Libraries and tools for package and dependency management.

• hex.pm - A package manager for the Erlang ecosystem.

Libraries and tools for release management.

• relx - A release assembler for Erlang.

Libraries and tools related to configuration management.

• stillir - Cache environment variables as Erlang app variables.

Libraries and tools to maintain a clean codebase.

• elvis - Erlang Style Reviewer.

Web development frameworks.

• Axiom - A micro-framework, inspired by Ruby's Sinatra.
• ChicagoBoss - A server framework inspired by Rails and written in Erlang.
• cowboy - A simple HTTP server.
• Giallo - A small and flexible web framework on top of Cowboy.
• MochiWeb - An Erlang library for building lightweight HTTP servers.
• N2O - WebSocket Application Server.
• Nitrogen - Framework to build web applications (including front-end) in pure Erlang.
• Zotonic - High speed, real-time web framework and content management system.

Standalone component from web development frameworks.

• cb_admin - An admin interface for Chicago Boss.
• cb_websocket_controller - A template for implementing a Websocket controller for ChicagoBoss.
• giallo_session - A session management library for the Giallo web framework.
• simple_bridge - An abstraction layer providing a unified interface to popular Erlang web servers (Cowboy, Inets, Mochiweb, Webmachine, and Yaws).

Libraries for working with HTTP and scraping websites.

• bullet - Simple, reliable, efficient streaming for Cowboy.
• gun - Erlang HTTP client with support for HTTP/1.1, SPDY and Websocket.
• hackney - Simple HTTP client in Erlang.
• ibrowse - Erlang HTTP client.
• lhttpc - A lightweight HTTP/1.1 client implemented in Erlang.
• shotgun - For the times you need more than just a gun.

Libraries for testing codebases and generating test data.

• PropEr - A QuickCheck-inspired property-based testing tool for Erlang.
• tracerl - Dynamic tracing tests and utilities for Erlang/OTP

Libraries for generating and working with log files.

• lager - A logging framework for Erlang/OTP.
• lager_amqp_backend - AMQP RabbitMQ Lager backend.
• lager_hipchat - HipChat backend for lager.
• lager_loggly - Loggly backend for lager.
• lager_smtp - SMTP backend for lager.
• lager_slack - Simple Slack backend for lager.
• logplex - Heroku log router.

Libraries for gathering metrics and monitoring.

• entop - A top-like Erlang node monitoring tool.
• eper - A loose collection of Erlang Performance related tools.
• Exometer - An Erlang instrumentation package.
• folsom - An Erlang based metrics system inspired by Coda Hale's metrics.
• statsderl - A statsd Erlang client.
• vmstats - Tiny Erlang app that works in conjunction with statsderl in order to generate information on the Erlang VM for graphite logs.

Libraries and tools related to deployment of Erlang/OTP applications.

• docker-erlang - Basic Docker Container Images for Erlang/OTP.

Tools for stress/load testing, latency issues, etc. across microservices.

• Typhoon - Stress and load testing tool for distributed systems that simulates traffic from a test cluster toward a system-under-test (SUT) and visualizes related latencies.

Libraries and tools for analysing, parsing and manipulation codebases.

• Concuerror - Concuerror is a systematic testing tool for concurrent Erlang programs.
• eflame - A Flame Graph profiler for Erlang.
• geas - Geas is a tool that will detect the runnable official Erlang release window for your project, including its dependencies and provides many useful informations.

Project build and automation tools.

• rebar - Erlang build tool that makes it easy to compile and test Erlang applications, port drivers and releases.
• rebar3 - A build tool for Erlang which can manage Erlang packages from Hex.pm. See more at rebar3.org
• sync - On-the-fly recompiling for Erlang.

Libraries for geocoding addresses and working with latitudes and longitudes.

• erl-rstar - An Erlang implementation of the R*-tree spacial data structure.
• GeoCouch - A spatial extension for Couchbase and Apache CouchDB.
• Teles - An Erlang network service for manipulating geographic data.

Libraries and tools for debugging code and applications.

• tx - An HTML Erlang term viewer, starts own webserver and displays any term you give it from your Erlang node.

Libraries and tools for working with actors and such.

• poolboy - A hunky Erlang worker pool factory.

Libraries for working with dates and times.

• erlang_localtime - Erlang library for conversion from one local time to another.
• qdate - Erlang date, time, and timezone management: formatting, conversion, and date arithmetic.

Libraries that implement object-relational mapping or datamapping techniques.

• boss_db - A sharded, caching, pooling, evented ORM for Erlang.
• epgsql - PostgreSQL Driver for Erlang.
• mysql-otp - MySQL/OTP – MySQL driver for Erlang/OTP.
• pgsql_migration – PostgreSQL migrations for Erlang.

Libraries for working with event and task queues.

• dq - Distributed Fault Tolerant Queue library.
• ebqueue - Tiny simple blocking queue in erlang.
• pqueue - Erlang Priority Queues.
• tinymq - A diminutive, in-memory message queue for Erlang.

Libraries for implementing authentications schemes.

• oauth2 - Erlang Oauth2 implementation.

Libraries for parsing and manipulating text and numbers.

• ejsv - Erlang JSON schema validator.
• eql - Erlang with SQL or not.
• jiffy - JSON NIFs for Erlang.
• jsx - An erlang application for consuming, producing and manipulating json.
• miffy - Jiffy wrapper which returns pretty maps.
• qsp - Enhanced query string parser for Erlang.
• rec2json - Generate JSON encoder/decoder from record specs.

Libraries and web tools for developing REST-ful APIs.

• leptus - Leptus is an Erlang REST framework that runs on top of cowboy.
• rooster - rooster is a lightweight REST framework that runs on top of mochiweb.

Libraries for caching data.

• cache - In-memory Segmented Cache

Libraries for accessing third party APIs.

• google-token-erlang - Google ID token verifier for Erlang.
• restc - An Erlang REST client
• oauth2c - An Erlang oAuth 2 client (uses restc)

Libraries and tools for using network related stuff.

• barrel_tcp - barrel_tcp is a generic TCP acceptor pool with low latency in Erlang.
• gen_rpc - A scalable RPC library for Erlang-VM based languages.
• gen_tcp_server - A library that takes the concept of gen_server and introduces the same mechanics for operating a TCP server.
• gossiperl - Language agnostic gossip middleware and message bus written in Erlang.
• nat_upnp - Erlang library to map your internal port to an external using UNP IGD.
• ranch - Socket acceptor pool for TCP protocols.

Libraries and tools for interacting with the physical world.

• GRiSP - Run the Erlang VM on an IoT board with many hardware interfaces and low-level drivers using a small realtime unikernel called RTEMS
• lemma_erlang - A lemma for IDEO's Noam internet-of-things prototyping platform.

Libraries and implementations of algorithms and datastructures.

• datum - A pure functional and generic programming for Erlang
• erlando - A set of syntax extensions like currying and monads for Erlang.
• statebox - Erlang state "monad" with merge/conflict-resolution capabilities.
• riak_dt - Erlang library of state based CRDTs.

Libraries providing translations or internationalizations.

Useful libraries or tools that don't fit in the categories above.

• erlang-history - Hacks to add shell history to Erlang's shell.
• erld - erld is a small program designed to solve the problem of running Erlang programs as a UNIX daemon.

Resources

Various resources, such as books, websites and articles, for improving your Erlang development skills and knowledge.

Useful web and Erlang-related websites and newsletters.

• Erlang Bookmarks - All about erlang programming language [powerd by community].
• Erlang Central - An awesome collections of erlang resource along with live community chat for discussing and seeking help.
• Planet Erlang - Planet site/RSS feed of blog posts covering topics across the Erlang ecosystem.
• Spawned Shelter - Erlang Spawned Shelter. A collection of the best articles, videos and presentations related to Erlang.

Fantastic books and e-books.

• Erlang and Elixir for Imperative Programmers - Introduction to Erlang and Elixir in the context of functional concepts by Wolfgang Loder (2016)
• Learn You Some Erlang - Learn you some Erlang - for great good! A very thorough resource covering everything from beginning Erlang programming to large-scale development and deployment.
• Stuff Goes Bad - ERLANG IN ANGER - This book intends to be a little guide about how to be the Erlang medic in a time of war.

General web-development-related reading materials.

Erlang-releated reading materials.

• The Joy of Erlang; Or, How To Ride A Toruk - The Joy of Erlang; Or, How To Ride A Toruk A fast track introduction to Erlang that teaches the language by walking through a few example projects.

Cool video tutorials.

Contributing

Please see CONTRIBUTING for details.