Syntax checkers for buffer Main.hs in haskell-mode:

  intero
    - may enable: yes
    - predicate:  t

  haskell-stack-ghc
    - may enable: yes
    - executable: Found at /home/fredefox/.local/bin/stack

  haskell-ghc
    - may enable: yes
    - executable: Found at /home/fredefox/.stack/programs/x86_64-linux/ghc-nopie-8.0.2/bin/ghc

  haskell-hlint
    - may enable:         yes
    - executable:         Found at /home/fredefox/.local/bin/hlint
    - configuration file: Not found

The following checker is explicitly selected for this buffer:

  intero
    - major mode: `haskell-mode' supported
    - may enable: yes
    - predicate:  t

Flycheck Mode is enabled. Use M-m u C-c ! x to enable disabled checkers.

--------------------

Flycheck version: 32snapshot (package: 20171126.1339)
Emacs version:    25.2.2
System:           x86_64-pc-linux-gnu
Window system:    x