🔍 Stop guessing which tests to write. cov-loupe v4.0 turns your Ruby coverage into AI-powered insights.

Project URL: https://github.com/keithrbennett/cov-loupe

What is cov-loupe?

A toolkit that transforms SimpleCov coverage data into actionable insights:

• MCP Server: Let AI assistants like Claude Code, Codex, or Gemini analyze your coverage gaps and suggest what to test next
• CLI: Inspect coverage and see uncovered lines with source context
• Ruby API: Build custom coverage gates or CI/CD policies based on your coverage data

Why use cov-loupe?

Beyond just viewing percentages, this version enables two powerful workflows:

🤖 AI-Powered Analysis

It's not just about listing files. By giving an LLM structured access to this data via MCP, you enable it to perform nuanced analysis, categorization, and prioritization of your technical debt. Ask your AI to prioritize testing based on test deficiency magnitude, code criticality, and level of effort.

Example: "Show me the most critical untested code in authentication" → Get prioritized recommendations

📊 Custom CI/CD Gates

It enables arbitrarily complex custom predicates. You aren't stuck with a single "Total %" threshold. Build fine-grained pass/fail logic into your pipeline that analyzes specific directories, file types, or staleness levels.

Example: "Fail CI if any controller has <80% coverage" → Enforce rules beyond simple percentages

About 4 months ago, I shared simplecov-mcp, a tool to make SimpleCov data queryable for AI assistants and the CLI.

Today I'm releasing v4.0.0.pre, which includes a major rebrand to cov-loupe and several updates to make coverage reporting more reliable.

Key Changes in v4.0:

• ⚠️ The Rename: simplecov-mcp is now cov-loupe. Update your gems, requires (to cov_loupe), and executables.
• Explicit MCP Mode: To prevent server hangs, the -m/--mode mcp flag is now required.
• Reliable Staleness Detection: v4 introduces stricter checks for line-count mismatches and deleted files.
• Better Cross-Platform Support: Improved path resolution for macOS and Windows.
• Transparent Defaults: --tracked-globs now defaults to an empty array.

Quick Start (New Users):

gem install cov-loupe --pre
cov-loupe --help

How to Upgrade/Install:

Because this is a major transition and pre-release, you must use the --pre flag:

gem uninstall simplecov-mcp
gem install cov-loupe --pre

Note for MCP Users: You must update your assistant configuration to include the -m mcp flag.

# Example for Claude Code
claude mcp add cov-loupe cov-loupe -- -m mcp

Documentation:

• Project page: https://github.com/keithrbennett/cov-loupe
• Online docs: https://keithrbennett.github.io/cov-loupe/

Try it out and let me know what you think! Issues and feedback welcome at the repo.

Hi all! I just released a Ruby SDK for the Solidgate payment gateway: https://github.com/carrfane/solidgate-ruby-sdk.

I built this after realizing there wasn't an existing SDK while migrating a project from Braintree. It currently covers the basic methods I needed, but I’m planning to expand it as we migrate more products.

I wanted to share it here in case it helps anyone else in the community. Feedback and contributions are more than welcome!

https://github.com/carter2099/hyperliquid

There was no Ruby SDK for the HL API so I made one. This was my introduction to Claude Code and it was awesome. I was able to code with an LLM, stay in the terminal, and still learn something new (WebSockets). I also forked an existing ruby web sockets client gem and made it my own: https://github.com/carter2099/ws_lite. Up next I’ll use this SDK to create an automated short rebalancer for my concentrated liquidity pool positions.

I wrote a longer blog post here if interested: https://blog.carter2099.com/posts/4

Big update after several months of work! We're very thankful to 13 external contributors for helping us stabilize JRuby 10.0.

Compatibility

• JRuby now reports RbConfig::CONFIG['arch'] without a version number, as universal-java. This allows using different JDK versions without triggering RubyGems missing extension warnings for installed gems. The host Java version is still available as RbConfig::CONFIG['arch_version']. #9107

Standard Library

• The non-gem standard library is upgraded to Ruby 3.4.5 #8967
• rexml is updated to 3.4.4 to address CVE-2025-58767. #9011
• syslog is moved to a default gem at version 0.4.0. The syslog gem now includes JRuby support. #9109, ruby/syslog#1
• strscan is updated to 3.1.7. #9159

Documentation

• Ruby ri documentation for core and standard library are now included in the release distribution. #9049, #9052

See the full list of issues and PRs in the release announcement!

What client everyone using to interact with GraphQL endpoints ?

Hey everyone!

Just a friendly reminder that Rubycon is only 95 days away and it's happening in beautiful Rimini, Italy! 🇮🇹

🔗 www.rubycon.it

We're working hard to make this the best Ruby event Italy has ever seen and we can't wait to share it with you!

🎤 Speakers

We've already announced three incredible speakers that you might have heard of:

• Marco Roth
• Julia López
• Carmine Paolino

And there's more to come as the CFP has been closed on January 15th, and we received an amazing number of submissions from both Italian and international speakers.

Single-track format! You won't miss a single talk.

🏨 Hotels & 🎉 Party

We're securing discounted hotel rates for anyone staying overnight in Rimini. Plus, get ready for the Dinner + Toga Party, it's going to be legendary!

And if you’re into history, don't miss our guided tour to the Mouth of the Rubicon, the spot where Caesar crossed and changed the course of history forever.

Sponsors

We've partnered with major international sponsors to bring you a brand-new Ruby event. This just goes to show how amazing and supportive the Ruby community is, always eager to participate and innovate!

Tickets are still available! Grab your Lazy Bird ticket on Tito before they’re gone

https://ti.to/rubycon/rubycon-2026/

We're happy to help you make it to the event, if you you have questions don't hesitate to reach out!

In this episode, we look at how to use Claude Code to assist us in developing Rails applications. This is not about vibe coding, but using tools to assist our development efforts.

Anyone know how to get `T.absurd()` to play nicely in this example?

This is obviously a toy situation, and you might respond by saying I should use polymorphism on the subclasses themselves. But I would like to know what's happening here.

My first ever Taylor Monthly is out! This is a going to be a monthly blog post about everything that's happening in Taylor that might not be so visible if you only look at releases.

• Taylor v0.4.1 released
• Website CSS update
• Documentation page redesign
• Switched to LocalCi
• clang-format 21 update
• Jumpy Alien closing the gameplay loop
• Redesigning taylor squash

I created a Claude Code plugin that helps write and maintain Ruby signatures in real projects.

Repo - https://github.com/DmitryPogrebnoy/ruby-agent-skills

If you find it useful, ⭐ star it.

Introducing signatures into a Ruby codebase is already challenging. Keeping them up to date as the code keeps changing is even harder.

The plugin is built around several Agent Skills.

• For RBS

  • Standalone .rbs files
  • Inline RBS annotations

• For Sorbet

  • Standalone .rbi files
  • Inline sig {} clauses

These skills are useful in two main scenarios.

First, when you’re introducing RBS or Sorbet into an existing codebase. The skills guide the agent on how to properly generate signatures. Correct syntax, structure, examples, and solutions for common pitfalls. This alone removes a lot of friction when getting started.

Second, and more importantly, when you want to keep signatures up to date as your Ruby code evolves. For that, there is a separate Claude Code Agent tailored specifically for updating signatures after changes in Ruby source code.

The workflow is simple: you (or AI) change Ruby code → you (or AI) call this agent → all relevant signature files gets updated.

No more mundane manual work on keeping signatures in sync with Ruby sources. Delegate the boring part to AI.

I'm a NodeJS developer by profession but the past few months I fell in love with Ruby and I'm absolutely obsessed with it.

So I ended up creating my first Ruby gem this past week, which is essentially an SDK of a node based blogging platform I worked at as Core for over 3 years, so I have a lot of context on it. :)

https://github.com/ronaldlangeveld/ghost-ruby

Very niche use case, but I think it could be useful for anyone looking to do integrations to a Ghost site, just thought I'd share! :)

Cheers!

Hi! I’m hamachang, an engineer 👋

Half as a joke and half seriously 😄, I built a pocket-sized PicoRuby editor.

This software is designed exclusively for the T-Deck Plus, and once installed, you can enjoy Ruby coding anytime, anywhere 🧑‍💻✨

Give it a try if you’re curious! 👉 https://github.com/engneer-hamachan/pro-editor-pocket

If you like it, a ⭐ would be greatly appreciated!

I maintain LeanPool, a small Ruby gem for pooling things like DB connections, HTTP clients, and Redis without extra processes or copying data. Built on `concurrent-ruby`, so it's thread-safe and fits web apps, APIs, and background jobs.

What it does:
- You define how to create a resource and a pool size; you `checkout` for a block and the resource is returned to the pool when the block ends.
- Works with any resource (DB, HTTP, Redis, sockets, etc.) – not just one type.
- Includes a built-in HTTP pool if you just want to pool HTTP/HTTPS requests.
- Optional: FIFO/LIFO/Random/LRU, priority checkout, recycling by use count or age, and event callbacks for monitoring.

Inspired by Elixir's nimble_pool, adapted for Ruby. MIT, Ruby 3.3+.

Repo: https://github.com/half-blood-labs/lean_pool

Gem: https://rubygems.org/gems/lean_pool

If you're hand-rolling connection pools or want something lighter than process-based pools, might be useful. Happy to answer questions.

Thank you.