gnu: Add kmonad.

* gnu/packages/haskell-apps.scm (kmonad): New variable.

gnu/packages/haskell-apps.scm

@@ -12,6 +12,7 @@
 ;;; Copyright © 2019 Kyle Meyer <kyle@kyleam.com>
 ;;; Copyright © 2015 John Soo <jsoo1@asu.edu>
 ;;; Copyright © 2019 Efraim Flashner <efraim@flashner.co.il>
+;;; Copyright © 2019 Alex Griffin <a@ajgrf.com>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -498,6 +499,64 @@ (define-public hscolour
 and mIRC chat codes.")
     (license license:bsd-3)))
 
+(define-public kmonad
+  (package
+    (name "kmonad")
+    (version "0.2.0")
+    (source
+     (origin
+       (method git-fetch)
+       (uri (git-reference
+             (url "https://github.com/david-janssen/kmonad.git")
+             (commit "06d7b8c709efa695be35df9bde91275cbb2ba099")))
+       (file-name (git-file-name name version))
+       (sha256
+        (base32 "1rjr4h5yq63x3kad6yn4p8v26389sd9dgr5n2w73s1chafapzwwd"))))
+    (build-system haskell-build-system)
+    (arguments
+     `(#:phases
+       (modify-phases %standard-phases
+         (delete 'haddock)             ; Haddock fails to generate docs
+         (add-after 'install 'install-udev-rules
+           (lambda* (#:key outputs #:allow-other-keys)
+             (let* ((out (assoc-ref outputs "out"))
+                    (rules (string-append out "/lib/udev/rules.d")))
+               (mkdir-p rules)
+               (call-with-output-file (string-append rules "/70-kmonad.rules")
+                 (lambda (port)
+                   (display
+                    (string-append
+                     "KERNEL==\"uinput\", MODE=\"0660\", "
+                     "GROUP=\"input\", OPTIONS+=\"static_node=uinput\"\n")
+                    port)))
+               #t)))
+         (add-after 'install-udev-rules 'install-documentation
+           (lambda* (#:key outputs #:allow-other-keys)
+             (let* ((out (assoc-ref outputs "out"))
+                    (doc (string-append out "/share/doc/kmonad-" ,version)))
+               (install-file "README.md" doc)
+               (copy-recursively "doc" doc)
+               (copy-recursively "example" (string-append doc "/example"))
+               #t))))))
+    (inputs
+     `(("ghc-cereal" ,ghc-cereal)
+       ("ghc-exceptions" ,ghc-exceptions)
+       ("ghc-hashable" ,ghc-hashable)
+       ("ghc-lens" ,ghc-lens)
+       ("ghc-megaparsec" ,ghc-megaparsec-7)
+       ("ghc-optparse-applicative" ,ghc-optparse-applicative)
+       ("ghc-unagi-chan" ,ghc-unagi-chan)
+       ("ghc-unliftio" ,ghc-unliftio)
+       ("ghc-unordered-containers" ,ghc-unordered-containers)))
+    (home-page "https://github.com/david-janssen/kmonad")
+    (synopsis "Advanced keyboard manager")
+    (description "KMonad is a keyboard remapping utility that supports
+advanced functionality, such as custom keymap layers and modifiers, macros,
+and conditional mappings that send a different keycode when tapped or held.
+By operating at a lower level than most similar tools, it supports X11,
+Wayland, and Linux console environments alike.")
+    (license license:expat)))
+
 (define-public raincat
   (package
     (name "raincat")