ryu-monitors

Website monitors for Ryu — price / stock / keyword / content-diff / uptime watches with cross-device notification fan-out.

The public home of ryu-monitors. Source, builds, and releases live here — binaries for every platform are attached to each release.

This tree is generated from the Ryu monorepo, so commits pushed here directly are replaced on the next sync. Pull requests are welcome — open them here and they are ported into the monorepo, then flow back out. Ryu as a whole: https://github.com/amajorai/ryu

Install

• Binary: ryu-monitors from the Ryu releases.
• Crate: cargo install ryu-monitors.

License

Apache-2.0 — see LICENSE.

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Monitors

Website watches. A monitor watches a URL on a schedule and alerts when something changes: the site goes down, a keyword appears/disappears, the page content changes, a price crosses a threshold, or an item comes in/out of stock. Each check fetches the page (plain HTTP or the Spider crawler), extracts the watched signal, and compares it against the latest snapshot — the cross-run state that makes a monitor more than a one-shot fetch. Alerts fan out cross-device.

Parts

• backend/ (ryu-monitors) — an extracted Core capability crate: the check engine, the SQLite MonitorStore, and the /api/monitors/* HTTP surface. Now served OUT-OF-PROCESS by the ryu-monitors bin ([[bin]], kind:local, public_mount, RYU_MONITORS_BIN/RYU_MONITORS_PORT, default :8003); Core links zero monitor code (no path-dep). Its scheduler-coupling (check run + backing-job reconcile) reaches the sidecar over loopback via apps/core/src/monitors_client.rs, and the sidecar reaches BACK via two ext-bearer host callbacks (Spider fetch + alert fan-out). The shared notification-delivery store no longer lives here — it was extracted to the kernel crate ryu-notify + apps/core/src/notify/ (see the repo root); the sidecar shares only the dep-light ryu-notify wire types. Remaining cross-cutting calls are inverted through the MonitorsHost trait, so the crate has zero dependency on apps/core.
• ui/ (@ryu/monitors-app) — the companion surface: a React app built to one self-contained HTML via vite-plugin-singlefile. Full-page Companion (Path B, ui_format: "html").

Manifest

• id com.ryu.monitors · companion Monitors (icon radar).
• grant monitors:crud — the bridge capability the UI drives /api/monitors/* through.

Surface

/api/monitors (list/create) · per-monitor run, snapshots, alerts · alerts + alerts/stream (SSE) + alerts/:id/ack · push-tokens (Expo device registration).

Swap seam

Check type and fetch backend are both extensible enums routed through one engine; timing reuses Core's scheduler (JobTarget::Monitor). Notification targets (webhook / Telegram / Expo push / BYO SMTP email) are per-monitor, none hardcoded.