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Apr 09, 2024

Markdown/Text Processors

• cr-cmark-gfm (⭐20) - Crystal C bindings for cmark-gfm to work with Commonmark and Github Flavored Markdown

Mar 15, 2024

Queues and Messaging

• crafka (⭐15) - Apache Kafka library utilizing librdkafka

Feb 23, 2024

Web Frameworks

• Crystal newsletter

• IRC - #crystal-lang on Libera

Dec 27, 2023

Algorithms and Data structures

• HKDF (⭐1) - HMAC-based Extract-and-Expand Key Derivation Function rfc5869

• named_information (⭐0) - Naming Things with Hashes rfc6920

• SPAKE2+ (⭐1) - Password Authenticated Key Exchange (PAKE) protocol, comparable to SRP-6a

• verhoeff (⭐0) - Implementation of the Verhoeff checksum algorithm

Oct 17, 2023

C bindings

• v4l2.cr (⭐5) - Bindings for Video4Linux2

Sep 13, 2023

Game Development

• Raylib-cr (⭐68) - Direct bindings to Raylib, which supports Linux, Windows, and Mac

Aug 28, 2023

HTML Builders

• to_html (⭐7) - The fastest HTML builder engine for Crystal

Aug 27, 2023

C bindings

• win32cr (⭐11) - Bindings for Win32 API

May 27, 2023

Unofficial

• Crystal Shards for Ruby Gems (⭐19k) - A list of Ruby Gems and their Crystal Shards equivalents

Apr 18, 2023

HTML Builders

• blueprint (⭐37) - Write reusable and testable HTML templates in plain Crystal

Apr 13, 2023

C bindings

• crystal-gsl (⭐2) - Bindings for GNU Scientific Library

Implementations/Compilers

• novika (⭐15) - A free-form, moldable, interpreted programming language

Mar 28, 2023

CLI Utils

• git-repository (⭐2) - A git cli wrapper querying and cloning remote repositories with minimal data transfer

Mar 24, 2023

Editor Plugins

• IntelliJ IDEA
  • intellij-crystal-lang (⭐33) - Crystal support for the JetBrains IDEs

Mar 17, 2023

CLI Builders

• Cling (⭐21) - A modular, non-macro-based command line interface library

Mar 16, 2023

Database Drivers/Clients

• surrealdb.cr (⭐5) - Unoffical SurrealDB HTTP & Websocket Client

Feb 21, 2023

Testing

• hashr (⭐0) - A tiny class makes test on JSON response easier

Official Documentation Translations

• procodile (⭐5) - Run processes in the background (and foreground) on Mac & Linux from a Procfile (for production and/or development environments)

• port_ruby_to_crystal (⭐9) - A regex replace ruby script for port ruby code to crystal easier, reduce friction

Feb 16, 2023

GUI Development

• Ultimate GTK4 Crystal Guide - Learn how to create premium GTK4 apps in Crystal

Feb 12, 2023

Misc

• observable (⭐9) - Implementation of the observer pattern

Editor Plugins

• Lite-XL
  • lite-plugin-crystal (⭐5) - Crystal support for the Lite-XL editor

Jan 26, 2023

Image processing

• Pluto (⭐65) - A fast and convenient image processing library

Jan 11, 2023

Web Frameworks

• Crystal Forum

Jan 05, 2023

CLI Utils

• hetzner-k3s (⭐1.3k) - A CLI tool to quickly create and manage Kubernetes clusters in Hetzner Cloud

Dec 31, 2022

Image processing

• ffmpeg (⭐18) - FFmpeg bindings that works with StumpyPNG to extract frames

Third-party APIs

• amazonite (⭐0) - An unofficial SDK supporting popular AWS APIs

Dec 18, 2022

Algorithms and Data structures

• Goban (⭐23) - A fast and efficient QR Code implementation

Nov 24, 2022

Web Frameworks

• marten (⭐378) - A web framework that makes building web applications easy, productive, and fun

Nov 17, 2022

Game Development

• SDL-Crystal-Bindings (⭐5) - Direct (unsafe) bindings to SDL2, intended for writing own game libraries

Sep 29, 2022

Cryptography

• ed25519 (⭐7) - the Ed25519 elliptic curve public-key signature system described in [RFC 8032]

Data Formats

• json-schema (⭐12) - convert JSON serializable classes into a JSON Schema representation

GUI Development

• GTK4.cr (⭐96) - Bindings for GTK4 with Crystalized API

Aug 27, 2022

Network Protocols

• mqtt-client.cr (⭐3) - A fast and lightweight MQTT client

Jul 14, 2022

Algorithms and Data structures

• csuuid (⭐15) - A Chronologically Sortable UUID

• secure-remote-password (⭐6) - SRP-6a protocol for authentication over an insecure network

Jun 05, 2022

Logging and monitoring

• fiber_metrics.cr (⭐7) - Track run time, wait time, or memory allocations per Fiber, method or block

May 03, 2022

Processes and Threads

• concurrent.cr (⭐45) - Simplified concurrency using streams/pipelines, waitgroups, semaphores, smores and more

Apr 10, 2022

Misc

• defined (⭐17) - macros for conditional compilation based on constant definitions, version requirements, or environment variable settings

Dec 28, 2021

C bindings

• fftw.cr (⭐11) - Bindings for FFTW library

• wasmer-crystal (⭐88) - Bindings for the wasmer WebAssembly runtime

Dec 09, 2021

C bindings

• nlopt.cr (⭐3) - Bindings for NLOpt

Cryptography

• monocypher.cr (⭐17) - Crystal wrapper for the Monocypher crypto library

Game Development

• MyECS (⭐19) - A Sparse Entity Component System Framework for Crystal

Nov 15, 2021

CLI Builders

• Athena Console (⭐13) - Allows for the creation of CLI based commands

HTML/XML Parsing

• docx_cr_converter (⭐6) - parse DOCX Word

Third-party APIs

• mollie.cr (⭐17) - Mollie Payments API wrapper (Creditcard, PayPal, Apple Pay, Sofort, Klarna, ...)

Oct 20, 2021

C bindings

• augeas.cr (⭐7) - Bindings for Augeas

Sep 28, 2021

Networking

• mac-address (⭐2) - Library for working with MAC addresses

Sep 27, 2021

Internationalization

• Rosetta (⭐38) - A blazing fast internationalization (i18n) library with compile-time key lookup supporting YAML and JSON formats

Aug 31, 2021

Internationalization

• Lens (⭐16) - A multiformat internationalization (i18n) shard for Crystal. Supports Gettext, Ruby YAML, etc.

Aug 26, 2021

Internationalization

• crystal-i18n (⭐23) - An internationalization library inspired by Ruby-I18n

• i18n.cr (⭐22) - Internationalization shard

Aug 05, 2021

Converters

• crunits (⭐6) - Tool for converting units of measure (miles to kilometers, celsius to fahrenheit etc)

Network Protocols

• crystal-bacnet (⭐0) - BACnet protocol implementation with BACnet/IP client

Jul 04, 2021

Third-party APIs

• tmdb.cr (⭐3) - The Movie DB (TMDb) api wrapper

Jul 03, 2021

Network Protocols

• simple_rpc (⭐65) - RPC Server and Client for Crystal. Implements msgpack-rpc protocol

Jun 28, 2021

CLI Utils

• meet (⭐38) - Start a jitsi meeting quickly from the comfort of your command line

Jun 14, 2021

Algorithms and Data structures

• crystalg (⭐37) - A Generic Algorithm Library

CLI Utils

• oq (⭐188) - A performant, and portable jq wrapper to facilitate the consumption and output of formats other than JSON; using jq (⭐29k) filters to transform the data

Dependency Injection

• HardWire (⭐21) - A compile-time non-intrusive dependency injection system

Framework Components

• mochi (⭐25) - Authentication shard inspired by Devise supporting: Authenticable, Confirmable, Invitable & more

• motion.cr (⭐53) - Object oriented frontend library for Amber

• tourmaline (⭐154) - Telegram bot framework with an API loosely based on telegraf.js

Misc

• burocracia.cr (⭐20) - burocracia.cr the dependecyless shard to validate, generate and format Brazilian burocracias such as CPF, CNPJ and CEP

ORM/ODM Extensions

• avram (⭐160) - A database wrapper for reading, writing, and migrating Postgres databases

Queues and Messaging

• mosquito (⭐219) - Redis backed periodic and ad hoc job processing

Serverless Computing

• secrets-env (⭐6) - Extends ENV module to read values injected by docker / kubernetes secrets and other orchestration tools

Editor Plugins

• Geany
  • geany-crystal (⭐8) - Crystal support for the Geany editor

LSP Language Server Protocol Implementations

• crystalline (⭐410) - Crystalline is an implementation of the Language Server Protocol written in and for the Crystal Language

May 27, 2021

Compression

• Gzip - readers and writers of gzip format (Crystal stdlib)

• Zip - readers and writers of zip format (Crystal stdlib)

• Zlib - readers and writers of zlib format (Crystal stdlib)

Apr 24, 2021

CLI Utils

• coin (⭐6) - Command-line application that performs currency conversion via the Fixer API

Apr 22, 2021

Algorithms and Data structures

• splay_tree_map (⭐14) - Splay Tree implementation that conforms to the Hash ducktype

Debugging

• backtracer.cr (⭐15) - Shard aiming to assist with parsing backtraces into a structured form

• debug.cr (⭐93) - debug!(…) macro for pp-style debugging

Misc

• serf-handler.cr (⭐1) - Framework for building Serf handlers, with a suite of useful builtin capabilities

Apr 21, 2021

Network Protocols

• stomp (⭐1) - STOMP protocol

Apr 12, 2021

Algorithms and Data structures

• s2_cells (⭐0) - S2 Geometry for spatial indexing

HTTP

• link-header (⭐1) - HTTP Link Header Parser

Mar 01, 2021

Editor Plugins

• Acme:
  • acmecrystal (⭐6) - Reformats crystal code in acme

• Emacs
  • crystal-mode - Crystal language support for Emacs (crystal-lang-tools/emacs-crystal-mode (⭐45))

Feb 27, 2021

Misc

• anyolite (⭐157) - Full mruby interpreter with simple bindings, allowing for easy scripting support in projects

Feb 01, 2021

Framework Components

• Athena Negotiation (⭐4) - Framework agnostic content negotiation library

Testing

• Athena Spec (⭐2) - Common/helpful Spec compliant testing utilities

Dec 19, 2020

LSP Language Server Protocol Implementations

• scry (⭐331) - Code analysis server for Crystal implementing the Language Server Protocol

Dec 08, 2020

Algorithms and Data structures

• qr-code (⭐17) - QR Code generator

Dec 07, 2020

Image processing

• celestine (⭐90) - Create SVG images using a DSL

Nov 03, 2020

Data Formats

• Crystalizer (⭐39) - (De)serialize any Crystal object; supporting JSON, YAML, and Byte formats out of the box

Nov 02, 2020

Blockchain

• Axentro (⭐193) - A custom blockchain platform

Validation

• Athena Validator (⭐5) - Robust & flexible validation framework

Official Documentation Translations

• Invidious (⭐15k) - Invidious is an alternative front-end to YouTube

Nov 01, 2020

Misc

• sslscan.cr (⭐10) - Crystal shard wrapping the rbsec/sslscan utility

Processes and Threads

• werk (⭐25) - Dead simple task runner with concurrent support, ideal for local CI

Oct 31, 2020

Network Protocols

• mDNS (⭐8) - DNS Service Discovery and multicast DNS

Oct 18, 2020

Configuration

• Envy (⭐7) - Load environment variables from YAML

Oct 16, 2020

Web Frameworks

• grip (⭐272) - The microframework for writing powerful web applications

Sep 26, 2020

Compression

• polylines.cr (⭐9) — compression of series of coordinates

Sep 21, 2020

Framework Components

• Shield (⭐53) - Comprehensive security for Lucky framework

Misc

• wafalyzer (⭐32) - Web Application Firewall (WAF) Detector - shard + cli

Sep 08, 2020

Game Development

• crystal-chipmunk (⭐42) - Bindings to Chipmunk, a fast and lightweight 2D game physics library

• crystal-imgui-sfml (⭐16) - Bindings to integrate Dear ImGui (⭐55k) into an SFML project

GUI Development

• crystal-imgui (⭐64) - Bindings to Dear ImGui (⭐55k), an immediate-mode graphical UI library

Sep 04, 2020

HTTP

• ntlm (⭐4) - NTLM authentication

Aug 23, 2020

GUI Development

• Iu (⭐67) - UI framework based on the Fusion/libui.cr (⭐176) library, with custom elements and modified bindings from hedron-crystal/hedron (⭐84)

HTTP

• digest-auth (⭐4) - Digest authentication

Aug 20, 2020

Framework Components

• graphql (⭐133) - Type-safe GraphQL server implementation

• graphql-crystal (⭐215) - GraphQL implementation

Unofficial

• crystal-koans (⭐46) - Learn Crystal by writing unit tests

Jul 27, 2020

Database Drivers/Clients

• cryomongo (⭐67) - MongoDB driver

Jul 14, 2020

Misc

• version_tools (⭐8) - Version-dependent behaviour, specified at compile-time

Jun 30, 2020

Science and Data analysis

• alea (⭐12) - Repeatable sampling, CDF and other utilities to work with probability distributions

Jun 24, 2020

CLI Utils

• climate (⭐14) - Tiny tool to make your CLI output 🌈 coloured

Jun 19, 2020

CLI Utils

• lff (⭐17) - Simple and straightforward large files finder utility in command line

Database Drivers/Clients

• crystal-ldap (⭐16) - LDAP client

Jun 14, 2020

Network Protocols

• crystal-mqtt (⭐19) - A MQTT client

Jun 10, 2020

Dependency Injection

• Athena Dependency Injection (⭐9) - Robust dependency injection service container framework

Framework Components

• Athena Event Dispatcher (⭐13) - A Mediator and Observer pattern event library

Web Frameworks

• Athena (⭐200) - A web framework comprised of reusable, independent components

Jun 08, 2020

Official Documentation Translations

• Crank (⭐50) - A Procfile-based application manager (like Foreman)

Jun 01, 2020

Code Analysis and Metrics

• linguist.cr (⭐7) - Using multiple ways to find programming language used in files, based on Github's Linguist

Misc

• simple_retry (⭐6) - Simple tool for retrying failed code blocks

Third-party APIs

• stripe.cr (⭐48) - Stripe api wrapper

May 25, 2020

Web Frameworks

• runcobo (⭐49) - An api framework with simple, intuitive and consistent DSL, using jbuilder to render json

May 18, 2020

Algorithms and Data structures

• blurhash.cr (⭐22) - BlurHash (⭐15k) implementation

May 07, 2020

Email

• sendgrid.cr (⭐16) - Simple Sendgrid Client

Environment Management

• crenv (⭐236) - Crystal version manager

May 04, 2020

Game Development

• entitas.cr (⭐36) - A Entity Component System Framework for Crystal

Apr 30, 2020

Science and Data analysis

• quartz (⭐15) - Modeling and simulation framework

Apr 26, 2020

Misc

• gphoto2-web.cr (⭐8) - Web API for libgphoto2

Apr 15, 2020

Logging and monitoring

• Log - logging utility (Crystal stdlib)

Apr 05, 2020

CLI Builders

• Keimeno (⭐14) - A lightweight text user interface library in Crystal

Apr 04, 2020

Third-party APIs

• google (⭐24) - Google API wrapper

• office365 (⭐8) - Microsoft Graph API wrapper

Apr 03, 2020

Data Generators

• prime (⭐1) - A prime number generator

Mar 30, 2020

Machine Learning

• mxnet.cr (⭐22) - Bindings for MXNet

Misc

• iterm2 (⭐6) - Display images within the terminal using the ITerm2 Inline Images Protocol

Science and Data analysis

• ishi (⭐47) - Graph plotting package with a small API and sensible defaults powered by gnuplot

Third-party APIs

• host_meta (⭐3) - A Web Host Metadata (https://tools.ietf.org/html/rfc6415) client

• web_finger (⭐9) - A WebFinger (https://tools.ietf.org/html/rfc7033) client

Official Documentation Translations

• public_suffix (⭐2) - A small library designed to make the Public Suffix List (https://publicsuffix.org/) easier to use

Mar 27, 2020

Network Protocols

• amqp-client.cr (⭐66) - AMQP 0-9.1, a messaging protocol, implemented by eg. RabbitMQ

Mar 23, 2020

Web Frameworks

• Shivneri (⭐22) - Component based MVC web framework for crystal targeting good code structures, modularity & performance

Mar 14, 2020

Validation

• validator (⭐29) - Data check and validation

Mar 12, 2020

Unofficial

• Portuguese-speaking Telegram Group - Bem vindos ao Crystal Brasil!

Feb 26, 2020

Algorithms and Data structures

• fzy (⭐44) - A Crystal port of awesome Fzy project fuzzy finder algorithm

Feb 06, 2020

HTML Builders

• Water (⭐26) - A library for writing HTML in plain Crystal

Feb 02, 2020

Network Protocols

• crystal-dns - DNS protocol implementation and resolver

Feb 01, 2020

Cryptography

• cmac (⭐5) - Crystal implementation of Cipher-based Message Authentication Code (CMAC)

Jan 27, 2020

Blockchain

• Cocol (⭐19) - A minimal blockchain testbed

• secp256k1.cr (⭐48) - Elliptic curve used in the public-private-key cryptography

Jan 10, 2020

Shell plugins

• crystal-zsh (⭐28) - .oh-my-zsh plugin

Jan 06, 2020

Data Formats

• JSON::OnSteroids (⭐23) - handle and mutate JSON document easily

Jan 04, 2020

Algorithms and Data structures

• haversine (⭐17) - An Implementation of the Haversine formula

• kd_tree (⭐17) - An implementation of "K-Dimensional Tree" and "N-Nearest Neighbors"

Machine Learning

• Cadmium (⭐201) - NLP library based heavily on natural (⭐10k)

Dec 30, 2019

Misc

• CrSignals (⭐10) - Signals/slots notification library

Dec 10, 2019

Data Formats

• HAR (⭐22) - HAR (HTTP Archive) parser

Science and Data analysis

• num.cr (⭐145) - Numerical computing library supporting N-Dimensional data

Dec 09, 2019

Framework Components

• shrine.cr (⭐73) - File Attachment toolkit for Crystal applications. Heavily inspired by Shrine for Ruby

Dec 02, 2019

Unofficial

• Crystal Programming Discord Server - Unofficial Discord server dedicated to the Crystal Programming Language

Nov 03, 2019

Template Engine

• Jbuilder (⭐44) - Generate JSON objects with a Builder-style DSL, inspired by jbuilder

Nov 02, 2019

C bindings

• clang.cr (⭐46) - Libclang bindings

CLI Builders

• Phreak (⭐32) - A highly flexible Crystal CLI builder in the style of OptionParser

Dependency Injection

• Crystal-DI (⭐31) - Lightweight DI Container

• syringe (⭐6) - A simple and basic dependency injection shard for crystal

Oct 28, 2019

HTTP

• proxy-fetcher.cr (⭐9) - Proxy lists fetching & validating library

Oct 25, 2019

Compression

• Crystar (⭐38) - Readers and writers of Tar archive format

• snappy (⭐18) - Snappy compression format reader/writer for Crystal

• zstd.cr (⭐39) - Bindings for Zstandard (⭐22k) compression library

Oct 18, 2019

ORM/ODM Extensions

• crecto (⭐342) - Database wrapper, based on Ecto

Oct 14, 2019

Algorithms and Data structures

• crie (⭐12) - Compile-time Trie

Oct 12, 2019

Network Protocols

• connect-proxy (⭐6) - Connect method style of HTTP tunnelling / HTTP proxy

Oct 08, 2019

CLI Utils

• tablo (⭐27) - A flexible terminal table generator

Misc

• zaru_crystal (⭐9) - Filename sanitization

Oct 05, 2019

Network Protocols

• telnet.cr (⭐11) - Telnet protocol

Sep 27, 2019

Network Protocols

• Crirc (⭐21) - IRC protocol implementation (Client, Server, Bots)

Sep 25, 2019

Network Protocols

• cr-xmpp (⭐16) - XMPP/Jabber Library

Sep 13, 2019

Queues and Messaging

• NATS.io (⭐44) - NATS client

Sep 03, 2019

Third-party APIs

• crystal-consul (⭐17) - Consul API client

Sep 02, 2019

Unofficial

• Chinese-speaking Telegram Group - 来吧！TG 中文圈的朋友们！

Aug 01, 2019

Code Analysis and Metrics

• ameba (⭐500) - A static code analysis tool

Jul 30, 2019

HTTP

• Cable (⭐121) - An ActionCable "port" to Crystal, framework agnostic, 100% compatible with the ActionCable JS Client

Jul 15, 2019

Logging and monitoring

• crafana (⭐21) - A Grafana library to help autogenerate dashboards

Misc

• monads (⭐46) - Monad implementation

Testing

• vcr (⭐58) - A HTTP capture and replay implementation for crystal

Third-party APIs

• kube-client.cr (⭐21) - Kubernetes API Client

Jun 29, 2019

Cryptography

• sodium.cr (⭐46) - Crystal wrapper for the libsodium crypto API

Jun 25, 2019

HTTP

• sse.cr (⭐20) - Server-Sent Events client

Jun 17, 2019

Misc

• pinger (⭐11) - Ping IP addresses and DNS entries without requiring sudo

Third-party APIs

• ynab.cr (⭐4) - A library to interact with your YNAB data

May 21, 2019

Testing

• spectator - Feature rich spec framework that uses the modern expect syntax

May 20, 2019

Misc

• port_midi (⭐5) - Crystal C bindings for the PortMIDI cross-platform MIDI I/O library

May 17, 2019

Network Protocols

• crystal-snmp (⭐16) - An SNMP implementation with version 1, 2c and 3 support

May 11, 2019

C bindings

• crystal-hunspell (⭐6) - Bindings for Hunspell

Apr 26, 2019

Misc

• crystal-web-framework-stars (⭐68) - Web frameworks for Crystal, most starred on Github

Apr 08, 2019

ORM/ODM Extensions

• rethinkdb-orm (⭐24) - ORM for RethinkDB / RebirthDB

Apr 05, 2019

CLI Utils

• tallboy (⭐53) - Generate ASCII character tables with support for spanning cells over multiple columns

Apr 03, 2019

HTML Builders

• form_builder.cr (⭐31) - Dead simple HTML form builder for Crystal with built-in support for many popular UI libraries such as Bootstrap

Mar 15, 2019

Data Formats

• BinData (⭐48) - Binary data parser helper with an ASN.1 parser

Mar 05, 2019

Email

• CrystalEmail - A RFC compliant Email validator

Network Protocols

• transfer_more - Clone of transfer.sh to uploads files

Feb 20, 2019

C bindings

• ssh2.cr (⭐42) - Bindings for libssh2 library

HTTP

• http-params-serializable (⭐21) - HTTP params (de)serialization, applicable to URL queries and URL-encoded forms

Feb 15, 2019

Testing

• webdriver_pump (⭐4) - Page Object library. Inspired by Ruby's WatirPump (⭐16)

Feb 11, 2019

Database Drivers/Clients

• crystal-rethinkdb (⭐22) - Driver for RethinkDB / RebirthDB

Feb 10, 2019

Data Formats

• geoip2.cr (⭐16) - GeoIP2 reader

• maxminddb.cr (⭐23) - MaxMindDB reader

Feb 02, 2019

Examples and funny stuff

• blackjack-cr (⭐8) - Console Blackjack

Jan 09, 2019

Algorithms and Data structures

• graphlb (⭐19) - Collection of graph datastructure and algorithms

Jan 07, 2019

Testing

• crytic (⭐65) - Mutation testing framework

Dec 28, 2018

Framework Components

• praetorian (⭐58) - Minimalist authorization library inspired by Pundit

Nov 25, 2018

Testing

• timecop.cr (⭐19) - Library for mocking with Time.now. Inspired by the timecop ruby gem (⭐3.3k)

Oct 29, 2018

Official Documentation Translations

• ast_helper (⭐25) - Helper tool to debug parser and formatter

Oct 21, 2018

Database Drivers/Clients

• couchdb.cr (⭐12) - CouchDB client

Oct 17, 2018

Serverless Computing

• crystal_openfaas (⭐22) - Template to enable crystal as first class citizens in OpenFaaS

Official Documentation Translations

• shards.info - Web service that lists all repositories on GitHub that have Crystal code in them. The sources are available on GitHub (⭐40)

Oct 02, 2018

Data Formats

• toml.cr (⭐58) - TOML parser

Sep 26, 2018

Unofficial

• Crystal for Rubyists - Free book to bootstrap your Crystal journey

• Programming Crystal - PragProg book to start your Crystal journey

Sep 24, 2018

Examples and funny stuff

• crystalworld (⭐42) - realworld.io back-end API implementation

Sep 20, 2018

Validation

• accord (⭐25) - Shareable validation library for Crystal Objects

• validations (⭐13) - Validations mixin

Sep 19, 2018

Configuration

• envyable (⭐6) - A simple YAML to ENV config loader

Misc

• callbacks (⭐12) - Expressive callbacks module

Official Documentation Translations

• quicktype - Generate models and serializers from JSON, JSON Schema, GraphQL, and TypeScript

Sep 15, 2018

HTML/XML Parsing

• myhtml (⭐152) - Fast HTML5 Parser that includes CSS selectors

Sep 05, 2018

Algorithms and Data structures

• CrOTP (⭐62) - HOTP and TOTP implementation for two factor authentication

Sep 03, 2018

Misc

• retriable.cr (⭐38) - Simple DSL to retry failed code blocks

DevOps

• DPPM (⭐113) - An easy, universal way to install and manage applications as packages (mostly Linux)

Sep 02, 2018

Algorithms and Data structures

• ksuid.cr (⭐15) - K-Sortable Globally Unique IDs

Aug 24, 2018

C bindings

• syslog.cr (⭐10) - Bindings for syslog

Aug 21, 2018

Algorithms and Data structures

• bisect (⭐12) - Inserting values into a sorted array

Processes and Threads

• promise (⭐40) - A Promise implementation with type inference

Scheduling

• tasker (⭐54) - A high precision scheduler including timezone aware cron jobs

Shell plugins

• crun (⭐43) - Crystal Run : shebang wrapper for Crystal

Aug 08, 2018

Configuration

• totem (⭐65) - Load and parse a configuration in JSON, YAML, dotenv formats

Aug 01, 2018

Processes and Threads

• await_async (⭐81) - Add keywords await & async in Crystal Lang

Jul 31, 2018

Network Protocols

• crystal-json-socket (⭐13) - JSON-socket client & server implementation. Inspired by and compatible with node-json-socket (⭐155) and ruby-json-socket (⭐4)

Jul 29, 2018

Converters

• base62.cr (⭐9) - Base62 encoder/decoder, well suited for url-shortening

Jul 25, 2018

CLI Utils

• cride (⭐49) - A light CLI text editor/IDE

Jul 11, 2018

Implementations/Compilers

• LinCAS-lang - A programming language for scientific computation

Jun 30, 2018

Framework Components

• Exception Page (⭐63) - An exceptional exception page for Crystal web libraries and frameworks

Jun 28, 2018

Testing

• mass-spec (⭐8) - Web API testing library

Jun 22, 2018

CLI Builders

• clicr (⭐29) - A simple declarative command line interface builder

Jun 21, 2018

Converters

• money (⭐29) - Handling money and currency conversion with ease (almost complete port of RubyMoney (⭐2.7k))

Jun 20, 2018

Unofficial

• Russian-speaking Telegram Group - Добро пожаловать, товарищ!

Jun 18, 2018

Framework Components

• device_detector (⭐22) - Shard for detect device by user agent string

Official Documentation Translations

• mpngin (⭐32) - A URL shortener with simple stats

Jun 04, 2018

Scheduling

• crystime - Advanced time, calendar, schedule, and remind library

May 30, 2018

Data Formats

• config.cr (⭐14) - Easy to use configuration format parser

• front_matter.cr (⭐11) - Separates a files front matter from its content

May 19, 2018

Testing

• LuckyFlow (⭐50) - Automated browser tests similar to Capybara

May 10, 2018

System

• baked_file_system (⭐175) - Virtual file system implementation

• hardware (⭐71) - Get CPU, Memory and Network informations of the running OS and its processes

Apr 27, 2018

Implementations/Compilers

• mint-lang (⭐4k) - A refreshing programming language for the front-end web

• runic-lang - In-design toy language

Apr 08, 2018

ORM/ODM Extensions

• granite (⭐293) - ORM for Postgres, Mysql, Sqlite

Apr 07, 2018

Email

• carbon (⭐83) - Fun, testable, and adapter-based email library

Mar 14, 2018

Data Formats

• crinder (⭐28) - Class based json renderer

HTTP

• halite (⭐172) - Crystal HTTP Requests with a chainable REST API, built-in sessions and loggers

Mar 06, 2018

CLI Builders

• OptionParser - command-line options processing (Crystal stdlib)

Data Formats

• CSV - parsing and generating for comma-separated values (Crystal stdlib)

• INI - INI file parser (Crystal stdlib)

• JSON - parsing and generating JSON documents (Crystal stdlib)

• XML - parsing and generating XML documents (Crystal stdlib)

• YAML - parsing and generating YAML documents (Crystal stdlib)

HTTP

• HTTP::Client - HTTP client (Crystal stdlib)

• HTTP::Server - HTTP server (Crystal stdlib)

• HTTP::WebSocket - HTTP WebSocket client (Crystal stdlib)

Network Protocols

• OAuth - OAuth consumer (Crystal stdlib)

• OAuth2 - OAuth2 client (Crystal stdlib)

• OpenSSL - bindings to libssl (Crystal stdlib)

Networking

• ipaddress.cr (⭐42) - Library to handle IPv4 and IPv6 addresses

Template Engine

• ECR (Embedded Crystal) - compile time template language which uses plain crystal expressions (Crystal stdlib)

Testing

• Spec - spec framework (Crystal stdlib)

Mar 01, 2018

Third-party APIs

• twitter-crystal (⭐83) - A library to access the Twitter API

Feb 19, 2018

Web Frameworks

• spider-gazelle (⭐175) - A Rails esque web framework with a focus on speed and extensibility

Feb 18, 2018

C bindings

• pledge.cr (⭐8) - Bindings for OpenBSD's pledge(2)

Feb 02, 2018

C bindings

• x_do.cr (⭐18) - Bindings for libxdo (xdotool)

Jan 27, 2018

Routing

• orion (⭐122) - A minimal, rails-esque routing library

Jan 10, 2018

Database Tools

• migrate (⭐31) - A simpler database migration tool with transactions

Jan 05, 2018

Official Documentation Translations

• cry (⭐34) - Ability to execute crystal code in a fashion similar to Ruby's pry edit

Dec 24, 2017

Machine Learning

• shainet (⭐178) - SHAInet (Neural Network in pure crystal)

Dec 04, 2017

ORM/ODM Extensions

• clear (⭐268) - ORM specialized to PostgreSQL only but with advanced features

Nov 24, 2017

Unofficial

• devdocs.io - API Documentation Browser with Crystal support

Nov 22, 2017

Configuration

• habitat (⭐81) - Type safe configuration for your classes and modules

Web Frameworks

• lucky (⭐2.5k) - Catch bugs early, forget about most performance issues, and spend more time on code instead of debugging and writing tests

Oct 23, 2017

HTTP

• crest (⭐230) - Simple HTTP and REST client, inspired by the Ruby's RestClient gem

Oct 22, 2017

DevOps

• ansible-crystal (⭐9) - Ansible playbook for installing crystal

Oct 19, 2017

Third-party APIs

• GDAX (⭐7) - GDAX REST and WebSocket API Wrapper with request signing

Oct 18, 2017

Third-party APIs

• mixpanel-crystal (⭐0) - A library for sending events to Mixpanel

Oct 04, 2017

Algorithms and Data structures

• markov (⭐21) - Build Markov Chains and run Markov Processes

Oct 03, 2017

Machine Learning

• ai4cr (⭐27) - Artificial Intelligence (based on https://github.com/SergioFierens/ai4r (⭐713))

Oct 02, 2017

Examples and funny stuff

• crystal-patterns (⭐291) - Examples of GOF patters

Sep 22, 2017

Markdown/Text Processors

• markd (⭐107) - Yet another markdown parser built for speed, Compliant to CommonMark specification

Sep 17, 2017

Machine Learning

• crystal-fann (⭐80) - FANN (Fast Artifical Neural Network) binding

Sep 15, 2017

Web Frameworks

• amber (⭐2.5k) - Open source efficient and cohesive web application framework

Sep 10, 2017

HTTP

• http-multiserver.cr (⭐23) - Mounting multiple servers via routes (a.k.a. URL mapping)

Sep 08, 2017

Official Documentation Translations

• crystal-base (⭐2) - CentOS base docker image for Crystal development

Aug 22, 2017

Database Drivers/Clients

• leveldb (⭐38) - Crystal bindings for LevelDB

Examples and funny stuff

• exercism-crystal (⭐75) - Exercism exercises

Game Development

• CrSFML (⭐342) - Bindings to SFML multimedia/game library

HTTP

• cossack (⭐105) - Simple flexible HTTP client

Image processing

• stumpy_png (⭐103) - Read and write PNG images

Network Protocols

• jwt (⭐204) - Implementation of JWT (JSON Web Token)

• msgpack-crystal (⭐133) - MessagePack library

Package Management

• shards (⭐750) - Dependency manager for the Crystal

Web Frameworks

• kemal (⭐3.6k) - Lightning Fast, Super Simple web framework. Inspired by Sinatra

• Reddit

• Stackoverflow

Unofficial

• crystal-lang.org - Official language site

Official Documentation Translations

• icr (⭐501) - Interactive console for Crystal (like IRB for Ruby)

Editor Plugins

• Sublime
  • sublime-crystal (⭐83) - Crystal syntax highlighting for sublime Text

• TextMate
  • Crystal.tmbundle (⭐19) - Crystal syntax highlighting, compile, format command, snippets

• Vim
  • vim-crystal (⭐411) - Vim filetype support for Crystal
  • vim-slang (⭐12) - Vim filetype support for Slang Templating Engine

• Visual Studio Code
  • vscode-crystal-lang (⭐269) - Formatter, linter and syntax highlighting for cr and ecr files

Aug 12, 2017

Testing

• microtest (⭐30) - Small opinionated testing library focusing on power asserts

Aug 03, 2017

ORM/ODM Extensions

• jennifer.cr (⭐410) - Active Record pattern implementation with flexible query chainable builder and migration system

Aug 01, 2017

Implementations/Compilers

• myst-lang - A practical, dynamic language designed to be written and understood as easily and efficiently as possible

Jul 30, 2017

Third-party APIs

• pinboard.cr (⭐5) - Pinboard API

Jul 16, 2017

Official Documentation Translations

• Crystal [ANN] - Announce new project, blog post, version update or any other Crystal work

Jul 14, 2017

Third-party APIs

• awscr-s3 (⭐80) - AWS S3 interface

Jul 13, 2017

Converters

• sass.cr (⭐35) - Compile SASS/SCSS to CSS (libsass (⭐4.3k) binding)

Email

• crystal-email (⭐110) - Simple e-mail sending library

Jul 12, 2017

Science and Data analysis

• linalg (⭐46) - Linear algebra library inspired by MATLAB and SciPy.linalg

Jun 23, 2017

CLI Utils

• progress_bar.cr (⭐15) - A simple and customizable progress bar

Jun 01, 2017

Template Engine

• crinja (⭐118) - An implementation of the Jinja2 template engine

May 28, 2017

Framework Components

• multi-auth (⭐111) - Standardized multi-provider OAuth2 authentication (inspired by omniauth)

May 23, 2017

Scheduling

• schedule.cr (⭐73) - Run periodic tasks

May 15, 2017

CLI Builders

• clim (⭐118) - Slim command line interface builder

May 14, 2017

C bindings

• icu.cr (⭐11) - Bindings for the ICU library

Project Generators

• libgen (⭐76) - Automatic bindings generator configured using JSON/YAML files

May 13, 2017

Task management

• cake (⭐70) - Production-ready Make-like utility tool

May 10, 2017

Implementations/Compilers

• cltk (⭐72) - A crystal port of the Ruby Language Toolkit

May 09, 2017

Routing

• router.cr (⭐259) - Minimum but powerful http router for HTTP::Server

May 08, 2017

C bindings

• crt.cr (⭐27) - Bindings for libncursesw and crt

• duktape.cr (⭐134) - Bindings for the Duktape (⭐5.8k) javascript engine

• gphoto2.cr (⭐15) - Bindings for the libgphoto2 library

• libnotify.cr (⭐25) - Bindings for Libnotify

• pcap.cr (⭐24) - Bindings for libpcap

Logging and monitoring

• statsd.cr (⭐33) - Statsd (⭐17k) client library

Processes and Threads

• neph (⭐202) - A modern command line job processor that can execute jobs concurrently

Apr 23, 2017

Official Documentation Translations

• crystal-dash-docset (⭐17) - Dash docset generator

Apr 10, 2017

Misc

• crz (⭐90) - Functional programming library

Apr 01, 2017

Framework Components

• kemal-session (⭐51) - Session handler for Kemal

Mar 30, 2017

Third-party APIs

• crystal-darksky (⭐8) - Wrapper for the Dark Sky API

Mar 29, 2017

Third-party APIs

• crystal-swapi (⭐4) - Star Wars API (SWAPI) wrapper

Mar 21, 2017

Search

• hermes (⭐37) - Data Mapper pattern implementation for ElastiSearch

Task management

• sam (⭐93) - Another one Rake-like task manager with namespacing and arguments system

Mar 20, 2017

HTTP

• http-protection (⭐71) - Protection against typical web attacks

Feb 28, 2017

Third-party APIs

• raven.cr (⭐118) - Raven is a client for Sentry (⭐37k)

Feb 18, 2017

Official Documentation Translations

• kr.crystal-lang.org - Korean

Feb 17, 2017

Misc

• any_hash.cr (⭐35) - Recursive Hash with better JSON::Any included

Feb 08, 2017

Implementations/Compilers

• charly - Charly Programming Language

Feb 01, 2017

CLI Builders

• admiral (⭐134) - A robust DSL for writing command line interfaces

Jan 21, 2017

Environment Management

• asdf-crystal (⭐73) - Plugin for asdf version manager

Jan 12, 2017

Third-party APIs

• awscr-signer (⭐22) - Sign HTTP::Request objects and generate presigned post forms

Dec 14, 2016

Misc

• crystal-binary_parser (⭐18) - Binary parser

Dec 06, 2016

Science and Data analysis

• predict.cr (⭐17) - Satellite prediction library using the sgp4 model

Dec 04, 2016

Database Drivers/Clients

• rocksdb.cr (⭐37) - RocksDB client

Nov 16, 2016

Examples and funny stuff

• try.cr (⭐26) - Try monad

Sep 29, 2016

Database Drivers/Clients

• crystal-mysql (⭐106) - MySQL connector for Crystal

• crystal-sqlite3 (⭐131) - SQLite3 bindings

Sep 07, 2016

Editor Plugins

• Spacemacs
  • crystal-spacemacs-layer (⭐12) - Spacemacs contribution layer for Crystal

Sep 06, 2016

Template Engine

• teeplate (⭐16) - A library for rendering multiple template files

Aug 23, 2016

Algorithms and Data structures

• crystal-linked-list (⭐12) - Implementation of Linked List

Aug 10, 2016

Project Generators

• crystal_lib (⭐138) - Automatic binding generator for native libraries

Template Engine

• Kilt (⭐150) - Abstraction layer for template engines

• Slang (⭐233) - Lightweight, terse, templating language inspired by Ruby's Slim

Aug 08, 2016

Configuration

• cr-dotenv (⭐93) - Loads .env file

Web Frameworks

• Gitter

Aug 01, 2016

Data Generators

• hashids.cr (⭐52) - A library to generate YouTube-like ids from one or many numbers

Jul 25, 2016

Project Generators

• fez (⭐49) - A Kemal application generator

Jul 21, 2016

Network Protocols

• fast_irc.cr (⭐22) - Fast IRC parser/generator

Jul 08, 2016

Database Drivers/Clients

• crystal-db (⭐294) - Common db api

Jun 21, 2016

Environment Management

• rcm.cr (⭐45) - Redis Cluster Manager

Jun 16, 2016

Third-party APIs

• gitlab.cr (⭐29) - GitLab API wrapper

Official Documentation Translations

• br.crystal-lang.org - Brazilian

• ja.crystal-lang.org - Japanese

• ru.crystal-lang.org - Russian

• tw.crystal-lang.org - Chinese Traditional

Jun 15, 2016

Algorithms and Data structures

• edits.cr (⭐16) - Collection of edit distance algorithms

Jun 10, 2016

Algorithms and Data structures

• crystaledge (⭐26) - A pure Vector Math library

Third-party APIs

• aws-signer.cr (⭐13) - This library signs your HTTP requests using AWS v4

May 28, 2016

CLI Builders

• commander (⭐124) - Command-line interface builder

May 26, 2016

Misc

• circuit_breaker (⭐27) - Implementation of the circuit breaker pattern

Queues and Messaging

• sidekiq.cr (⭐764) - Simple, efficient job processing

May 04, 2016

Algorithms and Data structures

• crystalline (⭐127) - A collection of containers and algorithms

• multiset.cr (⭐4) - Implementation of a multiset

• radix (⭐101) - Radix Tree implementation

HTTP

• http2 (⭐93) - HTTP/2 Protocol Implementation

Template Engine

• crustache (⭐82) - {{Mustache}} for Crystal

Mar 27, 2016

Misc

• immutable (⭐201) - Implementation of thread-safe, persistent, immutable collections

Testing

• crotest (⭐27) - A tiny and simple test framework

Feb 29, 2016

Implementations/Compilers

• crisp (⭐43) - Lisp dialect implemented with Crystal

Feb 06, 2016

Misc

• aasm.cr (⭐50) - Easy to use finite state machine for Crystal classes

Jan 20, 2016

Official Documentation Translations

• carc.in - A web service that runs your code and displays the result

Jan 18, 2016

Data Generators

• faker (⭐144) - A library for generating fake data

Dec 27, 2015

Database Drivers/Clients

• crystal-redis (⭐379) - Full featured Redis client

Misc

• emoji.cr (⭐47) - Emoji library

Testing

• minitest.cr (⭐144) - Library for unit tests and assertions

Jul 20, 2015

Testing

• mocks.cr (⭐50) - Mocking library for Crystal

Jul 12, 2015

Official Documentation Translations

• DeBot (⭐35) - IRC bot written in Crystal

Jun 24, 2015

Caching

• crystal-memcached (⭐34) - Implementation of a memcached client

Database Drivers/Clients

• crystal-pg (⭐459) - A Postgres driver

HTTP

• crul (⭐112) - Command line HTTP client

Testing

• webmock.cr (⭐102) - Library for stubbing HTTP::Client requests

Third-party APIs

• crystal_slack (⭐19) - A tool that parses Slack slash commands or send incoming web hooks

Editor Plugins

• Atom
  • crystal-tools - Enables built in tools in Crystal compiler
  • language-crystal-actual - Crystal language support in Atom