install

Additional install commands

macOS

Homebrewverified · 100%

brew install fernflower

local Homebrew formula metadata

Linux

Fedora dnfverified · 92%

sudo dnf install fernflower

Fedora Rawhide package metadata · fernflower · source: dl.fedoraproject.org

overview

Package summary

Advanced decompiler for Java bytecode

Project links

Commands and aliases

fernflower

history

Project history and usage

Fernflower is JetBrains' Java bytecode decompiler engine. Its README describes it as an analytical Java decompiler, bundled in IntelliJ IDEA for viewing Java source while debugging or navigating class files, and usable as a standalone command-line JAR.

Project history

Fernflower predates its current GitHub repository history: the README credits the original development to Stiver and says JetBrains has maintained it since 2014. The GitHub repository itself was created in October 2014 and points to the IntelliJ Community repository as the release location.

The project became part of the wider IntelliJ Java tooling stack rather than a standalone decompiler-only product. Its repository README tells contributors to send patches through the IntelliJ Community project, and its issue tracker route is the IntelliJ IDEA `Java. Decompiler. Engine` subsystem.

Adoption history

Fernflower's main adoption channel is IntelliJ IDEA, where it is bundled for class-file navigation and debugging. Package-manager adoption gives command-line users a standalone `fernflower` executable or wrapper without needing to extract the engine from an IDE installation.

The README also notes that patches from ForgeFlower were merged and that a long-running mirror by Andrew McRae existed, which reflects Fernflower's role in the broader Java reverse-engineering and Minecraft-modding adjacent decompiler ecosystem.

How it is used

Standalone usage runs `java -jar fernflower.jar` with options, one or more class/JAR/ZIP sources, and an output destination. The documented options cover generic signatures, inner classes, synthetic members, lambda handling, identifier renaming, logging, line endings, indentation, and other decompiler behavior.

Inside IntelliJ IDEA, Fernflower is used implicitly when a developer opens or debugs against compiled Java classes without source attached. That dual IDE-and-CLI role is why it is useful both to Java developers and to package users who want scriptable decompilation.

Why package nerds care

Fernflower matters in package culture because it packages a decompiler engine from a large IDE ecosystem into a small command-line tool. It also sits at an interesting boundary: official releases are tied to JetBrains' IntelliJ infrastructure, while downstream package managers expose it as a normal CLI.

For Java tooling maintainers, it is a notable example of an IDE component with standalone utility, Apache-licensed source, and ongoing relevance as Java bytecode features evolve.

Timeline

2014: JetBrains begins maintaining Fernflower and the public GitHub repository is created.
2014 onward: Fernflower is maintained as part of the IntelliJ Java decompiler engine.
2026: GitHub repository metadata shows continuing updates.

Related projects

Fernflower is related to IntelliJ IDEA, the IntelliJ Community repository, ForgeFlower, and the wider family of Java bytecode decompilers used by developers and reverse engineers.

Sources

security posture

No protected-tool coverage found yet

No matching local secret-handling manifest was found for fernflower. Nucleus package metadata is still published here so future coverage has a stable package URL.

Install behavior

No Homebrew post-install hook is recorded in formula metadata.
Homebrew bottle metadata is available for 1 platform targets.
Installs with 1 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
`fernflower`	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 version261.26222.65

manager updated2026-07-02

local dataok

upstreamnot checked

latest detectednot detected

https://github.com/JetBrains/fernflower

infoNo cached GitHub release or tag data was available.https://github.com/JetBrains/fernflowernone confidence

install metadata

Package metadata

Package key	brew:fernflower
Version	261.26222.65
Package manager	Homebrew
Package manager page	https://formulae.brew.sh/formula/fernflower
Homepage	https://github.com/JetBrains/fernflower
Repository	https://github.com/JetBrains/fernflower
Upstream docs	https://github.com/JetBrains/fernflower#readme
License	Apache-2.0
Source archive	https://www.jetbrains.com/intellij-repository/releases/com/jetbrains/intellij/java/java-decompiler-engine/261.26222.65/java-decompiler-engine-261.26222.65.jar
Last updated	2026-07-02T16:39:41Z
Pulse	updated
Dependencies	openjdk
Bottle	available (on all)
Homebrew post-install	not defined
Service	none declared

registry facts

Source database details

Source Database	Homebrew formula API
Tap	homebrew/core
Full Name	fernflower
Version Scheme	0
Revision	0
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.

dnf95%

fernflower 211.7442.40-17.fc44

JIdea's java decompiler

https://github.com/JetBrains/intellij-community/tree/master/plugins/java-decompiler/engine

sudo dnf install fernflower

License: Apache-2.0
Category: Unspecified
Architecture: noarch
Source Package: fernflower
2 dependencies
2 provides
normalized package name match
Matched by: Fernflower

Fedora Rawhide package metadata · dl.fedoraproject.org · Fedora Rawhide package metadata: fernflower from https://dl.fedoraproject.org/pub/fedora/linux/development/rawhide/Everything/x86_64/os/repodata/e5ca8ce900cd68f5419e1c39ae517343100b306336cbaeb70a3c153121d95094-primary.xml.zst

dnf95%

fernflower-javadoc 211.7442.40-17.fc44

fernflower API documentation

https://github.com/JetBrains/intellij-community/tree/master/plugins/java-decompiler/engine

sudo dnf install fernflower-javadoc

License: Apache-2.0
Category: Unspecified
Architecture: noarch
Source Package: fernflower
1 dependencies
2 provides
normalized package name match
Matched by: Fernflower

Fedora Rawhide package metadata · dl.fedoraproject.org · Fedora Rawhide package metadata: fernflower-javadoc from https://dl.fedoraproject.org/pub/fedora/linux/development/rawhide/Everything/x86_64/os/repodata/e5ca8ce900cd68f5419e1c39ae517343100b306336cbaeb70a3c153121d95094-primary.xml.zst

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/fernflower.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 fernflower with Homebrew, dnf