Folio

The open PDF workbench — a clean-room alternative to Adobe Acrobat Pro, written from scratch in pure Rust.
Read, repair, organize, comment, fill, sign and protect PDFs. No account, no telemetry.
Windows · macOS · Linux

Folio is an independent project and is not affiliated with Adobe. "Acrobat" is used only as the reference for which features to build.

Status

Folio is being built in public, stage by stage — see PLAN.md for the full list of Acrobat Pro features and the order they arrive in, and parity/acrobat-features.toml for exactly what works today.

Stage	Scope	State
0	Foundation: PDF engine (lenient parser, repair, filters, writer), verification agent	✅
1	Organize pages + command line, faithful to Acrobat's options (combine, split, extract, insert, replace, rotate, crop, page labels, properties, reduce size, text)	✅
2	Security, faithful to Acrobat: open protected files (RC4 40/128, AES-128/256), Encrypt with Password with every option, Restrictions Summary, permissions enforced	✅
3	Rendering engine — 3a vector graphics ✅ (paths, clipping, colour spaces, functions, transparency, forms); 3b images ✅ (JPEG, JPEG 2000, JBIG2, fax, masks); 3c text ✅ (TrueType, OpenType, CFF, Type 1, Type 3, CID fonts); 3d ✅ shadings, patterns, soft masks, transparency groups, annotations; 3e ✅ export as PNG, JPEG or TIFF with Acrobat's settings; all match Poppler	✅
4	Desktop app	next
5–16	Comments, forms, editing, convert, signatures, redaction, OCR, optimize, PDF/A, tools, print, installers	planned

Try it

git clone https://github.com/zolyy/folio
cd folio
cargo build --release
./target/release/folio info report.pdf
./target/release/folio merge -o all.pdf intro.pdf report.pdf:1-3,7
./target/release/folio split big.pdf --bookmarks
./target/release/folio rotate scan.pdf --direction ccw --subset even -o fixed.pdf
./target/release/folio crop doc.pdf --margins 0.5 --unit in -o cropped.pdf
./target/release/folio labels book.pdf --pages 1-4 --style roman -o book2.pdf
./target/release/folio --json text report.pdf --pages 2-
./target/release/folio encrypt report.pdf --open-password ... --permissions-password ... --changes pages -o locked.pdf
FOLIO_PASSWORD=... ./target/release/folio security locked.pdf
./target/release/folio render report.pdf --pages 1 --dpi 150 -o page1.png
./target/release/folio render report.pdf --format jpeg --quality high --jpeg-mode progressive --dpi 300
./target/release/folio crop scan.pdf --remove-white-margins -o tight.pdf

Run folio --help and folio <command> --help for every option. Each command mirrors an Acrobat Pro dialog; the mapping is in docs/acrobat/organize.md.

How it's built

• folio-core — the PDF object model, a tolerant lexer/parser, cross-reference tables and streams, object streams, incremental updates, rebuild-by-scanning for damaged files, Flate/LZW/ASCII85/ASCIIHex/RunLength with PNG/TIFF predictors, and a writer that always emits a clean, repaired file atomically.
• Never crash. unsafe is forbidden; unwrap/expect/panic! are denied outside tests; every stage closes with an anti-crash gate that runs every operation on tens of thousands of corrupted documents.
• folio-ops — organize pages, combine, split, page labels, document properties (Info + XMP), reduce file size and text extraction, each option matching Acrobat Pro.
• folio-render — the content-stream interpreter, graphics state, colour spaces and PDF functions, rasterised with tiny-skia; checked against Poppler in tests.
• Headless first. Every feature is a folio command with --json output, so scripts and AI agents can drive it.

Contributing

Contributions from people and AI agents are welcome. Everything passes the same verification agent — cargo xtask ci locally and in CI, DCO sign-off, a PR checklist, and an automated review against AGENTS.md. Start with CONTRIBUTING.md.

License

Dual-licensed under MIT or Apache-2.0, at your option.