stylish-haskell

A simple Haskell code prettifier.

Runs as stylish-haskell|macOS, Linux, Windows|github.com

Open form in Otty otty.toml

Command form

ai-draft · 2 tasks · 6 fields

Prettify imports, pragmas and records in Haskell source files, printing the result or rewriting the files in place.

Opens the form; the finished command lands at your prompt, unrun

Run in Otty

otty gui stylish-haskell

Format Haskell filesExample values, fixed in this page — nothing here reaches a terminal

Basic

Files or directories*

any

Overwrite files in place*

--inplace

Recursive search

--recursive

Advanced

Config file

file

TasksEach one presets the form for one job

Format files in place

filesinplacerecursiveconfig

Preview formatted output

filesconfig

ParametersOnly these flags are editable in the form

Files or directories

Leave empty to read stdin. Directories need Recursive.
path · positional 0 · repeatable

Overwrite files in place

boolean

--inplace-i

Recursive search

boolean

--recursive-r

Config file

path

--config-c

Verbose

boolean

--verbose-v

Dump default config

Print the default configuration; redirect it to .stylish-haskell.yaml.
boolean

--defaults

SourcesEvery flag above is checked against these

src

-c,--config CONFIG Configuration file -r,--recursive Recursive file search -v,--verbose Run in verbose mode -d,--defaults Dump default config and exit -i,--inplace Overwrite the given files in place FILENAME Input file(s) (from src/Main.hs: long "config", short 'c'; long "recursive", short 'r…

manual2026-10-27

github.com

Before it fills your prompt, Otty checks the installed stylish-haskell against its version. A form that does not match your version is not offered.