A ctags file generator for cabal project dependencies.

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LTS Haskell 6.35:
Stackage Nightly 2016-05-25:
Latest on Hackage:

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Apache-2.0 licensed by Alois Cochard
Maintained by

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This tool download and cache the source code of packages in your local hackage, it can then use this local cache to generate a tags file aggregating the sources of all the dependencies of a given cabal/stack project.

You basically do codex update in your project directory and you’ll get a file (codex.tags by default, or TAGS when using emacs format) that you can use in your favorite text editor.

By default the generated tags file will include tags of the current project as well, this functionality can be disabled in your ~/.codex file.


Codex is published on Hackage (and also mirrored on Stackage and NixOS).

cabal install codex

Note: You might have to install binary dependencies manually as cabal does not support them yet!


By default hasktags will be used, and need to be in the PATH, the tagger command can be fully customized in ~/.codex.

The configuration file is automatically generated with default values when running the tool for the first time.

codex [update] [cache clean] [set tagger [hasktags|ctags]] [set format [vim|emacs|sublime]]
  • update: Synchronize the tags file in the current project directory (use –force to discard tags file hash)
  • cache clean: Remove all tags file from the local hackage cache
  • set tagger [hasktags|ctags]: Update the ~/.codex configuration file for the given tagger
  • set format [vim|emacs|sublime]: Update the ~/.codex configuration file for the given format

Note: codex will browse the parent directory for cabal projects and use them as dependency over hackage when possible.


Put this in your .vimrc:

set tags=tags;/,codex.tags;/

IMPORTANT: You must use a version >= 7.4 (or you’ll get E431: Format error in tags file "codex.tags")




This CHANGELOG entry is incomplete, as it is reconstructed from the Git history since the previous release.

  • Fix codex update inside of cabal sandbox #74
  • Look for project packages in sub-directories #76
  • Improved error message if Hackage path not found #79
  • Use stack ls dependencies to avoid deprecation notice #81
  • Only use Stack when .stack-work is present #87
  • Support Cabal >= 2.2 #88
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