awesome-awesomeness/terminal/crystal2

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                                                                                                  Awesome Crystal
!Awesome (https://awesome.re/badge.svg) (https://awesome.re)

A curated list of awesome Crystal code and resources. Inspired by awesome (https://github.com/sindresorhus/awesome) and awesome-awesomeness (https://github.com/bayandin/awesome-awesomeness).
The goal is to have projects mostly stable and useful for the community.

Search shards at shards.info (https://shards.info) or follow announcements Crystal ANN  (https://crystal-ann.com) for more.

Contributions are welcome. Please take a quick look at the contribution guidelines (https://github.com/veelenga/awesome-crystal/blob/master/.github/CONTRIBUTING.md) first.

⟡ Awesome Crystal (#awesome-crystal)
  ⟡ Algorithms and Data structures (#algorithms-and-data-structures)
  ⟡ Blockchain (#blockchain)
  ⟡ C Bindings (#c-bindings)
  ⟡ Caching (#caching)
  ⟡ CLI Builders (#cli-builders)
  ⟡ CLI Utils (#cli-utils)
  ⟡ Code Analysis and Metrics (#code-analysis-and-metrics)
  ⟡ Compression (#compression)
  ⟡ Configuration (#configuration)
  ⟡ Converters (#converters)
  ⟡ Cryptography (#cryptography)
  ⟡ Data Formats (#data-formats)
  ⟡ Data Generators (#data-generators)
  ⟡ Database Drivers/Clients (#database-driversclients)
  ⟡ Database Tools (#database-tools)
  ⟡ Debugging (#debugging)
  ⟡ Dependency Injection (#dependency-injection)
  ⟡ Email (#email)
  ⟡ Environment Management (#environment-management)
  ⟡ Examples and funny stuff (#examples-and-funny-stuff)
  ⟡ Framework Components (#framework-components)
  ⟡ Game Development (#game-development)
  ⟡ GUI Development (#gui-development)
  ⟡ HTML Builders (#html-builders)
  ⟡ HTML/XML parsing (#htmlxml-parsing)
  ⟡ HTTP (#http)
  ⟡ Image Processing (#image-processing)
  ⟡ Implementations/Compilers (#implementationscompilers)
  ⟡ Internationalization (#internationalization)
  ⟡ Logging and monitoring (#logging-and-monitoring)
  ⟡ Machine Learning (#machine-learning)
  ⟡ Markdown/Text Processors (#markdowntext-processors)
  ⟡ Misc (#misc)
  ⟡ Network Protocols (#network-protocols)
  ⟡ Networking (#networking)
  ⟡ ORM/ODM Extensions (#ormodm-extensions)
  ⟡ Package Management (#package-management)
  ⟡ Processes and Threads (#processes-and-threads)
  ⟡ Project Generators (#project-generators)
  ⟡ Queues and Messaging (#queues-and-messaging)
  ⟡ Routing (#routing)
  ⟡ Scheduling (#scheduling)
  ⟡ Science and Data analysis (#science-and-data-analysis)
  ⟡ Search (#search)
  ⟡ Serverless Computing (#serverless-computing)
  ⟡ System (#system)
  ⟡ Task management (#task-management)
  ⟡ Template Engine (#template-engine)
  ⟡ Testing (#testing)
  ⟡ Third-party APIs (#third-party-apis)
  ⟡ Validation (#validation)
  ⟡ Web Frameworks (#web-frameworks)
⟡ Community (#community)
  ⟡ Unofficial (#unofficial)
⟡ Resources (#resources)
  ⟡ Official Documentation Translations (#official-documentation-translations)
⟡ Services and Apps (#services-and-apps)
⟡ Tools (#tools)
  ⟡ DevOps (#devops)
  ⟡ Editor Plugins (#editor-plugins)
  ⟡ LSP Language Server Protocol Implementations (#lsp-language-server-protocol-implementations)
  ⟡ Shell Plugins (#shell-plugins)

Algorithms and Data structures
 ⟡ bisect (https://github.com/spider-gazelle/bisect) - Inserting values into a sorted array
 ⟡ blurhash.cr (https://github.com/Sija/blurhash.cr) - BlurHash (https://github.com/woltapp/blurhash) implementation
 ⟡ crie (https://github.com/c910335/crie) - Compile-time Trie
 ⟡ CrOTP (https://github.com/philnash/crotp) - HOTP and TOTP implementation for two factor authentication
 ⟡ crystal-linked-list (https://github.com/abvdasker/crystal-linked-list) - Implementation of Linked List
 ⟡ crystaledge (https://github.com/unn4m3d/crystaledge) - A pure Vector Math library
 ⟡ crystalg (https://github.com/tobyapi/crystalg) - A Generic Algorithm Library
 ⟡ crystalline (https://github.com/jtomschroeder/crystalline) - A collection of containers and algorithms
 ⟡ csuuid (https://github.com/wyhaines/csuuid.cr) - A Chronologically Sortable UUID
 ⟡ edits.cr (https://github.com/tcrouch/edits.cr) - Collection of edit distance algorithms
 ⟡ fzy (https://github.com/hugopl/fzy) - A Crystal port of awesome Fzy project fuzzy finder algorithm
 ⟡ Goban (https://github.com/soya-daizu/goban) - A fast and efficient QR Code implementation
 ⟡ graphlb (https://github.com/mettuaditya/graphlb) - Collection of graph datastructure and algorithms
 ⟡ haversine (https://github.com/geocrystal/haversine) - An Implementation of the Haversine formula
 ⟡ HKDF (https://github.com/spider-gazelle/HKDF) - HMAC-based Extract-and-Expand Key Derivation Function rfc5869 (https://www.rfc-editor.org/rfc/rfc5869)
 ⟡ kd_tree (https://github.com/geocrystal/kd_tree) - An implementation of "K-Dimensional Tree" and "N-Nearest Neighbors"
 ⟡ ksuid.cr (https://github.com/Sija/ksuid.cr) - K-Sortable Globally Unique IDs
 ⟡ markov (https://github.com/mccallofthewild/markov) - Build Markov Chains and run Markov Processes
 ⟡ multiset.cr (https://github.com/tcrouch/multiset.cr) - Implementation of a multiset
 ⟡ named_information (https://github.com/spider-gazelle/named_information) - Naming Things with Hashes rfc6920 (https://datatracker.ietf.org/doc/html/rfc6920)
 ⟡ qr-code (https://github.com/spider-gazelle/qr-code) - QR Code generator
 ⟡ radix (https://github.com/luislavena/radix) - Radix Tree implementation
 ⟡ s2_cells (https://github.com/spider-gazelle/s2_cells) - S2 Geometry (https://s2geometry.io/devguide/s2cell_hierarchy.html) for spatial indexing
 ⟡ secure-remote-password (https://github.com/spider-gazelle/secure-remote-password) - SRP-6a protocol for authentication over an insecure network
 ⟡ SPAKE2+ (https://github.com/spider-gazelle/SPAKE2_plus) - Password Authenticated Key Exchange (PAKE) protocol, comparable to SRP-6a
 ⟡ splay_tree_map (https://github.com/wyhaines/splay_tree_map.cr) - Splay Tree implementation that conforms to the Hash ducktype
 ⟡ verhoeff (https://github.com/spider-gazelle/verhoeff) - Implementation of the Verhoeff checksum algorithm

Blockchain
 ⟡ Axentro (https://github.com/Axentro/Axentro) - A custom blockchain platform
 ⟡ Cocol (https://github.com/cocol-project/cocol) - A minimal blockchain testbed
 ⟡ secp256k1.cr (https://github.com/q9f/secp256k1.cr) - Elliptic curve used in the public-private-key cryptography

C bindings
 ⟡ augeas.cr (https://github.com/fernandes/augeas.cr) - Bindings for Augeas (https://augeas.net/)
 ⟡ clang.cr (https://github.com/crystal-lang/clang.cr) - Libclang bindings
 ⟡ crt.cr (https://github.com/maiha/crt.cr) - Bindings for libncursesw and crt
 ⟡ crystal-gsl (https://github.com/konovod/crystal-gsl) - Bindings for GNU Scientific Library (https://www.gnu.org/software/gsl/)
 ⟡ crystal-hunspell (https://github.com/mamantoha/crystal-hunspell) - Bindings for Hunspell (https://hunspell.github.io/)
 ⟡ duktape.cr (https://github.com/jessedoyle/duktape.cr) - Bindings for the Duktape (https://github.com/svaarala/duktape) javascript engine
 ⟡ fftw.cr (https://github.com/firejox/fftw.cr) - Bindings for FFTW (https://fftw.org/) library
 ⟡ gphoto2.cr (https://github.com/Sija/gphoto2.cr) - Bindings for the libgphoto2 (http://www.gphoto.org/) library
 ⟡ icu.cr (https://github.com/olbat/icu.cr) - Bindings for the ICU (http://site.icu-project.org/) library
 ⟡ libnotify.cr (https://github.com/splattael/libnotify.cr) - Bindings for Libnotify
 ⟡ nlopt.cr (https://github.com/konovod/nlopt.cr) - Bindings for NLOpt (https://nlopt.readthedocs.io/en/latest/)
 ⟡ pcap.cr (https://github.com/maiha/pcap.cr) - Bindings for libpcap
 ⟡ pledge.cr (https://github.com/chris-huxtable/pledge.cr) - Bindings for OpenBSD's pledge(2)
 ⟡ ssh2.cr (https://github.com/spider-gazelle/ssh2.cr) - Bindings for libssh2 library
 ⟡ syslog.cr (https://github.com/chris-huxtable/syslog.cr) - Bindings for syslog
 ⟡ v4l2.cr (https://github.com/spider-gazelle/v4l2.cr) - Bindings for Video4Linux2 (https://en.wikipedia.org/wiki/Video4Linux)
 ⟡ wasmer-crystal (https://github.com/naqvis/wasmer-crystal) - Bindings for the wasmer WebAssembly runtime
 ⟡ win32cr (https://github.com/mjblack/win32cr) - Bindings for Win32 API
 ⟡ x_do.cr (https://github.com/woodruffw/x_do.cr) - Bindings for libxdo (xdotool (https://github.com/jordansissel/xdotool))

Caching
 ⟡ crystal-memcached (https://github.com/comandeo/crystal-memcached) - Implementation of a memcached client

CLI Builders
 ⟡ admiral (https://github.com/jwaldrip/admiral.cr) - A robust DSL for writing command line interfaces
 ⟡ Athena Console (https://github.com/athena-framework/console) - Allows for the creation of CLI based commands
 ⟡ clicr (https://github.com/j8r/clicr) -  A simple declarative command line interface builder
 ⟡ clim (https://github.com/at-grandpa/clim) - Slim command line interface builder
 ⟡ Cling (https://github.com/devnote-dev/cling) - A modular, non-macro-based command line interface library
 ⟡ commander (https://github.com/mrrooijen/commander) - Command-line interface builder
 ⟡ Keimeno (https://github.com/robacarp/keimeno) -  A lightweight text user interface library in Crystal
 ⟡ OptionParser (https://crystal-lang.org/api/OptionParser.html) - command-line options processing (Crystal stdlib)
 ⟡ Phreak (https://github.com/shinzlet/phreak) - A highly flexible Crystal CLI builder in the style of OptionParser

CLI Utils
 ⟡ climate (https://github.com/Sija/climate.cr) - Tiny tool to make your CLI output 🌈  coloured
 ⟡ coin (https://github.com/caian-org/coin) - Command-line application that performs currency conversion via the Fixer API (https://fixer.io)
 ⟡ cride (https://github.com/j8r/cride) - A light CLI text editor/IDE
 ⟡ git-repository (https://github.com/place-labs/git-repository) - A git cli wrapper querying and cloning remote repositories with minimal data transfer
 ⟡ hetzner-k3s (https://github.com/vitobotta/hetzner-k3s) - A CLI tool to quickly create and manage Kubernetes clusters in Hetzner Cloud
 ⟡ lff (https://github.com/mkdika/lff-cr) - Simple and straightforward large files finder utility in command line
 ⟡ meet (https://github.com/ryanprior/meet) - Start a jitsi meeting quickly from the comfort of your command line
 ⟡ oq (https://github.com/Blacksmoke16/oq) - A performant, and portable jq wrapper to facilitate the consumption and output of formats other than JSON; using jq (https://github.com/stedolan/jq) filters to 
transform the data
 ⟡ progress_bar.cr (https://github.com/TPei/progress_bar.cr) - A simple and customizable progress bar
 ⟡ tablo (https://github.com/hutou/tablo) - A flexible terminal table generator
 ⟡ tallboy (https://github.com/epoch/tallboy) - Generate ASCII character tables with support for spanning cells over multiple columns

Code Analysis and Metrics
 ⟡ ameba (https://github.com/crystal-ameba/ameba) - A static code analysis tool
 ⟡ linguist.cr (https://github.com/microgit-com/linguist.cr) - Using multiple ways to find programming language used in files, based on Github's Linguist

Compression
 ⟡ Crystar (https://github.com/naqvis/crystar) - Readers and writers of Tar archive format
 ⟡ Gzip (https://crystal-lang.org/api/Compress/Gzip.html) - readers and writers of gzip format (Crystal stdlib)
 ⟡ polylines.cr (https://github.com/BuonOmo/polylines.cr) — compression of series of coordinates
 ⟡ snappy (https://github.com/naqvis/snappy) -  Snappy compression format reader/writer for Crystal
 ⟡ Zip (https://crystal-lang.org/api/Compress/Zip.html) - readers and writers of zip format (Crystal stdlib)
 ⟡ Zlib (https://crystal-lang.org/api/Compress/Zlib.html) - readers and writers of zlib format (Crystal stdlib)
 ⟡ zstd.cr (https://github.com/didactic-drunk/zstd.cr) - Bindings for Zstandard (https://github.com/facebook/zstd) compression library

Configuration
 ⟡ cr-dotenv (https://github.com/gdotdesign/cr-dotenv) - Loads .env file
 ⟡ Envy (https://github.com/grottopress/envy) - Load environment variables from YAML
 ⟡ envyable (https://github.com/philnash/envyable.cr) -  A simple YAML to ENV config loader
 ⟡ habitat (https://github.com/luckyframework/habitat) - Type safe configuration for your classes and modules
 ⟡ totem (https://github.com/icyleaf/totem) - Load and parse a configuration in JSON, YAML, dotenv formats

Converters
 ⟡ base62.cr (https://github.com/Sija/base62.cr) - Base62 encoder/decoder, well suited for url-shortening
 ⟡ crunits (https://github.com/spider-gazelle/crunits) - Tool for converting units of measure (miles to kilometers, celsius to fahrenheit etc)
 ⟡ money (https://github.com/crystal-money/money) - Handling money and currency conversion with ease (almost complete port of RubyMoney (https://github.com/RubyMoney/money))
 ⟡ sass.cr (https://github.com/straight-shoota/sass.cr) - Compile SASS/SCSS to CSS (libsass (https://github.com/sass/libsass/) binding)

Cryptography
 ⟡ cmac (https://github.com/spider-gazelle/cmac) - Crystal implementation of Cipher-based Message Authentication Code (CMAC)
 ⟡ ed25519 (https://github.com/spider-gazelle/ed25519) - the Ed25519 elliptic curve public-key signature system
described in RFC 8032 
 ⟡ monocypher.cr (https://github.com/konovod/monocypher.cr) - Crystal wrapper for the Monocypher crypto library
 ⟡ sodium.cr (https://github.com/didactic-drunk/sodium.cr) - Crystal wrapper for the libsodium crypto API

Data Formats
 ⟡ BinData (https://github.com/spider-gazelle/bindata) - Binary data parser helper with an ASN.1 (https://en.wikipedia.org/wiki/Abstract_Syntax_Notation_One) parser
 ⟡ config.cr (https://github.com/chris-huxtable/config.cr) - Easy to use configuration format parser
 ⟡ crinder (https://github.com/c910335/crinder) - Class based json renderer
 ⟡ Crystalizer (https://github.com/j8r/crystalizer) - (De)serialize any Crystal object; supporting JSON, YAML, and Byte formats out of the box
 ⟡ CSV (https://crystal-lang.org/api/CSV.html) - parsing and generating for comma-separated values (Crystal stdlib)
 ⟡ front_matter.cr (https://github.com/chris-huxtable/front_matter.cr) - Separates a files front matter from its content
 ⟡ geoip2.cr (https://github.com/delef/geoip2.cr) - GeoIP2 reader
 ⟡ HAR (https://github.com/NeuraLegion/har) - HAR (HTTP Archive) parser
 ⟡ INI (https://crystal-lang.org/api/INI.html) - INI file parser (Crystal stdlib)
 ⟡ JSON (https://crystal-lang.org/api/JSON.html) - parsing and generating JSON documents (Crystal stdlib)
 ⟡ json-schema (https://github.com/spider-gazelle/json-schema) - convert JSON serializable classes into a JSON Schema (https://json-schema.org/) representation
 ⟡ JSON::OnSteroids (https://github.com/anykeyh/json_on_steroids) - handle and mutate JSON document easily
 ⟡ maxminddb.cr (https://github.com/delef/maxminddb.cr) - MaxMindDB reader
 ⟡ toml.cr (https://github.com/crystal-community/toml.cr) - TOML parser
 ⟡ XML (https://crystal-lang.org/api/XML.html) - parsing and generating XML documents (Crystal stdlib)
 ⟡ YAML (https://crystal-lang.org/api/YAML.html) - parsing and generating YAML documents (Crystal stdlib)

Data Generators
 ⟡ faker (https://github.com/askn/faker) - A library for generating fake data
 ⟡ hashids.cr (https://github.com/splattael/hashids.cr) - A library to generate YouTube-like ids from one or many numbers
 ⟡ prime (https://github.com/wontruefree/prime) - A prime number generator

Database Drivers/Clients
 ⟡ couchdb.cr (https://github.com/TechMagister/couchdb.cr) - CouchDB client
 ⟡ cryomongo (https://github.com/elbywan/cryomongo) - MongoDB driver
 ⟡ crystal-db (https://github.com/crystal-lang/crystal-db) - Common db api
 ⟡ crystal-ldap (https://github.com/spider-gazelle/crystal-ldap) - LDAP client
 ⟡ crystal-mysql (https://github.com/crystal-lang/crystal-mysql) - MySQL connector for Crystal
 ⟡ crystal-pg (https://github.com/will/crystal-pg) - A Postgres driver
 ⟡ crystal-redis (https://github.com/stefanwille/crystal-redis) - Full featured Redis client
 ⟡ crystal-rethinkdb (https://github.com/kingsleyh/crystal-rethinkdb) - Driver for RethinkDB / RebirthDB
 ⟡ crystal-sqlite3 (https://github.com/crystal-lang/crystal-sqlite3) - SQLite3 bindings
 ⟡ leveldb (https://github.com/crystal-community/leveldb) - Crystal bindings for LevelDB
 ⟡ rocksdb.cr (https://github.com/maiha/rocksdb.cr) - RocksDB client
 ⟡ surrealdb.cr (https://github.com/yorci/surrealdb.cr) - Unoffical SurrealDB HTTP & Websocket Client

Database Tools
 ⟡ migrate (https://github.com/vladfaust/migrate.cr) - A simpler database migration tool with transactions

Debugging
⟡ backtracer.cr (https://github.com/Sija/backtracer.cr) - Shard aiming to assist with parsing backtraces into a structured form
⟡ debug.cr (https://github.com/Sija/debug.cr) - debug!(…) macro for pp-style debugging

Dependency Injection
 ⟡ Athena Dependency Injection (https://github.com/athena-framework/dependency-injection) - Robust dependency injection service container framework
 ⟡ Crystal-DI (https://github.com/funk-yourself/crystal-di) - Lightweight DI Container
 ⟡ HardWire (https://github.com/jerometwell/hardwire) - A compile-time non-intrusive dependency injection system
 ⟡ syringe (https://github.com/Bonemind/syringe) - A simple and basic dependency injection shard for crystal

Email
 ⟡ carbon (https://github.com/luckyframework/carbon) - Fun, testable, and adapter-based email library
 ⟡ crystal-email (https://github.com/arcage/crystal-email) - Simple e-mail sending library
 ⟡ CrystalEmail (https://git.sceptique.eu/Sceptique/CrystalEmail) - A RFC compliant Email validator
 ⟡ sendgrid.cr (https://github.com/dlanileonardo/sendgrid.cr) - Simple Sendgrid Client

Environment Management
 ⟡ asdf-crystal (https://github.com/marciogm/asdf-crystal) - Plugin for asdf version manager
 ⟡ crenv (https://github.com/crenv/crenv) - Crystal version manager
 ⟡ rcm.cr (https://github.com/maiha/rcm.cr) - Redis Cluster Manager

Examples and funny stuff
 ⟡ blackjack-cr (https://github.com/gdonald/blackjack-cr) - Console Blackjack
 ⟡ crystal-patterns (https://github.com/crystal-community/crystal-patterns) - Examples of GOF patters
 ⟡ crystalworld (https://github.com/vladfaust/crystalworld) - realworld.io (https://realworld.io) back-end API implementation
 ⟡ exercism-crystal (https://github.com/exercism/crystal) - Exercism exercises
 ⟡ try.cr (https://github.com/maiha/try.cr) - Try monad

Framework Components
 ⟡ Athena Event Dispatcher (https://github.com/athena-framework/event-dispatcher) - A Mediator and Observer pattern event library
 ⟡ Athena Negotiation (https://github.com/athena-framework/negotiation) - Framework agnostic content negotiation library
 ⟡ device_detector (https://github.com/creadone/device_detector) - Shard for detect device by user agent string
 ⟡ Exception Page (https://github.com/crystal-loot/exception_page) - An exceptional exception page for Crystal web libraries and frameworks
 ⟡ graphql (https://github.com/graphql-crystal/graphql) - Type-safe GraphQL (http://graphql.org) server implementation
 ⟡ graphql-crystal (https://github.com/ziprandom/graphql-crystal) - GraphQL (http://graphql.org) implementation
 ⟡ kemal-session (https://github.com/kemalcr/kemal-session) - Session handler for Kemal
 ⟡ mochi (https://github.com/awcrotwell/mochi) - Authentication shard inspired by Devise supporting: Authenticable, Confirmable, Invitable & more
 ⟡ motion.cr (https://github.com/awcrotwell/motion.cr) - Object oriented frontend library for Amber
 ⟡ multi-auth (https://github.com/msa7/multi_auth) - Standardized multi-provider OAuth2 authentication (inspired by omniauth)
 ⟡ praetorian (https://github.com/ilanusse/praetorian) - Minimalist authorization library inspired by Pundit
 ⟡ Shield (https://github.com/grottopress/shield) - Comprehensive security for Lucky framework
 ⟡ shrine.cr (https://github.com/jetrockets/shrine.cr) - File Attachment toolkit for Crystal applications. Heavily inspired by Shrine for Ruby
 ⟡ tourmaline (https://github.com/protoncr/tourmaline) - Telegram bot framework with an API loosely based on telegraf.js (https://telegraf.js.org/)

Game Development
 ⟡ CrSFML (https://github.com/oprypin/crsfml) - Bindings to SFML (https://www.sfml-dev.org/) multimedia/game library
 ⟡ crystal-chipmunk (https://github.com/oprypin/crystal-chipmunk) - Bindings to Chipmunk (http://chipmunk-physics.net/), a fast and lightweight 2D game physics library
 ⟡ crystal-imgui-sfml (https://github.com/oprypin/crystal-imgui-sfml) - Bindings to integrate Dear ImGui (https://github.com/ocornut/imgui) into an SFML (https://www.sfml-dev.org/) project
 ⟡ entitas.cr (https://github.com/spoved/entitas.cr) - A Entity Component System Framework for Crystal
 ⟡ MyECS (https://github.com/konovod/myecs) - A Sparse Entity Component System Framework for Crystal
 ⟡ Raylib-cr (https://github.com/sol-vin/raylib-cr) - Direct bindings to Raylib (https://raylib.com), which supports Linux, Windows, and Mac
 ⟡ SDL-Crystal-Bindings (https://github.com/Hadeweka/SDL-Crystal-Bindings) - Direct (unsafe) bindings to SDL2 (https://www.libsdl.org/), intended for writing own game libraries

GUI Development
 ⟡ crystal-imgui (https://github.com/oprypin/crystal-imgui) - Bindings to Dear ImGui (https://github.com/ocornut/imgui), an immediate-mode graphical UI library
 ⟡ GTK4.cr (https://github.com/hugopl/gtk4.cr) - Bindings for GTK4 (https://docs.gtk.org/gtk4/overview.html) with Crystalized API
 ⟡ Iu (https://github.com/grkek/iu) - UI framework based on the Fusion/libui.cr (https://github.com/Fusion/libui.cr) library, with custom elements and modified bindings from hedron-crystal/hedron 
(https://github.com/hedron-crystal/hedron)
 ⟡ Ultimate GTK4 Crystal Guide (https://ultimate-gtk4-crystal-guide.geopjr.dev/) - Learn how to create premium GTK4 apps in Crystal

HTML Builders
 ⟡ blueprint (https://github.com/gunbolt/blueprint) - Write reusable and testable HTML templates in plain Crystal
 ⟡ form_builder.cr (https://github.com/westonganger/form_builder.cr) - Dead simple HTML form builder for Crystal with built-in support for many popular UI libraries such as Bootstrap
 ⟡ to_html (https://github.com/sbsoftware/to_html.cr) - The fastest HTML builder engine for Crystal
 ⟡ Water (https://github.com/shootingfly/water) - A library for writing HTML in plain Crystal

HTML/XML Parsing
 ⟡ docx_cr_converter (https://github.com/aristotelesbr/docx_cr_converter) - parse DOCX Word
 ⟡ myhtml (https://github.com/kostya/myhtml) - Fast HTML5 Parser that includes CSS selectors

HTTP
 ⟡ Cable (https://github.com/cable-cr/cable) - An ActionCable "port" to Crystal, framework agnostic, 100% compatible with the ActionCable JS Client
 ⟡ cossack (https://github.com/crystal-community/cossack) - Simple flexible HTTP client
 ⟡ crest (https://github.com/mamantoha/crest) - Simple HTTP and REST client, inspired by the Ruby's RestClient gem
 ⟡ crul (https://github.com/porras/crul) - Command line HTTP client
 ⟡ digest-auth (https://github.com/spider-gazelle/digest-auth) - Digest authentication
 ⟡ halite (https://github.com/icyleaf/halite) - Crystal HTTP Requests with a chainable REST API, built-in sessions and loggers
 ⟡ http-multiserver.cr (https://github.com/vladfaust/http-multiserver.cr) - Mounting multiple servers via routes (a.k.a. URL mapping)
 ⟡ http-params-serializable (https://github.com/vladfaust/http-params-serializable) - HTTP params (de)serialization, applicable to URL queries and URL-encoded forms
 ⟡ http-protection (https://github.com/rogeriozambon/http-protection) - Protection against typical web attacks
 ⟡ http2 (https://github.com/ysbaddaden/http2) - HTTP/2 Protocol Implementation
 ⟡ HTTP::Client (https://crystal-lang.org/api/HTTP/Client.html) - HTTP client (Crystal stdlib)
 ⟡ HTTP::Server (https://crystal-lang.org/api/HTTP/Server.html) - HTTP server (Crystal stdlib)
 ⟡ HTTP::WebSocket (https://crystal-lang.org/api/HTTP/WebSocket.html) - HTTP WebSocket client (Crystal stdlib)
 ⟡ link-header (https://github.com/spider-gazelle/link-header) - HTTP Link Header Parser
 ⟡ ntlm (https://github.com/spider-gazelle/ntlm) - NTLM authentication
 ⟡ proxy-fetcher.cr (https://github.com/nbulaj/proxy-fetcher.cr) - Proxy lists fetching & validating library
 ⟡ sse.cr (https://github.com/y2k2mt/sse.cr) - Server-Sent Events (https://html.spec.whatwg.org/multipage/server-sent-events.html) client
Image processing
 ⟡ celestine (https://github.com/celestinecr/celestine) - Create SVG images using a DSL
 ⟡ ffmpeg (https://github.com/spider-gazelle/ffmpeg) - FFmpeg bindings that works with StumpyPNG to extract frames
 ⟡ Pluto (https://github.com/phenopolis/pluto) - A fast and convenient image processing library
 ⟡ stumpy_png (https://github.com/stumpycr/stumpy_png) - Read and write PNG images

Implementations/Compilers
 ⟡ charly (https://github.com/charly-lang) - Charly Programming Language
 ⟡ cltk (https://github.com/ziprandom/cltk) - A crystal port of the Ruby Language Toolkit
 ⟡ crisp (https://github.com/rhysd/Crisp) - Lisp dialect implemented with Crystal
 ⟡ LinCAS-lang (https://github.com/LinCAS-lang) - A programming language for scientific computation
 ⟡ mint-lang (https://github.com/mint-lang/mint) - A refreshing programming language for the front-end web
 ⟡ myst-lang (https://github.com/myst-lang/) - A practical, dynamic language designed to be written and understood as easily and efficiently as possible
 ⟡ novika (https://github.com/novika-lang/novika) - A free-form, moldable, interpreted programming language
 ⟡ runic-lang (https://github.com/runic-lang) - In-design toy language

Internationalization

 ⟡ crystal-i18n (https://github.com/crystal-i18n/i18n) - An internationalization library inspired by Ruby-I18n
 ⟡ i18n.cr (https://github.com/vladfaust/i18n.cr) - Internationalization shard
 ⟡ Lens (https://github.com/syeopite/lens) - A multiformat internationalization (i18n) shard for Crystal. Supports Gettext, Ruby YAML, etc.
 ⟡ Rosetta (https://github.com/wout/rosetta) - A blazing fast internationalization (i18n) library with compile-time key lookup supporting YAML and JSON formats

Logging and monitoring
 ⟡ crafana (https://github.com/spoved/crafana.cr) - A Grafana (https://grafana.com/) library to help autogenerate dashboards
 ⟡ fiber_metrics.cr (https://github.com/didactic-drunk/fiber_metrics.cr) - Track run time, wait time, or memory allocations per Fiber, method or block
 ⟡ Log (https://crystal-lang.org/api/Log.html) - logging utility (Crystal stdlib)
 ⟡ statsd.cr (https://github.com/miketheman/statsd.cr) - Statsd (https://github.com/etsy/statsd) client library

Machine Learning
 ⟡ ai4cr (https://github.com/drhuffman12/ai4cr) - Artificial Intelligence (based on https://github.com/SergioFierens/ai4r)
 ⟡ Cadmium (https://github.com/cadmiumcr/cadmium) - NLP library based heavily on natural (https://github.com/NaturalNode/natural)
 ⟡ crystal-fann (https://github.com/NeuraLegion/crystal-fann) - FANN (Fast Artifical Neural Network) binding
 ⟡ mxnet.cr (https://github.com/toddsundsted/mxnet.cr) - Bindings for MXNet (https://mxnet.incubator.apache.org/)
 ⟡ shainet (https://github.com/NeuraLegion/shainet) - SHAInet (Neural Network in pure crystal)

Markdown/Text Processors
 ⟡ cr-cmark-gfm (https://github.com/amauryt/cr-cmark-gfm) -  Crystal C bindings for cmark-gfm to work with Commonmark and Github Flavored Markdown
 ⟡ markd (https://github.com/icyleaf/markd) - Yet another markdown parser built for speed, Compliant to CommonMark specification

Misc
 ⟡ aasm.cr (https://github.com/veelenga/aasm.cr) - Easy to use finite state machine for Crystal classes
 ⟡ any_hash.cr (https://github.com/Sija/any_hash.cr) - Recursive Hash with better JSON::Any included
 ⟡ anyolite (https://github.com/Anyolite/anyolite) - Full mruby interpreter with simple bindings, allowing for easy scripting support in projects
 ⟡ burocracia.cr (https://github.com/vinibrsl/burocracia.cr) - burocracia.cr the dependecyless shard to validate, generate and format Brazilian burocracias such as CPF, CNPJ and CEP
 ⟡ callbacks (https://github.com/vladfaust/callbacks.cr) - Expressive callbacks module
 ⟡ circuit_breaker (https://github.com/TPei/circuit_breaker) - Implementation of the circuit breaker pattern
 ⟡ CrSignals (https://github.com/firejox/CrSignals) - Signals/slots notification library
 ⟡ crystal-binary_parser (https://github.com/DanSnow/crystal-binary_parser) - Binary parser
 ⟡ crystal-web-framework-stars (https://github.com/isaced/crystal-web-framework-stars) - Web frameworks for Crystal, most starred on Github
 ⟡ crz (https://github.com/dhruvrajvanshi/crz) - Functional programming library
 ⟡ defined (https://github.com/wyhaines/defined.cr) - macros for conditional compilation based on constant definitions, version requirements, or environment variable settings
 ⟡ emoji.cr (https://github.com/veelenga/emoji.cr) - Emoji library
 ⟡ gphoto2-web.cr (https://github.com/Sija/gphoto2-web.cr) - Web API for libgphoto2
 ⟡ immutable (https://github.com/lucaong/immutable) - Implementation of thread-safe, persistent, immutable collections
 ⟡ iterm2 (https://github.com/toddsundsted/iterm2) - Display images within the terminal using the ITerm2 Inline Images Protocol
 ⟡ monads (https://github.com/alex-lairan/monads) - Monad implementation
 ⟡ observable (https://github.com/TPei/observable) - Implementation of the observer pattern
 ⟡ pinger (https://github.com/spider-gazelle/pinger) - Ping IP addresses and DNS entries without requiring sudo
 ⟡ port_midi (https://github.com/jimm/crystal_port_midi) - Crystal C bindings for the PortMIDI cross-platform MIDI I/O library
 ⟡ retriable.cr (https://github.com/Sija/retriable.cr) - Simple DSL to retry failed code blocks
 ⟡ serf-handler.cr (https://github.com/wyhaines/serf-handler.cr) - Framework for building Serf handlers, with a suite of useful builtin capabilities
 ⟡ simple_retry (https://github.com/spider-gazelle/simple_retry) - Simple tool for retrying failed code blocks
 ⟡ sslscan.cr (https://github.com/NeuraLegion/sslscan.cr) - Crystal shard wrapping the rbsec/sslscan utility
 ⟡ version_tools (https://github.com/anicholson/crystal-version-tools) - Version-dependent behaviour, specified at compile-time
 ⟡ wafalyzer (https://github.com/NeuraLegion/wafalyzer) - Web Application Firewall (WAF) Detector - shard + cli
 ⟡ zaru_crystal (https://github.com/szTheory/zaru_crystal) - Filename sanitization

Network Protocols
 ⟡ amqp-client.cr (https://github.com/cloudamqp/amqp-client.cr) - AMQP 0-9.1, a messaging protocol, implemented by eg. RabbitMQ
 ⟡ connect-proxy (https://github.com/spider-gazelle/connect-proxy) - Connect method style of HTTP tunnelling / HTTP proxy
 ⟡ cr-xmpp (https://github.com/naqvis/cr-xmpp) - XMPP/Jabber Library
 ⟡ Crirc (https://github.com/Meoowww/Crirc) - IRC protocol implementation (Client, Server, Bots)
 ⟡ crystal-bacnet (https://github.com/spider-gazelle/crystal-bacnet) - BACnet protocol implementation with BACnet/IP client
 ⟡ crystal-dns (https://gitlab.com/jgillich/crystal-dns) - DNS protocol implementation and resolver
 ⟡ crystal-json-socket (https://github.com/foi/crystal-json-socket) - JSON-socket client & server implementation. Inspired by and compatible with node-json-socket 
(https://github.com/sebastianseilund/node-json-socket/) and ruby-json-socket (https://github.com/foi/ruby-json-socket)
 ⟡ crystal-mqtt (https://github.com/spider-gazelle/crystal-mqtt) - A MQTT client
 ⟡ crystal-snmp (https://github.com/spider-gazelle/crystal-snmp) - An SNMP implementation with version 1, 2c and 3 support
 ⟡ fast_irc.cr (https://github.com/RX14/fast_irc.cr) - Fast IRC parser/generator
 ⟡ jwt (https://github.com/crystal-community/jwt) - Implementation of JWT (JSON Web Token)
 ⟡ mDNS (https://github.com/spider-gazelle/mdns) - DNS Service Discovery and multicast DNS
 ⟡ mqtt-client.cr (https://github.com/84codes/mqtt-client.cr) - A fast and lightweight MQTT client
 ⟡ msgpack-crystal (https://github.com/crystal-community/msgpack-crystal) - MessagePack library
 ⟡ OAuth (https://crystal-lang.org/api/OAuth.html) - OAuth consumer (Crystal stdlib)
 ⟡ OAuth2 (https://crystal-lang.org/api/OAuth2.html) - OAuth2 client (Crystal stdlib)
 ⟡ OpenSSL (https://crystal-lang.org/api/OpenSSL.html) - bindings to libssl (Crystal stdlib)
 ⟡ simple_rpc (https://github.com/kostya/simple_rpc) - RPC Server and Client for Crystal. Implements msgpack-rpc protocol
 ⟡ stomp (https://github.com/spider-gazelle/stomp) - STOMP protocol
 ⟡ telnet.cr (https://github.com/spider-gazelle/telnet.cr) - Telnet protocol
 ⟡ transfer_more (https://git.sceptique.eu/Sceptique/transfer_more) - Clone of transfer.sh to uploads files

Networking
 ⟡ ipaddress.cr (https://github.com/Sija/ipaddress.cr) - Library to handle IPv4 and IPv6 addresses
 ⟡ mac-address (https://github.com/automatico/mac-address) - Library for working with MAC addresses

ORM/ODM Extensions
 ⟡ avram (https://github.com/luckyframework/avram) - A database wrapper for reading, writing, and migrating Postgres databases
 ⟡ clear (https://github.com/anykeyh/clear) - ORM specialized to PostgreSQL only but with advanced features
 ⟡ crecto (https://github.com/Crecto/crecto) - Database wrapper, based on Ecto
 ⟡ granite (https://github.com/amberframework/granite) - ORM for Postgres, Mysql, Sqlite
 ⟡ jennifer.cr (https://github.com/imdrasil/jennifer.cr) - Active Record pattern implementation with flexible query chainable builder and migration system
 ⟡ rethinkdb-orm (https://github.com/spider-gazelle/rethinkdb-orm) - ORM for RethinkDB / RebirthDB

Package Management
 ⟡ shards (https://github.com/crystal-lang/shards) - Dependency manager for the Crystal

Processes and Threads
 ⟡ await_async (https://github.com/anykeyh/await_async) - Add keywords await & async in Crystal Lang
 ⟡ concurrent.cr (https://github.com/didactic-drunk/concurrent.cr) - Simplified concurrency using streams/pipelines, waitgroups, semaphores, smores and more
 ⟡ neph (https://github.com/tbrand/neph) - A modern command line job processor that can execute jobs concurrently
 ⟡ promise (https://github.com/spider-gazelle/promise) - A Promise implementation with type inference
 ⟡ werk (https://github.com/marghidanu/werk) - Dead simple task runner with concurrent support, ideal for local CI

Project Generators
 ⟡ crystal_lib (https://github.com/crystal-lang/crystal_lib) - Automatic binding generator for native libraries
 ⟡ fez (https://github.com/jwoertink/fez) - A Kemal application generator
 ⟡ libgen (https://github.com/olbat/libgen) - Automatic bindings generator configured using JSON/YAML files

Queues and Messaging
 ⟡ crafka (https://github.com/BT-OpenSource/crafka) - Apache Kafka library utilizing librdkafka
 ⟡ mosquito (https://github.com/mosquito-cr/mosquito/) - Redis backed periodic and ad hoc job processing
 ⟡ NATS.io (https://github.com/nats-io/nats.cr) - NATS client
 ⟡ sidekiq.cr (https://github.com/mperham/sidekiq.cr) - Simple, efficient job processing

Routing
 ⟡ orion (https://github.com/obsidian/orion) - A minimal, rails-esque routing library
 ⟡ router.cr (https://github.com/tbrand/router.cr) - Minimum but powerful http router for HTTP::Server

Scheduling
 ⟡ crystime (https://gitlab.com/crystallabs/crystime) - Advanced time, calendar, schedule, and remind library
 ⟡ schedule.cr (https://github.com/hugoabonizio/schedule.cr) - Run periodic tasks
 ⟡ tasker (https://github.com/spider-gazelle/tasker) - A high precision scheduler including timezone aware cron jobs

Science and Data analysis
 ⟡ alea (https://github.com/nin93/alea) - Repeatable sampling, CDF and other utilities to work with probability distributions
 ⟡ ishi (https://github.com/toddsundsted/ishi) - Graph plotting package with a small API and sensible defaults powered by gnuplot
 ⟡ linalg (https://github.com/konovod/linalg) - Linear algebra library inspired by MATLAB and SciPy.linalg
 ⟡ num.cr (https://github.com/crystal-data/num.cr) - Numerical computing library supporting N-Dimensional data
 ⟡ predict.cr (https://github.com/RX14/predict.cr) - Satellite prediction library using the sgp4 model
 ⟡ quartz (https://github.com/RomainFranceschini/quartz) - Modeling and simulation framework

Search
 ⟡ hermes (https://github.com/imdrasil/hermes.cr) - Data Mapper pattern implementation for ElastiSearch

Serverless Computing
 ⟡ crystal_openfaas (https://github.com/TPei/crystal_openfaas/) - Template to enable crystal as first class citizens in OpenFaaS
 ⟡ secrets-env (https://github.com/spider-gazelle/secrets-env) - Extends ENV module to read values injected by docker / kubernetes secrets and other orchestration tools

System
 ⟡ baked_file_system (https://github.com/schovi/baked_file_system) - Virtual file system implementation
 ⟡ hardware (https://github.com/crystal-community/hardware) - Get CPU, Memory and Network informations of the running OS and its processes

Task management
 ⟡ cake (https://github.com/axvm/cake) - Production-ready Make-like utility tool
 ⟡ sam (https://github.com/imdrasil/sam.cr) - Another one Rake-like task manager with namespacing and arguments system

Template Engine
 ⟡ crinja (https://github.com/straight-shoota/crinja) - An implementation of the Jinja2 template engine (http://jinja.pocoo.org/)
 ⟡ crustache (https://github.com/MakeNowJust/crustache) - {{Mustache}} (https://mustache.github.io) for Crystal
 ⟡ ECR (Embedded Crystal) (https://crystal-lang.org/api/ECR.html) - compile time template language which uses plain crystal expressions (Crystal stdlib)
 ⟡ Jbuilder (https://github.com/shootingfly/jbuilder) - Generate JSON objects with a Builder-style DSL, inspired by jbuilder
 ⟡ Kilt (https://github.com/jeromegn/kilt) - Abstraction layer for template engines
 ⟡ Slang (https://github.com/jeromegn/slang) - Lightweight, terse, templating language inspired by Ruby's Slim
 ⟡ teeplate (https://github.com/mosop/teeplate) - A library for rendering multiple template files

Testing
 ⟡ Athena Spec (https://github.com/athena-framework/spec) - Common/helpful Spec (https://crystal-lang.org/api/Spec.html) compliant testing utilities
 ⟡ crotest (https://github.com/emancu/crotest) - A tiny and simple test framework
 ⟡ crytic (https://github.com/hanneskaeufler/crytic) - Mutation testing framework
 ⟡ hashr (https://github.com/crystal-china/hashr) - A tiny class makes test on JSON response easier
 ⟡ LuckyFlow (https://github.com/luckyframework/lucky_flow) - Automated browser tests similar to Capybara
 ⟡ mass-spec (https://github.com/c910335/mass-spec) - Web API testing library
 ⟡ microtest (https://github.com/Ragmaanir/microtest) - Small opinionated testing library focusing on power asserts
 ⟡ minitest.cr (https://github.com/ysbaddaden/minitest.cr) - Library for unit tests and assertions
 ⟡ mocks.cr (https://github.com/waterlink/mocks.cr) - Mocking library for Crystal
 ⟡ Spec (https://crystal-lang.org/api/Spec.html) - spec framework (Crystal stdlib)
 ⟡ spectator (https://gitlab.com/arctic-fox/spectator) - Feature rich spec framework that uses the modern expect syntax
 ⟡ timecop.cr (https://github.com/crystal-community/timecop.cr) - Library for mocking with Time.now. Inspired by the timecop ruby gem (https://github.com/travisjeffery/timecop)
 ⟡ vcr (https://github.com/spoved/vcr.cr) - A HTTP capture and replay implementation for crystal
 ⟡ webdriver_pump (https://github.com/bwilczek/webdriver_pump) - Page Object library. Inspired by Ruby's WatirPump (https://github.com/bwilczek/watir_pump)
 ⟡ webmock.cr (https://github.com/manastech/webmock.cr) - Library for stubbing HTTP::Client requests

Third-party APIs
 ⟡ amazonite (https://github.com/rjnienaber/amazonite) - An unofficial SDK supporting popular AWS APIs
 ⟡ aws-signer.cr (https://github.com/beanieboi/aws-signer.cr) - This library signs your HTTP requests using AWS v4
 ⟡ awscr-s3 (https://github.com/taylorfinnell/awscr-s3) - AWS S3 interface
 ⟡ awscr-signer (https://github.com/taylorfinnell/awscr-signer) - Sign HTTP::Request objects and generate presigned post forms
 ⟡ crystal-consul (https://github.com/rogerwelin/crystal-consul) - Consul API client
 ⟡ crystal-darksky (https://github.com/sb89/crystal-darksky) - Wrapper for the Dark Sky (https://darksky.net) API
 ⟡ crystal-swapi (https://github.com/sb89/crystal-swapi) - Star Wars API (SWAPI) wrapper
 ⟡ crystal_slack (https://github.com/manastech/crystal_slack) - A tool that parses Slack slash commands or send incoming web hooks
 ⟡ GDAX (https://github.com/mccallofthewild/gdax) - GDAX REST and WebSocket API Wrapper with request signing
 ⟡ gitlab.cr (https://github.com/icyleaf/gitlab.cr) - GitLab API wrapper
 ⟡ google (https://github.com/PlaceOS/google) - Google API wrapper
 ⟡ host_meta (https://github.com/toddsundsted/host_meta) - A Web Host Metadata (https://tools.ietf.org/html/rfc6415) client
 ⟡ kube-client.cr (https://github.com/spoved/kube-client.cr) - Kubernetes API Client
 ⟡ mixpanel-crystal (https://github.com/petoem/mixpanel-crystal) - A library for sending events to Mixpanel
 ⟡ mollie.cr (https://github.com/wout/mollie.cr) - Mollie (https://www.mollie.com/en/) Payments API wrapper (Creditcard, PayPal, Apple Pay, Sofort, Klarna, ...)
 ⟡ office365 (https://github.com/PlaceOS/office365) - Microsoft Graph API wrapper
 ⟡ pinboard.cr (https://github.com/oz/pinboard.cr) - Pinboard (https://pinboard.in) API
 ⟡ raven.cr (https://github.com/sija/raven.cr) - Raven is a client for Sentry (https://github.com/getsentry/sentry)
 ⟡ stripe.cr (https://github.com/confact/stripe.cr) - Stripe api wrapper
 ⟡ tmdb.cr (https://github.com/mmacia/tmdb.cr) - The Movie DB (TMDb) api wrapper
 ⟡ twitter-crystal (https://github.com/sferik/twitter-crystal) - A library to access the Twitter API
 ⟡ web_finger (https://github.com/toddsundsted/web_finger) - A WebFinger (https://tools.ietf.org/html/rfc7033) client
 ⟡ ynab.cr (https://github.com/jaredsmithse/ynab.cr) - A library to interact with your YNAB data

Validation
 ⟡ accord (https://github.com/neovintage/accord) - Shareable validation library for Crystal Objects
 ⟡ Athena Validator (https://github.com/athena-framework/validator) - Robust & flexible validation framework
 ⟡ validations (https://github.com/vladfaust/validations.cr) - Validations mixin
 ⟡ validator (https://github.com/Nicolab/crystal-validator) - Data check and validation

Web Frameworks
 ⟡ amber (https://github.com/amberframework/amber) - Open source efficient and cohesive web application framework
 ⟡ Athena (https://github.com/athena-framework/athena) - A web framework comprised of reusable, independent components
 ⟡ grip (https://github.com/grip-framework/grip) - The microframework for writing powerful web applications
 ⟡ kemal (https://github.com/kemalcr/kemal) - Lightning Fast, Super Simple web framework. Inspired by Sinatra
 ⟡ lucky (https://github.com/luckyframework/lucky) - Catch bugs early, forget about most performance issues, and spend more time on code instead of debugging and writing tests
 ⟡ marten (https://github.com/martenframework/marten) - A web framework that makes building web applications easy, productive, and fun
 ⟡ runcobo (https://github.com/runcobo/runcobo) - An api framework with simple, intuitive and consistent DSL, using jbuilder to render json
 ⟡ Shivneri (https://github.com/ujjwalguptaofficial/shivneri) - Component based MVC web framework for crystal targeting good code structures, modularity & performance
 ⟡ spider-gazelle (https://github.com/spider-gazelle/spider-gazelle) - A Rails esque web framework with a focus on speed and extensibility

                                                                                                     Community
 ⟡ Crystal Forum (https://forum.crystal-lang.org/)
 ⟡ Crystal newsletter (https://crystal-lang.org/#newsletter)
 ⟡ Gitter (https://gitter.im/crystal-lang/crystal)
 ⟡ IRC (ircs://irc.libera.chat:6697#crystal-lang) - #crystal-lang on Libera
 ⟡ Reddit (https://www.reddit.com/r/crystal_programming/)
 ⟡ Stackoverflow (https://stackoverflow.com/tags/crystal-lang/info)

Unofficial
 ⟡ Chinese-speaking Telegram Group (https://t.me/crystal_cn) - 来吧！TG 中文圈的朋友们！
 ⟡ Crystal Programming Discord Server (https://discord.gg/YS7YvQy) - Unofficial Discord server dedicated to the Crystal Programming Language
 ⟡ Portuguese-speaking Telegram Group (https://t.me/crystalbrasil) - Bem vindos ao Crystal Brasil!
 ⟡ Russian-speaking Telegram Group (https://t.me/crystal_ru) - Добро пожаловать, товарищ!

                                                                                                     Resources
 ⟡ Crystal for Rubyists (http://www.crystalforrubyists.com/) - Free book to bootstrap your Crystal journey
 ⟡ Crystal Shards for Ruby Gems (https://github.com/crystal-lang/crystal/wiki/Crystal-Shards-for-Ruby-Gems) - A list of Ruby Gems and their Crystal Shards equivalents
 ⟡ crystal-koans (https://github.com/ilmanzo/crystal-koans) - Learn Crystal by writing unit tests
 ⟡ crystal-lang.org (https://crystal-lang.org) - Official language site
 ⟡ devdocs.io (https://devdocs.io/crystal/) - API Documentation Browser with Crystal support
 ⟡ Programming Crystal (https://pragprog.com/book/crystal/programming-crystal) - PragProg book to start your Crystal journey

Official Documentation Translations
 ⟡ br.crystal-lang.org (http://br.crystal-lang.org/) - Brazilian
 ⟡ ja.crystal-lang.org (http://ja.crystal-lang.org/) - Japanese
 ⟡ kr.crystal-lang.org (https://kr.crystal-lang.org/) - Korean
 ⟡ ru.crystal-lang.org (http://ru.crystal-lang.org/) - Russian
 ⟡ tw.crystal-lang.org (http://tw.crystal-lang.org/) - Chinese Traditional

                                                                                                 Services and Apps
 ⟡ carc.in (https://carc.in/) - A web service that runs your code and displays the result
 ⟡ Crank (https://github.com/arktisklada/crank) - A Procfile-based application manager (like Foreman)
 ⟡ cry (https://github.com/elorest/cry) - Ability to execute crystal code in a fashion similar to Ruby's pry edit
 ⟡ Crystal ANN  (https://crystal-ann.com) - Announce new project, blog post, version update or any other Crystal work
 ⟡ DeBot (https://github.com/jhass/DeBot) - IRC bot written in Crystal
 ⟡ icr (https://github.com/crystal-community/icr) - Interactive console for Crystal (like IRB for Ruby)
 ⟡ Invidious (https://github.com/iv-org/invidious) - Invidious is an alternative front-end to YouTube
 ⟡ mpngin (https://github.com/thewalkingtoast/mpngin) - A URL shortener with simple stats
 ⟡ procodile (https://github.com/crystal-china/procodile_cr) - Run processes in the background (and foreground) on Mac & Linux from a Procfile (for production and/or development environments)
 ⟡ quicktype (https://quicktype.io/) - Generate models and serializers from JSON, JSON Schema, GraphQL, and TypeScript
 ⟡ shards.info (http://shards.info/) - Web service that lists all repositories on GitHub that have Crystal code in them. The sources are available on GitHub (https://github.com/mamantoha/shards-info)

                                                                                                       Tools
 ⟡ ast_helper (https://github.com/bcardiff/crystal-ast-helper) - Helper tool to debug parser and formatter
 ⟡ crystal-base (https://github.com/ruivieira/crystal-base) - CentOS base docker image for Crystal development
 ⟡ crystal-dash-docset (https://github.com/Sija/crystal-dash-docset) - Dash (https://kapeli.com/dash) docset generator
 ⟡ port_ruby_to_crystal (https://github.com/crystal-china/port_ruby_to_crystal) - A regex replace ruby script for port ruby code to crystal easier, reduce friction
 ⟡ public_suffix (https://github.com/toddsundsted/public_suffix) - A small library designed to make the Public Suffix List (https://publicsuffix.org/) easier to use

DevOps
 ⟡ ansible-crystal (https://github.com/CorbanR/ansible-crystal) - Ansible playbook for installing crystal
 ⟡ DPPM (https://github.com/DFabric/dppm) - An easy, universal way to install and manage applications as packages (mostly Linux)

Editor Plugins
 ⟡ Acme:
   ⟡ acmecrystal (https://github.com/ilanpillemer/acmecrystal) - Reformats crystal code in acme
 ⟡ Atom
   ⟡ crystal-tools (https://atom.io/packages/crystal-tools) - Enables built in tools in Crystal compiler
   ⟡ language-crystal-actual (https://atom.io/packages/language-crystal-actual) - Crystal language support in Atom
 ⟡ Emacs
   ⟡ crystal-mode (https://melpa.org/#/crystal-mode) - Crystal language support for Emacs (crystal-lang-tools/emacs-crystal-mode (https://github.com/crystal-lang-tools/emacs-crystal-mode))
 ⟡ Geany
   ⟡ geany-crystal (https://github.com/crystal-lang-tools/geany-crystal) - Crystal support for the Geany editor (https://www.geany.org/)
 ⟡ IntelliJ IDEA
   ⟡ intellij-crystal-lang (https://github.com/asedunov/intellij-crystal-lang) - Crystal support for the JetBrains IDEs
 ⟡ Lite-XL
   ⟡ lite-plugin-crystal (https://github.com/Tamnac/lite-plugin-crystal) - Crystal support for the Lite-XL (https://lite-xl.com/en/) editor
 ⟡ Spacemacs
   ⟡ crystal-spacemacs-layer (https://github.com/juanedi/crystal-spacemacs-layer) - Spacemacs contribution layer for Crystal
 ⟡ Sublime
   ⟡ sublime-crystal (https://github.com/crystal-lang-tools/sublime-crystal) - Crystal syntax highlighting for sublime Text
 ⟡ TextMate
   ⟡ Crystal.tmbundle (https://github.com/crystal-lang-tools/Crystal.tmbundle) - Crystal syntax highlighting, compile, format command, snippets
 ⟡ Vim
   ⟡ vim-crystal (https://github.com/vim-crystal/vim-crystal) - Vim filetype support for Crystal
   ⟡ vim-slang (https://github.com/elorest/vim-slang) - Vim filetype support for Slang Templating Engine
 ⟡ Visual Studio Code
   ⟡ vscode-crystal-lang (https://github.com/crystal-lang-tools/vscode-crystal-lang) - Formatter, linter and syntax highlighting for cr and ecr files

LSP Language Server Protocol Implementations
 ⟡ crystalline (https://github.com/elbywan/crystalline) - Crystalline is an implementation of the Language Server Protocol written in and for the Crystal Language
 ⟡ scry (https://github.com/crystal-lang-tools/scry) - Code analysis server for Crystal implementing the Language Server Protocol (https://microsoft.github.io/language-server-protocol/)

Shell plugins
 ⟡ crun (https://github.com/Val/crun) - Crystal Run : shebang wrapper for Crystal
 ⟡ crystal-zsh (https://github.com/veelenga/crystal-zsh) - .oh-my-zsh plugin