github.com/kataras/iris

Iris delivers impressive runtime performance with built-in connection pooling and smart resource management. The context pooling mechanism significantly reduces GC pressure under load, and I've seen consistent sub-millisecond response times in production. The built-in request/response compression and caching middleware work well out of the box.

The framework provides extensive logging hooks and middleware chains that integrate cleanly with structured logging. Error handling is straightforward with customizable error handlers per route or globally. Timeout configuration is granular - you can set deadlines at server, route, and handler levels. The built-in recovery middleware handles panics gracefully without dropping connections.

One significant gotcha: the module path has changed across versions (kataras/iris/v12 is the current production path, not the 0.0.2 version shown). This versioning confusion has caused import headaches during upgrades. Configuration is flexible via functional options, though some defaults (like read timeout) require explicit setting for production workloads. Documentation is comprehensive but scattered across wiki and examples.

Iris offers an impressively comprehensive feature set out of the box, including MVC patterns, sessions, WebSockets, and JWT authentication. The framework feels more like a complete web application platform than a minimal router. However, the Go module versioning situation is problematic - the v12.x.x releases use import path 'github.com/kataras/iris/v12', while the registry shows an outdated 0.0.2 version, creating immediate confusion during onboarding.

The documentation is extensive with many examples, but the learning curve is steeper than alternatives like Echo or Gin due to Iris's unique abstractions and conventions. Error messages are generally helpful when dealing with routing issues, but debugging middleware chains can be opaque. The Context API is powerful but differs significantly from standard library patterns, making it harder to apply general Go web knowledge.

Community support exists but is more limited compared to mainstream alternatives. GitHub issues get responses, though sometimes slowly. Stack Overflow has fewer Iris-specific answers, so you'll often dig through GitHub issues or the framework's own wiki for solutions to non-trivial problems.

Iris delivers impressive runtime performance with minimal memory overhead in production. The built-in connection pooling is solid, and I've had success running it under heavy load with predictable resource consumption. The context-based request handling is clean and the middleware chain performs well without unnecessary allocations.

What stands out is the comprehensive feature set - built-in sessions, WebSocket support, view engines, and structured logging hooks all work out of the box. The configuration system is flexible with environment-specific settings and sensible timeout defaults. Error handling is straightforward with customizable error handlers and proper recovery middleware. Observability is good with hooks for metrics and logging at various pipeline stages.

The main pain point is version instability - the project has gone through breaking changes between major versions, and the v0.0.2 versioning is misleading (actual usage typically involves v12.x tags). Once you pin to a specific version, it's stable, but upgrades require careful testing. Documentation is extensive though sometimes outdated for newer features.