Welcoming Repositories Index Ocaml Ecosystem
Top Welcoming Open-Source Ocaml Repositories
Top welcoming Ocaml repositories. Scored by real 90-day external PR merge rates, maintainer review turnaround speed, and first-time contributor success.
Updated daily • Sun, 11 Oct 2026 UTC
Tracked Repos
454
>100 stars verified
Avg Merge Rate
75%
90-day external PRs
Open GFIs
11
Beginner friendly issues
Welcoming Tier
46
S & A Tier maintainers
Ranked Ocaml Repositories
Showing top 50 of 454 ranked repositories
| Rank | Repository | Tier | Score | Merge Rate | Good First Issues |
|---|---|---|---|---|---|
| #1 | OCaml Language Server Protocol implementation | S•Elite | 72.9 | 87.6% | - |
| #2 | ocaml/dune1,922 A composable build system for OCaml. | S•Elite | 72.1 | 83.7% | - |
| #3 | savonet/liquidsoap1,738 Liquidsoap is a statically typed scripting general-purpose language with dedicated operators and backend for all thing media, streaming, file generation, automation, HTTP backend and more. | S•Elite | 71.6 | 81.0% | - |
| #4 | Visual Studio Code extension for OCaml | S•Elite | 71.3 | 88.2% | - |
| #5 | The Xapi Project's XenAPI Server | S•Elite | 70.3 | 83.2% | - |
| #6 | Proof assistant based on the λΠ-calculus modulo rewriting | A•Welcoming | 68.6 | 79.5% | - |
| #7 | Effects-based direct-style IO for multicore OCaml | A•Welcoming | 68.2 | 84.4% | - |
| #8 | Sail architecture definition language | A•Welcoming | 68.1 | 87.3% | - |
| #9 | Scaling Reasoning for the Age of AI | A•Welcoming | 67.8 | 84.4% | - |
| #10 | ocaml/merlin1,710 Context sensitive completion for OCaml in Vim and Emacs | A•Welcoming | 67.1 | 67.4% | 2 |
| #11 | AeneasVerif/aeneas1,031 A verification toolchain for Rust programs | A•Welcoming | 67.0 | 62.8% | 1 |
| #12 | Build valid HTML and SVG documents | A•Welcoming | 66.5 | 89.7% | - |
| #13 | Static analysis framework for C | A•Welcoming | 66.0 | 64.6% | 3 |
| #14 | EasyCrypt: Computer-Aided Cryptographic Proofs | A•Welcoming | 65.4 | 68.8% | - |
| #15 | ReScript is a robustly typed language that compiles to efficient and human-readable JavaScript. | A•Welcoming | 64.8 | 75.3% | - |
| #16 | Archive for all Rocq and Coq-related opam packages organized in various repositories | A•Welcoming | 64.4 | 78.8% | - |
| #17 | OCaml - Oxidized! | A•Welcoming | 64.3 | 57.8% | - |
| #18 | SIMT Abstractions for Runtime Extensible Kernels (GPGPU programing with OCaml) | A•Welcoming | 64.3 | 94.2% | - |
| #19 | The Herd toolsuite to deal with .cat memory models (version 7.xx) | A•Welcoming | 63.9 | 65.7% | - |
| #20 | Simple high-level language for writing Internet Computer canisters | A•Welcoming | 63.7 | 68.9% | - |
| #21 | Virt-v2v converts guests from foreign hypervisors to run on KVM | A•Welcoming | 63.4 | 86.7% | - |
| #22 | Jacquard is a small programming language designed for a regime in which most code is written by machine-learning models and reviewed by people. | A•Welcoming | 62.4 | 89.9% | - |
| #23 | ocsigen/js_of_ocaml1,135 Compiler from OCaml to Javascript. | A•Welcoming | 62.2 | 82.4% | - |
| #24 | Terraform without the state file bottleneck | A•Welcoming | 61.8 | 66.7% | - |
| #25 | MinaProtocol/mina2,124 Mina is a cryptocurrency protocol with a constant size blockchain, improving scaling while maintaining decentralization and security. | A•Welcoming | 61.7 | 55.7% | - |
| #26 | Rocq plugin embedding Elpi | A•Welcoming | 61.6 | 67.9% | - |
| #27 | opengrep/opengrep3,165 🔎 Static code analysis engine to find security issues in code. | A•Welcoming | 61.2 | 81.8% | - |
| #28 | ocaml/opam1,382 opam is a source-based package manager. It supports multiple simultaneous compiler installations, flexible package constraints, and a Git-friendly development workflow. | A•Welcoming | 60.8 | 68.8% | - |
| #29 | GeneWeb is a free (as in free speech) genealogy software with a web interface created by Daniel de Rauglaudre. | A•Welcoming | 60.7 | 81.6% | - |
| #30 | Visual Studio Code extension for Rocq | A•Welcoming | 60.4 | 68.8% | - |
| #31 | OCamlPro/owi323 Owi: Seamless program analysis for C, C++, Go, Haskell, LLVM, Rust, Wasm and Zig. | A•Welcoming | 60.3 | 80.0% | - |
| #32 | The Stan transpiler (from Stan to C++ and beyond). | A•Welcoming | 60.3 | 74.1% | 2 |
| #33 | An engine for displaying slips, the next-gen version of slides | A•Welcoming | 60.1 | 88.6% | - |
| #34 | Multi-engine SMT-based automatic model checker for safety properties of Lustre programs | A•Welcoming | 60.0 | 77.3% | - |
| #35 | rocq-prover/rocq5,599 The Rocq Prover is an interactive theorem prover, or proof assistant. It provides a formal language to write mathematical definitions, executable algorithms and theorems together with an environment for semi-interactive development of machine-checked proofs. | A•Welcoming | 59.7 | 60.2% | - |
| #36 | Pure OCaml implementation of Zlib. | A•Welcoming | 59.2 | 90.0% | - |
| #37 | Terrateam is open-source GitOps infrastructure orchestration. It integrates with GitHub to automate Terraform, OpenTofu, CDKTF, Terragrunt, and Pulumi workflows through pull requests. | A•Welcoming | 58.9 | 66.9% | - |
| #38 | Albatross: orchestrate and manage MirageOS unikernels with Solo5 | B•Solid | 58.2 | 100.0% | - |
| #39 | ocaml/ocaml6,601 The core OCaml system: compilers, runtime system, base libraries | A•Welcoming | 58.0 | 56.4% | 1 |
| #40 | CatalaLang/catala2,418 Programming language for literate programming law specification | A•Welcoming | 57.8 | 73.5% | - |
| #41 | ocaml/odoc356 Documentation compiler for OCaml | A•Welcoming | 57.3 | 63.8% | 2 |
| #42 | Execute code blocks inside your documentation | B•Solid | 57.3 | 83.3% | - |
| #43 | Purely functional SSH library in ocaml. | A•Welcoming | 57.2 | 50.0% | - |
| #44 | An experimental programming language | B•Solid | 57.1 | 100.0% | - |
| #45 | facebook/infer15,716 A static analyzer for Java, C, C++, and Objective-C | A•Welcoming | 56.9 | 42.3% | - |
| #46 | The TLA⁺ Proof Manager | A•Welcoming | 56.9 | 53.3% | - |
| #47 | An OCaml lexer generator for Unicode | A•Welcoming | 56.3 | 41.7% | - |
| #48 | A simple scheduler for OCaml 5 | A•Welcoming | 55.9 | 85.7% | - |
| #49 | OCaml implementation of the DNS protocol | B•Solid | 55.9 | 75.0% | - |
| #50 | An OCaml library for HTTP clients and servers using Lwt or Async | A•Welcoming | 55.8 | 70.0% | - |
How to Get Your Ocaml 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: Ocaml Open Source
What is the most welcoming Ocaml open-source repository?
The highest-ranked Ocaml repository on GetMerged is currently ocaml/ocaml-lsp, with a C-Rank score of 72.9/100 and a 87.6% PR merge rate.
How can I find good first issues in Ocaml?
You can browse verified beginner-friendly issues in Ocaml by visiting our curated Good First Issues directory at getmerged.abhishekco.de/good-first-issue/ocaml.
What makes a Ocaml repository ‘Super Welcoming’ on GetMerged?
A ‘Super Welcoming’ (S-Tier) Ocaml 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.