About Arqen

Arqen is a Rust toolkit for building backend services with HTTP routes, explicit application modules, typed tools, durable jobs, health checks, and Thingd-backed data access.

It is useful for ordinary web and mobile backends, internal services, automation systems, and products that expose selected operations to agents. You can use the backend features without using an AI model or an agent framework.

What you build with Arqen

An Arqen application usually contains:

• HTTP routes and application state;
• modules that group related routes, tools, jobs, and health checks;
• authentication, authorization, and request validation;
• Thingd objects, events, search, links, and queues;
• workers for work that should continue after a request ends;
• health, readiness, structured logs, and operational metrics.

The application owns its domain models and business rules. Arqen supplies the composition, runtime, and integration points around them.

Implementation boundary

Arqen is Rust-first, but applications should depend on Arqen’s contracts rather than its internal runtime, transport, or storage-engine choices. The HTTP integration is feature-gated. Applications select public storage modes and adapter contracts; the implementation behind those choices can evolve without changing normal application code.

Start with Build an Arqen backend to create a project, add a module, choose storage, define a schema, and prepare a deployment.

Agent support

Agent tools are one way to expose application capabilities. Arqen can describe tool names, inputs, outputs, scopes, effects, and idempotency in a manifest so people and software can discover the same operations. Read the Agent guide when your backend needs that workflow.