Theseus Extensions

Signed over-the-air update endpoint for Theseus's bundled add-ons. Every entry is Ed25519-signed by the Silent Mode operator, verified on the device before install. No cert authority, no app-store gatekeeper.

Available extensions

Currently one bundled add-on ships with a signed update channel. More on the way.

๐Ÿ“ธ Screenshot current 0.2.4

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Ships bundled with Theseus 0.3.21+. Later versions auto-update through this endpoint on the next boot's 30-second poll.
Signed update manifest โ€” SHA-256 verified before install
sha256399a9a3be696aaaa96a1c12c4da0bbae6585efbdc4338a5caabb1769e0f36861

How updates work

Same mechanism a Firefox XPI update uses, cut down to what a name-native browser needs.

  1. Every 30 seconds after boot Theseus fetches updates.json for each installed add-on that declares an updateURL in its manifest.
  2. Each entry carries an Ed25519 signature over silentmode.addon-update-v1|<id>|<version>|<sha256>. Theseus verifies against a small set of operator public keys baked into the build. Unsigned or badly-signed entries are dropped silently.
  3. If a signed version beats what's installed, Theseus downloads the tarball, re-checks its sha256, and stages the new copy under <userData>/addons-updates-staged/<id>-<version>/.
  4. On the next Theseus launch, promoteStagedUpdates moves the staged copy into addons/<id>/. Any prior copy is renamed to addons-backups/<id>-<oldver>-<timestamp>/ so hand-edits survive.
  5. The Settings > Extensions surface (Theseus 0.3.26+) has a Check for updates button and a Pending updates box for on-demand control.

Operator key

The Ed25519 public key baked into Theseus 0.3.19+. Rotation is by adding a new pubkey and shipping a Theseus release that carries both, then a follow-up release removing the old โ€” during the overlap, entries can be signed by either.

732b1263a236b0030383a2376597cfa43c3624b3ca2912a46134f8f2a06e6012

Generated 2026-09-07. Held offline by the Silent Mode operator.

Roadmap

The endpoint is generic โ€” any bundled add-on can advertise an updateURL. Concrete next-steps: