Site-centric monitoring
Group HTTP, SSL, DNS, TCP, and heartbeat checks under the service they protect.
Alon SystemsAlon SentinelAGPL v3Rust BackendPostgreSQLAPI FirstDocker ReadySelf Hosted
Alon Sentinel
Open-source, self-hosted uptime and API monitoring built in Rust.
API-first, site-centric, and designed for HTTP and API assertions, SSL, DNS, TCP, heartbeat monitoring, incidents, notifications, public status pages, automation, and future agent-based infrastructure visibility.
Sentinel Admin
Why Sentinel
Monitoring that is built around services, not just checks
Sentinel groups HTTP, SSL, DNS, TCP, and heartbeat monitors around sites, so failures, recoveries, incidents, and public status pages all share one operational context.
Automatic incident lifecycle
Open incidents when checks fail, resolve them on recovery, and keep the timeline intact.
Public status pages
Publish service health without exposing the internal admin surface.
API-first architecture
Drive configuration, checks, incidents, and status data through the versioned HTTP API.
Scoped API clients
Issue bearer tokens with narrow permissions for automation and integrations.
Rust + PostgreSQL foundation
Run a typed, async backend with durable operational history in PostgreSQL.
API monitoring with assertions
Monitor APIs with status code checks, response time thresholds, JSON path assertions, header assertions, body checks, and incident tracking. Alon Sentinel can detect broken API behavior even when the endpoint still returns 200 OK.
Self-hosted uptime monitoring
Run Alon Sentinel with Docker Compose and PostgreSQL to monitor HTTP, SSL, DNS, TCP, and heartbeat checks while retaining ownership of your monitoring data, incidents, notifications, and public status pages.
Benchmarks
Validated with 10,000 HTTP monitors
A healthy-target benchmark completed 453,054 of 453,666 expected checks over a 2,722-second measurement window, with 0.1% missed checks and no worker errors.
The dedicated benchmark report includes the test environment, failure-storm results, raw methodology, and a 4,000-monitor comparison with Uptime Kuma using SQLite and MariaDB.
Read the complete benchmark report10,000
HTTP monitors
99.86%
Checks executed
286.8 MiB
Average full-stack RAM
67.9%
Average full-stack CPU
Screenshots
Built for the admin console operators actually use
Large, direct views for checks, incidents, service state, and public reporting.
Site dashboard
Service health, recent checks, incident state, and uptime windows in one view.
Monitor detail and history
Inspect monitor configuration, check outcomes, response data, and failures.
Multi-site operations
Track multiple services with shared operational context and fast triage.
Public status pages
Expose current service state and incident communication to users.
Features
Coverage for infrastructure, operations, and automation
Monitoring
- HTTP status checks
- JSON path assertions
- Header assertions
- SSL certificate expiry
- DNS record checks
- TCP port checks
- Heartbeat monitoring
Operations
- Incident open/resolve lifecycle
- Operational timelines
- Recovery tracking
- Downtime history
- Public status pages
Security/API
- Admin users
- RBAC roles
- API clients
- Scoped bearer tokens
- OpenAPI specification
- Auth rate limiting
- Audit logs
Deployment
- Docker Compose
- PostgreSQL
- Separate API and worker processes
- Reverse proxy support
- Self-hosted data ownership
Architecture
Separate API and workers, backed by PostgreSQL
Sentinel runs as separate API and worker processes backed by PostgreSQL. The UI is optional - every capability is available through the versioned /v1 HTTP API.
React Admin UI
v
Rust API Server
PostgreSQL
^
Tokio Worker Processes
v
HTTP / SSL / DNS / TCP / Heartbeat Checks
Demo
Public demo
Explore the hosted demo instance at demo.alon.systems.
Demo credentials
Email
demo@alon.systemsPassword
Demo123$Docker Compose
cp .env.example .env
docker compose up -dCommercial Services