Welcoming Repositories Index Crystal Ecosystem
Top Welcoming Open-Source Crystal Repositories
Top welcoming Crystal repositories. Scored by real 90-day external PR merge rates, maintainer review turnaround speed, and first-time contributor success.
Updated daily • Sat, 10 Oct 2026 UTC
Tracked Repos
60
>100 stars verified
Avg Merge Rate
31%
90-day external PRs
Open GFIs
7
Beginner friendly issues
Welcoming Tier
7
S & A Tier maintainers
Ranked Crystal Repositories
Showing top 50 of 60 ranked repositories
| Rank | Repository | Tier | Score | Merge Rate | Good First Issues |
|---|---|---|---|---|---|
| #1 | owasp-noir/noir1,451 Hunt every Endpoint in your code, expose Shadow APIs, map the Attack Surface. | A•Welcoming | 66.4 | 91.5% | 3 |
| #2 | cloudamqp/lavinmq1,027 Ultra quick message queue and streaming server | A•Welcoming | 63.5 | 39.1% | - |
| #3 | A static code analysis tool for Crystal | A•Welcoming | 61.9 | 72.2% | 1 |
| #4 | crystal-lang/crystal20,372 The Crystal Programming Language | A•Welcoming | 61.8 | 57.3% | 1 |
| #5 | kemalcr/kemal3,923 Fast, Effective, Simple Web Framework | A•Welcoming | 60.9 | 76.2% | 1 |
| #6 | The batteries-included web framework for Crystal. | A•Welcoming | 59.5 | 95.8% | - |
| #7 | HTTP/2 Protocol Implementation for the Crystal Language | B•Solid | 58.7 | 100.0% | - |
| #8 | iv-org/invidious22,675 Invidious is an alternative front-end to YouTube | A•Welcoming | 58.4 | 18.5% | 1 |
| #9 | An intelligent AMQP proxy, with connection and channel pooling/reusing | B•Solid | 54.9 | 75.0% | - |
| #10 | HTTP load testing for CI/CD — honest latency, CI thresholds, single binary, JSON output | B•Solid | 54.7 | 100.0% | - |
| #11 | Yet another markdown parser, Compliant to CommonMark specification, written in Crystal. | B•Solid | 54.1 | 80.0% | - |
| #12 | 🏴☠️ Find dead-links (broken links) | B•Solid | 51.7 | 100.0% | - |
| #13 | An ecosystem of reusable, independent components | B•Solid | 47.0 | 75.0% | - |
| #14 | Common db api for crystal | B•Solid | 45.6 | 50.0% | - |
| #15 | Simple, efficient job processing for Crystal | B•Solid | 44.6 | 0.0% | - |
| #16 | The microframework for writing powerful web applications. | B•Solid | 44.6 | 0.0% | - |
| #17 | mint-lang/mint4,268 🍃 A refreshing programming language for the front-end web. | B•Solid | 44.2 | 80.0% | - |
| #18 | Dependency manager for the Crystal language | B•Solid | 43.1 | 12.5% | - |
| #19 | A performant, and portable jq wrapper to facilitate the consumption and output of formats other than JSON; using jq filters to transform the data. | B•Solid | 42.9 | 100.0% | - |
| #20 | HTTP and REST client for Crystal | B•Solid | 42.1 | 100.0% | - |
| #21 | luckyframework/lucky2,735 A full-featured Crystal web framework that catches bugs for you, runs incredibly fast, and helps you write code that lasts. | B•Solid | 41.5 | 100.0% | - |
| #22 | The easiest and fastest way to create production-ready Kubernetes clusters on Hetzner Cloud | C•Moderate | 38.3 | 80.0% | - |
| #23 | ActivityPub (https://www.w3.org/TR/activitypub/) server for individual users and small groups. | C•Moderate | 34.0 | 41.2% | - |
| #24 | amberframework/amber2,608 A Crystal web framework that makes building applications fast, simple, and enjoyable. Get started with quick prototyping, less bugs, and blazing fast performance. | C•Moderate | 25.7 | 0.0% | - |
| #25 | a postgres driver for crystal | D•Risky | 23.8 | 0.0% | - |
| #26 | Automatically skip sponsor segments and ads in YouTube videos playing on Chromecast. | D•Risky | 15.5 | 0.0% | - |
| #27 | A Language Server Protocol implementation for Crystal. 🔮 | D•Risky | 8.0 | 0.0% | - |
| #28 | List of All Programming Telegram Group | D•Risky | 8.0 | 0.0% | - |
| #29 | oprypin/nightly.link1,012 Downloads the latest "nightly" build/artifact from a continuous testing workflow | D•Risky | 8.0 | 0.0% | - |
| #30 | Crystal ORM using ActiveRecord pattern with flexible query DSL | D•Risky | 8.0 | 0.0% | - |
| #31 | :guitar: :notes: A music downloader that understands your metadata needs. | D•Risky | 8.0 | 0.0% | - |
| #32 | Full featured Redis client for Crystal | D•Risky | 8.0 | 0.0% | - |
| #33 | Crystal bindings to SFML multimedia/game library | D•Risky | 8.0 | 0.0% | - |
| #34 | Database wrapper and ORM for Crystal, inspired by Ecto | D•Risky | 8.0 | 0.0% | - |
| #35 | A speculative new protocol 🌸 | D•Risky | 8.0 | 0.0% | - |
| #36 | :book: Examples of GOF patterns written in Crystal | D•Risky | 8.0 | 0.0% | - |
| #37 | 已弃用，请转向 Policr Mini | D•Risky | 8.0 | 0.0% | - |
| #38 | Build/Runs your crystal application, watches files, and rebuilds/restarts app on file changes | D•Risky | 8.0 | 0.0% | - |
| #39 | Advanced ORM between postgreSQL and Crystal | D•Risky | 8.0 | 0.0% | - |
| #40 | Decrypt CIA/3DS roms in UNIX environments (Linux and macOS) | D•Risky | 8.0 | 0.0% | - |
| #41 | f/guardian280 Guardian watches over your files and run assigned tasks. | D•Risky | 8.0 | 0.0% | - |
| #42 | Minimum High Performance Middleware for Crystal Web Server. | D•Risky | 8.0 | 0.0% | - |
| #43 | Slim-inspired templating language for Crystal | D•Risky | 8.0 | 0.0% | - |
| #44 | [MIRROR] 🦈🏳️⚧️🏳️🌈 Gay sharks at your local terminal - lolcat-like CLI tool | D•Risky | 8.0 | 0.0% | - |
| #45 | a graphql implementation for crystal | D•Risky | 8.0 | 0.0% | - |
| #46 | JWT implementation in Crystal | D•Risky | 8.0 | 0.0% | - |
| #47 | tbrand/neph205 A modern command line job processor, similar with make command | D•Risky | 8.0 | 0.0% | - |
| #48 | Thread-safe, persistent, immutable collections for the Crystal language | D•Risky | 8.0 | 0.0% | - |
| #49 | 🐈 The Charly Programming Language | Written by @KCreate | D•Risky | 8.0 | 0.0% | - |
| #50 | [MIRROR] Check hashes for your files - A GUI tool to generate, compare and verify MD5, SHA-1, SHA-256, SHA-512, Blake3, CRC32 & Adler32 hashes. | D•Risky | 8.0 | 0.0% | - |
How to Get Your Crystal PR Merged
1
Check C-Rank™ First: Pick projects with S or A tiers to avoid maintainer ghosts and slow review cycles.
2
Run Local Verification: Ensure test suites and formatting linters pass before opening a pull request.
3
Submit in Maintainer Windows: Check the repository report card to submit when maintainers are most active.
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Frequently Asked Questions: Crystal Open Source
What is the most welcoming Crystal open-source repository?
The highest-ranked Crystal repository on GetMerged is currently owasp-noir/noir, with a C-Rank score of 66.4/100 and a 91.5% PR merge rate.
How can I find good first issues in Crystal?
You can browse verified beginner-friendly issues in Crystal by visiting our curated Good First Issues directory at getmerged.abhishekco.de/good-first-issue/crystal.
What makes a Crystal repository ‘Super Welcoming’ on GetMerged?
A ‘Super Welcoming’ (S-Tier) Crystal repository demonstrates an external PR merge rate above 80%, a median first response time within 24 to 48 hours, active review feedback, and clear onboarding documentation.