reHydrate

A privacy-respecting desktop app for managing documents on a reMarkable 2 over USB. No cloud, no telemetry; the app talks only to a tablet plugged into your computer.

The library lives in a single self-contained directory you control: every distinct file is stored once by content hash, every change to every document is captured as a new version, and any past version can be restored to the device or exported to disk.

Status

v1.0.2 — patch release on the v1.0 line. macOS (Apple Silicon) only. Bundles ship unsigned; see Installing below for the Gatekeeper right-click dance on first launch. Working features:

• Two-way sync (pull + push) over USB-SSH, with progress streamed live.
• Content-addressed blob store, full version history, restore-any-version.
• Archive with restore (soft-delete; the tablet only sees the deletion on the next sync).
• Import PDFs and EPUBs from disk; they upload to the tablet on the next sync.
• Folder organisation, drag-and-drop moves, multi-select with Cmd-click + Shift-click + a selection toolbar.
• Library health (Verify) and orphan-blob cleanup (Clean up unused files) with confirmation.
• Quick Look (Space), command palette (⌘K), keyboard navigation, search.
• Multi-library support: switch between per-tablet libraries from the toolbar without restarting.
• Notebook OCR via Ollama. Convert a handwritten notebook to text with a vision-language model running on your own machine (or a GPU box on your LAN). No cloud OCR; no transcripts leave your network unless you explicitly publish them.
• Publish transcripts to Ghost or WordPress as drafts. The credential entry, host-pinned HTTP client, and explicit user trigger mean transcripts never reach anywhere you didn't configure.

Architecture notes are in docs/architecture.md; release notes are in CHANGELOG.md; threat model and security posture in SECURITY.md.

Installing

reHydrate ships pre-built bundles on the GitHub Releases page for macOS (Apple Silicon, 11.0+). Intel Macs, Windows, and Linux are not currently shipped as binaries — building from source works on all three; see Building below.

v1.0 bundles are unsigned — code-signing is on the roadmap for v1.1. Until then, macOS warns on first launch:

1. Download reHydrate_<version>_aarch64.dmg from the latest release.
2. (Optional but recommended) Verify the download against SHA256SUMS, which is also attached to the release: shasum -a 256 reHydrate_*.dmg should match the corresponding line in SHA256SUMS.
3. Right-click the .dmg (or Control-click) and choose Open. Don't double-click — Gatekeeper will reject the unsigned bundle.
4. Drag reHydrate to /Applications.
5. The first time you launch the app, right-click reHydrate in /Applications and choose Open. Confirm the "unidentified developer" warning. After this one-time bypass, normal double-click works.
6. The first time you connect a tablet, macOS will prompt for Local Network access — the tablet shows up at 10.11.99.1 over USB-Ethernet, and macOS classes that as local network. Allow it. If you dismissed the prompt, re-enable reHydrate under System Settings → Privacy & Security → Local Network.

Compatibility

• Host: macOS 11.0+ on Apple Silicon (M1 / M2 / M3 / M4). Intel Macs are not shipped as binaries; building from source on Intel works but is not part of CI. Linux / Windows builds from source — no bundles.
• Tablet: the reMarkable 2 on stock firmware (xochitl) is the only tablet reHydrate has been directly tested against so far.
• OCR (optional): Ollama 0.6+ on the same machine or a reachable LAN host, with at least one vision-language model pulled (default qwen3.5:4b, ~3.4 GB on disk). Without Ollama every other feature still works; only "Convert to text…" is disabled.

If you're on a model / firmware combination not in the list above, sync will most likely work but is not part of the test matrix — please file an issue from the in-app About dialog if you hit a problem so the matrix can grow.

Known limitations

• No auto-update. See Updates below.
• Unsigned, un-notarized macOS bundle — first launch needs a right-click → Open (see Installing).
• OCR partial-failure handling: if individual pages fail (Ollama returns 5xx for those pages) the transcript is committed with inline *[Page N: transcription failed — re-run OCR to retry]* placeholders and a header note. If every page fails the transcript is not committed and the run surfaces the failure to the user instead.

Updates

reHydrate does not auto-update. Subscribe to the GitHub repo's release feed, or check the Releases page from the in-app About dialog (Help → About reHydrate → Check for updates). Security fixes will be called out in the release notes.

Optical character recognition

reHydrate doesn't ship an OCR model — it talks to an Ollama daemon you run yourself. That keeps the bundle small, lets you swap models without an app update, and means every byte of your handwriting stays on hardware you control.

Setup, in a fresh terminal:

# Install Ollama (or grab the installer from ollama.com/download).
brew install ollama

# Pull a vision-language model. Pick one:
ollama pull qwen3.5:4b       # default — ~3.4 GB, runs on 8 GB GPUs / M-series
ollama pull qwen3.5:9b       # sharper at cursive + math — ~6.6 GB

# Start the daemon (background service on macOS).

Then open reHydrate, click the gear icon → Settings → Ollama, hit Test connection, and Save. From there, "Convert to text…" in any document's three-dot menu starts a transcription. Progress is shown in a floating chip; results land in the Transcript drawer with Save-as-.txt / Save-as-.md and Publish actions.

Pointing reHydrate at a different host is supported — useful if you keep a small machine on your LAN just for inference. The host must be reachable by name (give the box an mDNS / DNS entry, e.g. https://ollama.lan:11434, and terminate TLS in front of Ollama) because reHydrate refuses plain HTTP to anything other than localhost and refuses HTTPS to literal private IPs — both close SSRF-shaped paths. Every request is host-pinned and refuses redirects (see SECURITY.md).

Publishing transcripts

Transcripts can be POSTed directly into Ghost or WordPress as drafts:

• Ghost: Settings → Integrations → Custom integration; copy the Admin API key (the <id>:<hex> form) and the site URL into reHydrate's Settings → Publishing tab.
• WordPress: Users → Profile → Application Passwords (WP 5.6+); copy the password, paste alongside the site URL and your username.

Credentials live in your OS keychain. reHydrate only contacts the host you entered — never anywhere else.

Stack

• Core: Rust workspace (crates/rehydrate-core, rehydrate-device, rehydrate-sync, rehydrate-app, rehydrate-ocr, rehydrate-publish, rm-parser)
• UI: Tauri 2 + Vite + React + TypeScript (ui/)
• Transport: SSH/SFTP over USB-ethernet (10.11.99.1)

Building

Prerequisites: Rust stable (≥ 1.82), Node.js 20.19+ or 22.12+, npm, and (for bundle builds) the Tauri CLI:

cargo install tauri-cli --version "^2.0.0"

./build.sh is the one-liner. By default it produces a release .dmg + .app under target/aarch64-apple-darwin/release/bundle/ — the same artefact the GitHub release workflow attaches to a tag.

./build.sh             # build the .dmg + .app bundle (release)
./build.sh --open      # ... and reveal the bundle in Finder
./build.sh --install   # ... and copy the .app to /Applications
./build.sh --dev       # quick iteration: cargo run -p rehydrate-app --release

For day-to-day dev with UI hot reload, prefer cargo tauri dev (Vite serves the UI directly, no static bundle needed).

The bundle path requires an Apple Silicon host and passes --no-default-features to strip the in-app webview inspector — the release workflow does the same. See PACKAGING.md for the full rationale and the manual cargo tauri build invocation.

Testing against a real reMarkable

Two integration tests run against a tablet plugged in over USB. Both are read-only.

# Capture password: tablet → Settings → Help → Copyrights and licenses
MARGINALIA_RM_PASSWORD='...' \
    cargo test -p rehydrate-device --features ssh \
    --test ssh_smoke -- --ignored --nocapture

MARGINALIA_RM_PASSWORD='...' \
    cargo test -p rehydrate-sync \
    --test full_pull_smoke -- --ignored --nocapture

Packaging notes (signing, notarization, release workflow) are in PACKAGING.md.

Layout

crates/
  rm-parser/         reMarkable v6 binary file parser
  rehydrate-core/    blob store, manifests, version log
  rehydrate-device/  device transport: trait + fake + ssh
  rehydrate-sync/    sync engine
  rehydrate-ocr/     Ollama client + page rendering
  rehydrate-publish/ Ghost / WordPress upload
  rehydrate-app/     Tauri binary
ui/                  React frontend
docs/                architecture notes + landing page

Contributing

Bug reports, feature ideas, and pull requests are all welcome. See CONTRIBUTING.md for dev environment setup, the test/lint commands CI runs, commit conventions, and how to file a good bug. The project follows the Contributor Covenant — be kind, assume good faith. Security issues go through the private advisory form, not public issues; see SECURITY.md for details.

Licence

reHydrate is dual-licensed under either of:

• MIT licence (summary)
• Apache License, Version 2.0 (summary)

at your option. Pick whichever fits your downstream use; you don't need to do anything special either way.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in reHydrate by you, as defined in the Apache-2.0 licence, shall be dual-licensed as above, without any additional terms or conditions.

The name reHydrate is reserved as a project identifier. You may fork the code under the licences above, but please rename the fork if you redistribute it so users don't confuse forks with the upstream project.