install

Additional install commands

macOS

Homebrewverified · 100%

brew install crystal-icr

local Homebrew formula metadata

Linux

Nixverified · 92%

nix profile install nixpkgs#icr

nixpkgs package indexes · pkgs/by-name/ic/icr/package.nix · source: api.github.com

overview

Package summary

Interactive console for Crystal programming language

Project links

Commands and aliases

icr

history

Project history and usage

ICR, short for Interactive Crystal, is a REPL-like console for the Crystal programming language. It exists because Crystal is normally compiled, so an interactive shell has to simulate the Ruby-style irb experience by generating and running Crystal programs behind the scenes.

Project history

The official GitHub repository was created in 2016 under the crystal-community organization. Its README presents the tool as an interactive console for Crystal and credits Potapov Sergey as creator and maintainer, with later community contributors adding support for newer Crystal versions, records, require flags, syntax highlighting, and maintenance.

Adoption history

ICR is a smaller companion package rather than part of Crystal's core distribution. The README documents source installation with make, use as a shard dependency, and an Arch AUR package; the supplied package metadata adds Homebrew and Nix packaging, showing that language-adjacent developer tools often get packaged separately from the compiler.

How it is used

ICR is used like irb for Crystal: each submitted instruction is accumulated into a generated Crystal program, executed, and presented as if only the new instruction ran. It supports requiring local files or shards from the command line and includes console commands such as paste, debug, quit, exit, and reset.

Why package nerds care

ICR is significant mostly as a packaging companion to Crystal. Its usefulness depends on matching the installed Crystal compiler, readline, and LLVM development files, so it illustrates why language ecosystems often need small auxiliary formulae beyond the main runtime.

Timeline

2016: The official GitHub repository was created.
2021: The repository's last pushed timestamp in the GitHub API indicates maintenance activity through the Crystal 0.x/early 1.x era.

Related projects

ICR is directly tied to Crystal and Shards. The README also points to inf-crystal.el as an editor integration for connecting Emacs to an ICR subprocess.

Sources

security posture

Risk level: yellow

generalized runtime or code generation signal.

Risk classifier

yellow risk · medium confidence · runtime

Why

generalized runtime or code generation signal

Signals

text:programming language

Install behavior

No Homebrew post-install hook is recorded in formula metadata.
Homebrew bottle metadata is available for 6 platform targets.
Installs with 7 runtime dependencies.

Recommended review

Before unattended agent use, check whether the tool reads plaintext credentials, writes remote state, publishes artifacts, or shells out to plugins.

executables

Installed executables

Command	Kind	Exposure	Note
`icr`	cli	global executable

freshness

Version and freshness

These signals separate page generation age, package-manager activity, and upstream release comparison. Version lag is warned only when an evidence URL and comparable versions are present.

page generated2026-07-08

manager version0.9.0

manager updated

local dataok

upstreamcurrent

latest detectedv0.9.0

https://github.com/crystal-community/icr

infoNo package-manager update timestamp was available.low confidence

install metadata

Package metadata

Package key	brew:crystal-icr
Version	0.9.0
Package manager	Homebrew
Package manager page	https://formulae.brew.sh/formula/crystal-icr
Homepage	https://github.com/crystal-community/icr
Repository	https://github.com/crystal-community/icr
Upstream docs	https://github.com/crystal-community/icr#readme
License	MIT
Source archive	https://github.com/crystal-community/icr/archive/refs/tags/v0.9.0.tar.gz
Dependencies	bdw-gc, crystal, libevent, libyaml, openssl@3, pcre2, readline
Bottle	available (on arm64_linux, arm64_sequoia, arm64_sonoma, arm64_tahoe, sonoma, x86_64_linux)
Homebrew post-install	not defined
Service	none declared

registry facts

Source database details

Source Database	Homebrew formula API
Tap	homebrew/core
Full Name	crystal-icr
Version Scheme	0
Revision	3
Bottle Stable Root URL	https://ghcr.io/v2/homebrew/core
Deprecated	no
Disabled	no
Keg Only	no
URL Keys	stable

source database matches

Other package-manager records

Matches are pulled from external package-manager indexes and kept separate from local Automic Vault package links.

Nix92%

icr

nix profile install nixpkgs#icr

installed executable or alias match
Matched by: Icr

nixpkgs package indexes · api.github.com · nixpkgs package indexes: pkgs/by-name/ic/icr/package.nix from https://api.github.com/repos/NixOS/nixpkgs/git/trees/master?recursive=1

package graph

Links come from deterministic package relationships, av.db category and tag curation, ecosystem matches, and package hub membership.

source trail

Generated from repository data

This page is generated by av-web from the private package SQLite artifact built by scripts/generate-pkg-sqlite.py.

Combined YAML source

View the package source record on GitHub.

combined/crystal-icr.yml

Used sources

Geiger risk classifier
Nucleus package database
av.db category and tag curation
cross-ecosystem install command graph
curated package history
external package-manager database matches
package relationship graph
package version freshness
package-page enrichment

Install crystal-icr with Homebrew, Nix