Via

Via is a tiny HTTP reverse proxy for when you only need proxy_pass.

Via is a concurrent HTTP reverse proxy written in Crystal. Its current development milestone provides:

• HTTP/1.1 reverse proxying;
• host and path routing;
• streaming request and response bodies;
• downstream and upstream keep-alive;
• reusable upstream connections;
• atomic hot reload for file and directory configurations;
• manual TLS termination with certificate reload;
• static files with cache validators, ranges, and SPA fallback;
• debug diagnostics for invalid configuration;
• strict YAML configuration and validation;
• built-in gateway error pages with request IDs.

Via deliberately stays focused. It does not currently provide caching, FastCGI, WAF functionality, scripting, plugins, complex rewrite rules, or advanced load-balancing algorithms.

Current status

Via is under active development and is not yet a stable production release. WebSocket proxying, configurable headers, and upstream timeouts remain on the roadmap.

Start with Getting started, then see Configuration and routing for route matching behavior and Proxy behavior for forwarding semantics. See Error pages and request IDs for failure behavior and Debug mode and hot reload for the configuration workflow.