This may help :-) (flycheck-define-checker proselint "A linter for prose." :command ("proselint" source-inplace) :error-patterns ((wa

This may help :-) (flycheck-define-checker proselint "A linter for prose." :command ("proselint" source-inplace) :error-patterns ((warning line-start (file-name) ":" line ":" column ": " (id (one-or-more (not (any " ")))) (message (one-or-more not-newline) (zero-or-more "\n" (any " ") (one-or-more not-newline))) line-end)) :modes (text-mode markdown-mode gfm-mode org-mode)) (More details in my config at https://jamiecollinson.com/blog/my-emacs-config/#syntax-checking https://jamiecollinson.com/blog/my-emacs-config/#syntax-chec...)