EXACT-Rust

A Rust port of EXACT (annotation tool for microscopy images): one binary plus PostgreSQL, a new React front end, and the same REST interface for exact-sync and ML workers. Work in progress.

The server runs against the existing EXACT (Django) database: no schema change except additive tables, so Django can be rolled back at any time. The plan, decisions, measurements and the status of every phase are in PLAN.md.

Documentation: docs/ (published with GitHub Pages: user guide, shortcuts, administration, API, installation).

Speed

The numbers

Median response time in milliseconds (lower is better), one request at a time, the first request of each series left out:

Request	EXACT (Django), production	exact-rust, beta	faster
Image sets · Basic auth	694	44	16×
Teams · Basic auth	732	48	15×
Images, 100 · Basic auth	649	80	8.1×
Image sets · session	162	54	3.0×
Teams · session	184	33	5.5×
Images, 100 · session	138	74	1.9×
Slide information (DeepZoom)	96	54	1.8×
Full-resolution tile	109	45	2.4×
Low-resolution tile	135	52	2.6×
Thumbnail	111	84	1.3×

How this was measured (tests/perf/compare_servers.py; the picture is drawn by tests/perf/render_chart.py): the same read-only requests against the old EXACT on its production server and exact-rust on a copy of the same data (24,169 images, 1.4 million annotations), one request at a time, the two servers alternating, with an ordinary member account on each. Basic auth is what exact-sync and workers use (Django checks the password on every request, which is most of its time there); session is what the browser uses after logging in. The slide requests are the DeepZoom descriptor, a tile and the thumbnail of 11 images in 6 formats. Caveats: measured over home wifi, so differences below about 50 ms are noise; the two accounts differ by one team; production serves real users meanwhile. Not in the picture: loading all 45,000 annotations of one image at once (the call exact-sync uses; Django had not answered after three minutes) and many parallel clients: both are in the script and need a quiet server.

Status

Area	State
Auth: password (all Django hash formats), tokens, sessions, passkeys (server side), invitations, impersonation (API)	done
REST: /api/v1 byte-compatible with EXACT incl. writes and the legacy endpoints of exact-sync; /api/v2 for the new UI	done
Slides: OpenSlide formats, TIFF/BigTIFF, OME-TIFF z-stacks, NIfTI/DICOM (three-plane view), MKT, MP4/AVI, CZI/VSI (helper)	done; iSyntax dropped
Pyramid repair, level registration, image registration (manual and by worker plugins), job queue	done
Front end: image sets, uploads, viewer with annotation tools and polygon operations, crops, export, registration, jobs, administration	done
Deployment: Dockerfile, compose, systemd units, runbook (docs/DEPLOY.md)	beta on a copy of production in progress

Layout

• crates/exact-core config, errors - exact-db queries and additive migrations - exact-auth hashes, tokens, WebAuthn
• crates/exact-wsi slide readers, DeepZoom tiles, TIFF reader/writer, pyramid repair and registration
• crates/exact-api HTTP layer (compat/ = v1/legacy for exact-sync, v2/, slides, repair) - exact-server, exact-cli
• frontend/ React + TypeScript + Vite; helpers/slideio_helper.py reads CZI/VSI/DICOM through slideio
• tests/conformance replays recorded responses of the reference EXACT against this server; tests/perf, reference/ (reference Django setup)

Run

make ui                       # build the front end (frontend/dist, served by the binary)
cargo build -p exact-server   # needs libopenslide, ffmpeg (libav*) and libclang to build
SQL_DATABASE=exact SQL_USER=... SQL_PASSWORD=... IMAGE_PATH=/path/to/images EXACT_LISTEN=127.0.0.1:8002 target/debug/exact-server

Configuration uses EXACT's environment variable names (SQL_*, IMAGE_PATH, FIDO_SERVER_ID, ...); EXACT_CACHE_DIR holds thumbnails, SLIDEIO_PYTHON / SLIDEIO_HELPER select the slideio helper, EXACT_STATIC_DIR the front end.

Tests

make verify restores a scratch database from a backup of an EXACT database (backups/, not in the repository: create it with pg_dump -Fc of a local EXACT, see scripts/restore-backup.sh), starts the reference Django and this server and runs unit tests, conformance (Django vs. recorded responses vs. Rust), exact-sync, the v2 suites and a schema-sync check (make schema-sync). make e2e runs the browser smoke test (system Chrome); make e2e-repair the repair flow on a scratch copy.

License

MIT, like EXACT.