Add Rails: Ruby on Rails in API mode on Puma (~58k ⭐)

[BennyFranciscus]

Rails — Ruby on Rails (API mode)

Language: Ruby
Framework: Rails (~58k ⭐)
Server: Puma (multi-worker, 4 threads per worker)

Why Rails?

HttpArena already has Sinatra (Ruby micro framework) — Rails completes the Ruby comparison. This is the most iconic web framework ever built. Convention over configuration, the framework that launched a thousand startups. Django vs Flask is already represented for Python — now we have the Ruby equivalent: Rails vs Sinatra.

Implementation

• Rails 8.0 in API mode (no views, no assets, no ActionCable — pure JSON/text API)
• Stripped middleware: removed HostAuthorization, RemoteIp, RequestId, Logger, ShowExceptions, Callbacks
• Pre-computed JSON + gzip payloads at boot (same pattern as other entries)
• Thread-local SQLite connections with mmap
• Puma with 1 worker per CPU core, 4 threads each
• Logging disabled (writes to /dev/null)

The interesting comparison

• Sinatra vs Rails: micro DSL vs full-stack framework, same language, same server (Puma). How much overhead does Rails' routing, middleware stack, and controller abstraction add?
• Django vs Rails: the two frameworks that defined modern web development. Same philosophy (batteries-included, convention over configuration), different languages.
• Flask vs Sinatra: the micro framework comparison (already possible, now with Rails/Django as the full-stack counterpart)

Endpoints

All 8 standard endpoints implemented: /pipeline, /baseline11, /baseline2, /json, /compression, /db, /upload

cc @tenderlove @rafaelfranca @matthewd — would love to see how Rails stacks up in HttpArena! 🚂

[BennyFranciscus]

CI is hitting the port 8080 conflict on the self-hosted runner (stale Docker container from a previous run). Same issue as #75 and #77. Docker build succeeds — it's the docker run -p 8080:8080 that fails because the port is already allocated.

Happy to re-trigger once the runner is cleaned up! 🙂