native egui on the GPU.
  • Built for agents. Every action is a command with an id. The same 389 commands drive the ribbon, keyboard shortcuts, the command search, a command-line tool, a JSON control channel and an MCP server.
  • Private. Spelling, grammar and everything else work offline.
  • Open. MIT OR Apache-2.0. Clean-room: built from public specifications and observation, with every asset original or openly licensed.

What works today

Area Highlights
Writing Fast typing with IME, smart quotes, AutoCorrect, list autoformat (* , 1. ), dashes; word, sentence, paragraph selection; drag-select; clipboard with formatting; undo/redo; find and replace with regex
Formatting Fonts, sizes, bold/italic/underline styles, strike, sub/superscript, caps, highlight, colours, character spacing, Format Painter, Change Case, Clear Formatting
Paragraphs Alignment, indents (draggable on the ruler), spacing, line spacing, tabs with leaders, borders, shading, keep with next, widow/orphan control
Styles Built-in style set, live gallery, Styles pane, create/modify/update styles, style sets, themes
Lists Bullets, numbering, multilevel, restart, set value, custom formats
Tables Insert by grid, merge/split, styles with banded rows, borders, shading, header rows repeated across pages, rows that split across pages, sort, formulas, text ↔ table
Pages Margins, orientation, size, columns, page/column/section breaks, headers and footers (first page, odd/even), page numbers, watermark, page borders, line numbers, vertical alignment, drop caps, automatic hyphenation
Objects Pictures (resize, crop, recolour, brightness/contrast, transparency, background removal, picture styles, rotate), shapes, text boxes, floating position with text wrapping (square, top and bottom, behind or in front of text)
References Table of contents, footnotes and endnotes, citations and bibliography (APA, MLA, Chicago, IEEE), captions, table of figures, cross-references, index, table of authorities
Review Spelling and grammar with suggestions, thesaurus, word count, comments in margin balloons or a pane, track changes, accept/reject, compare documents, restrict editing, accessibility checker, document inspector
Mailings Mail merge from CSV, merge fields, address block, greeting line, rules, preview, finish to a document; envelopes and labels
View Print layout, web layout, draft, read mode, focus, zoom, one/multiple pages, page width, Navigation pane, rulers, gridlines, dark mode; interface in English, 简体中文, 繁體中文, 日本語, Português (Brasil), Español or Українська (follows the system language by default)
Files .docx read/write (opens in Word), Word 97-2003 .doc import, PDF export, .odt, .rtf, .html, .md, .tex, .txt import/export, page images

The honest picture, area by area, is in ROADMAP.md and the generated feature parity report.

Quick start

git clone https://github.com/storytold/wordcraft
cd wordcraft
cargo run --release -p wordcraft -- --sample        # the desktop app with the sample document
cargo run --release -p wordcraft -- report.docx     # open a document

Command line:

wordcraft-cli convert report.docx report.pdf        # docx, pdf, odt, rtf, html, md, tex, txt, png
wordcraft-cli text report.docx                      # plain text
wordcraft-cli inspect report.docx                   # structure as JSON
wordcraft-cli run --template sample \
  --cmd 'select.text={"text":"Membership"}' --cmd format.bold --save out.docx

Web: cd apps/wordcraft-web && trunk serve, then open http://127.0.0.1:8771/?sample.

For agents: CLI and MCP

WordCraft was designed to be driven by people and by AI agents.

claude mcp add wordcraft -- wordcraft-cli mcp                  # headless documents
wordcraft --control 7981 &                                     # or drive the running app…
claude mcp add wordcraft-app -- wordcraft-cli mcp --connect 127.0.0.1:7981

Tools include list_commands, execute, batch, type_text, select_text, inspect_document, render_page, save_document, and, with a running app, screenshot, click and key. Agents can check their work through inspect_document without screenshots. See docs/mcp.md and the control protocol. Macros record any sequence of commands and play it back (tools.recordMacro, tools.macros).

Logs

The desktop app writes its log records to standard error and to logs/wordcraft.log next to its preferences: on Linux $XDG_CONFIG_HOME/wordcraft/logs/ (by default ~/.config/wordcraft/logs/), on macOS ~/Library/Application Support/WordCraft/logs/, on Windows %APPDATA%\WordCraft\logs\. A start from a desktop menu or the Dock has no terminal, so this file is what to attach to a bug report: unreadable parts of a .docx, pictures or fonts a PDF export had to leave out and panics the command guard recovered from land there. Each launch moves the previous log to wordcraft.1.log (and that one to wordcraft.2.log), so the log of a run that crashed survives the next start; a log stops growing at 16 MiB. --version writes no file, and runs with WORDCRAFT_NO_PREFS (agents' test runs) log to standard error only. Document text is never logged; a panic message leaves out the text it quotes.

By default WordCraft's own crates log at info and everything else at warn. RUST_LOG replaces that with env_logger-style directives, for example RUST_LOG=debug, RUST_LOG=warn,wordcraft_docx=trace or RUST_LOG=info,wgpu_core=warn; a directive ending in * covers every target starting with it (wordcraft*=debug). The logger is apps/wordcraft/src/logging.rs.

Architecture

Layer Crate Job
L0 wordcraft-geom units and measurements
L1 wordcraft-doc, wordcraft-fonts, wordcraft-proof document model and editing; fonts and shaping; spelling, grammar, hyphenation
L2 wordcraft-layout, wordcraft-docx, wordcraft-formats line breaking, pagination, tables, notes, hit testing; OOXML; ODT/RTF/HTML/Markdown/TXT
L3 wordcraft-render, wordcraft-pdf rasteriser (vello_cpu); PDF (krilla)
L4 wordcraft-engine session, undo, 389 commands, Word feature catalog
L5 wordcraft-mcp MCP server
L6 wordcraft-ui-egui the Word-style front end (swappable)
apps wordcraft, wordcraft-cli, wordcraft-web desktop, command line, browser

cargo xtask ci runs formatting, clippy, ~250 tests, the asset-attribution check, the layering check and the wasm build. Contributor and agent instructions: AGENTS.md.

Roadmap

WordCraft covers 87% of Word's ribbon features with commands today; counting depth and fidelity, we estimate about 62% of real feature parity. An alpha for everyday writing is close: the remaining work is mostly testing against real-world .docx files, native printing and the first signed builds. Charts, SmartArt, the equation editor and the Draw tab come after. Details and estimates: ROADMAP.md.

Downloads

Download WordCraft from GitHub: the latest release has every build listed below, and all releases has earlier versions and their notes. <ver> in the file names is the version number, and SHA256SUMS.txt lists a checksum for every file.

Windows

Build Installer Portable
x64 (64-bit Intel/AMD) wordcraft-<ver>-windows-x64.msi wordcraft-<ver>-windows-x64-portable.zip
arm64 (Snapdragon and other ARM PCs) wordcraft-<ver>-windows-arm64.msi wordcraft-<ver>-windows-arm64-portable.zip
x86 (32-bit) wordcraft-<ver>-windows-x86.msi wordcraft-<ver>-windows-x86-portable.zip

Installers and executables are code-signed.

If the app doesn't open on Windows: the desktop app initializes only DirectX 12 by default. Letting wgpu also create an OpenGL instance can crash some graphics drivers (AMD's atio6axx.dll) before the window appears, so the app would flash in Task Manager and quit. WGPU_BACKEND overrides the default for troubleshooting (for example dx12 or vulkan). In PowerShell, from the folder containing the executable:

$env:WGPU_BACKEND = "vulkan"
& .\wordcraft.exe
Remove-Item Env:WGPU_BACKEND                     # restore the default for later launches

An explicit gl override can bring the driver crash back on affected systems. The macOS, Linux and web backend defaults are unchanged.

macOS

Build File Notes
App, universal (Apple silicon + Intel) wordcraft-<ver>-macos-universal.dmg Signed and notarized
Command-line tool, universal wordcraft-cli-<ver>-macos-universal.zip Signed and notarized

Linux

Format x86_64 aarch64 (ARM64) Notes
AppImage wordcraft-<ver>-linux-x86_64.AppImage wordcraft-<ver>-linux-aarch64.AppImage Runs anywhere; updates itself with AppImageUpdate (.zsync files)
Flatpak wordcraft-<ver>-linux-x86_64.flatpak wordcraft-<ver>-linux-aarch64.flatpak Sandboxed; flatpak install --user <file>
Debian/Ubuntu wordcraft-<ver>-linux-x86_64.deb wordcraft-<ver>-linux-aarch64.deb
Fedora/RHEL/openSUSE wordcraft-<ver>-linux-x86_64.rpm wordcraft-<ver>-linux-aarch64.rpm
Tarball wordcraft-<ver>-linux-x86_64.tar.gz wordcraft-<ver>-linux-aarch64.tar.gz Unpack anywhere

FreeBSD

Build File
x86_64 wordcraft-<ver>-freebsd-x86_64.tar.gz

Web (WebAssembly)

Build File Notes
Static site wordcraft-web-<ver>.zip Runs in a modern browser; host it on any static server

The Crafting Apps

WordCraft is one of the Crafting Apps: free, open-source creative tools from the ArtCraft team, each written from scratch in Rust and each able to stand on its own.

App What it's for Code Learn more
PhotoCraft Image editing: layers, masks, type and real PSD files GitHub Website
VectorCraft Vector illustration GitHub Website
FilmCraft Video editing, color and sound GitHub Website
LightCraft Photo library and raw development GitHub Website
PdfCraft Reading, organizing and protecting PDFs GitHub Website
EffectCraft Motion graphics and visual effects GitHub Website
DesignCraft Page layout and publishing GitHub Website
WordCraft Writing and document design · you are here GitHub Website

And ArtCraft itself, our AI image and video studio for artists who want real control.


Join the ArtCraft community on Discord

Come make things with us

Our Discord is where artists of every kind hang out: people who paint, shoot, draw, cut film, set type, and people still figuring out what they like to make. Share what you're working on, ask for help, tell us what's broken, or tell us what you wish these tools could do. Whatever your medium and however long you've been at it, you're welcome here.

discord.gg/artcraft · getartcraft.com · The Crafting Apps · WordCraft

License and credits

WordCraft is dual-licensed under MIT or Apache-2.0, at your option. Copyright (c) 2026 ArtCraft Team and the WordCraft contributors. Required notices are in NOTICE.

Bundled fonts, icons, images and other assets keep their own open licenses; each one is listed with its author, source and license in ATTRIBUTION.md.

The spelling dictionary and hyphenation come from Grady Ward's public-domain Moby Hyphenator II word list. The sample documents and templates are original text written for WordCraft.

The ArtCraft name, wordmark and logos in docs/brand/ are trademarks of the ArtCraft Team and are not covered by this license. They may be used only unmodified, and only as part of this repository and WordCraft, under docs/brand/LICENSE-brand.txt. Forks and modified versions must remove them.

Microsoft and Microsoft Word are trademarks of the Microsoft group of companies. Adobe, Photoshop, Illustrator, Premiere Pro, Lightroom, Acrobat, After Effects and InDesign are trademarks or registered trademarks of Adobe Inc. in the United States and/or other countries. WordCraft is an independent, open-source project and is not affiliated with, sponsored by or endorsed by Microsoft Corporation or Adobe Inc.; these names are used only to describe the workflows it is compatible with.

ArtCraft
Made by the ArtCraft team and community.