Welcoming Repositories Index Erlang Ecosystem
Top Welcoming Open-Source Erlang Repositories
Top welcoming Erlang 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
196
>100 stars verified
Avg Merge Rate
73%
90-day external PRs
Open GFIs
9
Beginner friendly issues
Welcoming Tier
11
S & A Tier maintainers
Ranked Erlang Repositories
Showing top 50 of 196 ranked repositories
| Rank | Repository | Tier | Score | Merge Rate | Good First Issues |
|---|---|---|---|---|---|
| #1 | emqx/emqx16,778 The most scalable and reliable MQTT broker for AI, IoT, IIoT and connected vehicles | S•Elite | 71.9 | 68.4% | - |
| #2 | processone/ejabberd6,717 Robust, Ubiquitous and Massively Scalable Messaging Platform (XMPP, MQTT, SIP Server) | A•Welcoming | 65.5 | 93.3% | - |
| #3 | esl/MongooseIM1,760 MongooseIM is Erlang Solutions' robust, scalable and efficient XMPP server, aimed at large installations. Specifically designed for enterprise purposes, it is fault-tolerant and can utilise the resources of multiple clustered machines. | A•Welcoming | 65.0 | 72.7% | - |
| #4 | erlang/otp12,323 Erlang/OTP | A•Welcoming | 64.8 | 48.3% | 7 |
| #5 | DNS server, in Erlang. | A•Welcoming | 63.6 | 100.0% | - |
| #6 | erlang/rebar31,821 Erlang build tool that makes it easy to compile and test Erlang applications and releases. | A•Welcoming | 63.2 | 95.0% | - |
| #7 | emqx/esockd214 Erlang general non-blocking TCP/SSL socket server | B•Solid | 62.0 | 85.7% | - |
| #8 | Khepri is a tree-like replicated on-disk database library for Erlang and Elixir. | A•Welcoming | 61.9 | 93.8% | - |
| #9 | apache/couchdb6,939 Seamless multi-primary syncing database with an intuitive HTTP/JSON API, designed for reliability | A•Welcoming | 61.7 | 50.0% | 2 |
| #10 | Apache Kafka client library for Erlang/Elixir | B•Solid | 58.0 | 100.0% | - |
| #11 | grisp/grisp324 🐟 GRiSP Erlang Runtime Library | B•Solid | 58.0 | 100.0% | - |
| #12 | aeternity/aeternity1,087 æternity blockchain - scalable blockchain for the people - smart contracts, state channels, names, tokens | A•Welcoming | 56.9 | 81.8% | - |
| #13 | Zotonic - The Erlang Web Framework & CMS | A•Welcoming | 56.8 | 63.9% | - |
| #14 | Chef Infra Server is a hub for configuration data; storing cookbooks, node policies and metadata of managed nodes. | A•Welcoming | 56.8 | 75.0% | - |
| #15 | Erlang worker pool | B•Solid | 54.5 | 100.0% | - |
| #16 | STUN / TURN standalone server | B•Solid | 54.3 | 87.5% | - |
| #17 | rabbitmq/ra976 A Multi-Raft implementation for Erlang and Elixir that strives to be efficient and make it easier to use multiple Raft clusters in a single system. | B•Solid | 54.1 | 100.0% | - |
| #18 | OpenTelemetry Erlang SDK | B•Solid | 52.4 | 60.0% | - |
| #19 | Web framework for the BEAM — Erlang, Elixir, and LFE | B•Solid | 51.4 | 100.0% | - |
| #20 | kivra/oauth2221 Erlang Oauth2 implementation | B•Solid | 50.7 | 100.0% | - |
| #21 | MongoDB driver for Erlang | B•Solid | 50.2 | 100.0% | - |
| #22 | A pure Erlang Key/Value store - based on a LSM-tree, optimised for HEAD requests | B•Solid | 50.0 | 66.7% | - |
| #23 | emqx/emqtt440 Erlang MQTT 5.0 Client | B•Solid | 48.9 | 75.0% | - |
| #24 | Concuerror is a stateless model checking tool for Erlang programs. | B•Solid | 48.6 | 100.0% | - |
| #25 | Apple Push Notification Server for Erlang | B•Solid | 48.3 | 100.0% | - |
| #26 | inaka/elvis435 Erlang Style Reviewer | B•Solid | 48.2 | 100.0% | - |
| #27 | Dynamic dispatching library for metrics and instrumentations. | B•Solid | 47.2 | 100.0% | - |
| #28 | happi/theBeamBook4,057 A description of the Erlang Runtime System ERTS and the virtual Machine BEAM. | B•Solid | 46.9 | 100.0% | - |
| #29 | XML parser for Erlang | B•Solid | 46.9 | 100.0% | - |
| #30 | Lightweight MQTT benchmark tool written in Erlang | B•Solid | 46.8 | 100.0% | - |
| #31 | A blockchain for trust-free markets in financial derivatives | B•Solid | 46.4 | 0.0% | - |
| #32 | ferd/recon1,431 Collection of functions and scripts to debug Erlang in production. | B•Solid | 46.3 | 100.0% | - |
| #33 | yakaz/yamerl213 YAML 1.2 and JSON parser in pure Erlang | B•Solid | 46.0 | 100.0% | - |
| #34 | High-Performance Erlang Network Client Framework | B•Solid | 45.8 | 80.0% | - |
| #35 | rvirding/luerl1,193 Lua in Erlang | B•Solid | 45.7 | 100.0% | - |
| #36 | Erlware Commons is an Erlware project focused on all aspects of reusable Erlang components. | B•Solid | 45.5 | 100.0% | - |
| #37 | Growing and curated ejabberd contributions repository - PR or ask to join ! | B•Solid | 45.5 | 100.0% | - |
| #38 | benoitc/hackney1,420 simple HTTP client in Erlang | B•Solid | 44.6 | 33.3% | - |
| #39 | Prometheus.io client in Erlang | B•Solid | 43.9 | 75.0% | - |
| #40 | synrc/n2o1,340 ⭕ N2O: Distributed WebSocket Application Server ISO 20922 | B•Solid | 43.5 | 100.0% | - |
| #41 | A visual tracer and profiler for Erlang and Elixir. | B•Solid | 43.5 | 0.0% | - |
| #42 | uwiger/gproc1,101 Extended process registry for Erlang | B•Solid | 43.2 | 100.0% | - |
| #43 | uwiger/locks210 A scalable, deadlock-resolving resource locker | C•Moderate | 39.9 | 0.0% | - |
| #44 | Erlang PostgreSQL client library. | B•Solid | 38.9 | 0.0% | - |
| #45 | mochi/mochiweb1,889 MochiWeb is an Erlang library for building lightweight HTTP servers. | C•Moderate | 35.4 | 0.0% | - |
| #46 | erlang tracing debugger | C•Moderate | 35.3 | 66.7% | - |
| #47 | A REST-based system for building web applications. | C•Moderate | 33.3 | 100.0% | - |
| #48 | dgud/wings669 Wings3D is an advanced sub-division 3D modeller. | C•Moderate | 33.3 | 0.0% | - |
| #49 | lfe/lfe2,460 Lisp Flavoured Erlang (LFE) | C•Moderate | 32.7 | 0.0% | - |
| #50 | Compact server for private LoRaWAN networks | D•Risky | 29.9 | 0.0% | - |
How to Get Your Erlang 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: Erlang Open Source
What is the most welcoming Erlang open-source repository?
The highest-ranked Erlang repository on GetMerged is currently emqx/emqx, with a C-Rank score of 71.9/100 and a 68.4% PR merge rate.
How can I find good first issues in Erlang?
You can browse verified beginner-friendly issues in Erlang by visiting our curated Good First Issues directory at getmerged.abhishekco.de/good-first-issue/erlang.
What makes a Erlang repository ‘Super Welcoming’ on GetMerged?
A ‘Super Welcoming’ (S-Tier) Erlang 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.