4 files changed, 4 insertions, 4 deletions
diff --git a/pkgs/applications/editors/elvis/default.nix b/pkgs/applications/editors/elvis/default.nix
index e1d2ad69b1d..0850dd0e7be 100644
--- a/pkgs/applications/editors/elvis/default.nix
+++ b/pkgs/applications/editors/elvis/default.nix
@@ -35,6 +35,6 @@ stdenv.mkDerivation rec {
   meta = {
     homepage = http://elvis.vi-editor.org/;
     description = "A vi clone for Unix and other operating systems";
-    license = "free";
+    license = stdenv.lib.licenses.free;
   };
 }
diff --git a/pkgs/applications/editors/emacs-modes/proofgeneral/4.3pre.nix b/pkgs/applications/editors/emacs-modes/proofgeneral/4.3pre.nix
index 32a036805ed..96d7619d387 100644
--- a/pkgs/applications/editors/emacs-modes/proofgeneral/4.3pre.nix
+++ b/pkgs/applications/editors/emacs-modes/proofgeneral/4.3pre.nix
@@ -47,7 +47,7 @@ stdenv.mkDerivation (rec {
       interactive theorem provers), based on the customizable text editor Emacs.
     '';
     homepage = http://proofgeneral.inf.ed.ac.uk;
-    license = "GPLv2+";
+    license = stdenv.lib.licenses.gpl2Plus;
     platforms = stdenv.lib.platforms.unix;  # arbitrary choice
   };
 })
diff --git a/pkgs/applications/editors/mg/default.nix b/pkgs/applications/editors/mg/default.nix
index 6901aed774b..45a527c7484 100644
--- a/pkgs/applications/editors/mg/default.nix
+++ b/pkgs/applications/editors/mg/default.nix
@@ -24,7 +24,7 @@ stdenv.mkDerivation rec {
   meta = {
     homepage = http://homepage.boetes.org/software/mg/;
     description = "Micro GNU/emacs, a portable version of the mg maintained by the OpenBSD team";
-    license = "public domain";
+    license = stdenv.lib.licenses.publicDomain;
     platforms = stdenv.lib.platforms.all;
   };
 }
diff --git a/pkgs/applications/editors/nvi/default.nix b/pkgs/applications/editors/nvi/default.nix
index 81e0dd35db9..ee9b775453c 100644
--- a/pkgs/applications/editors/nvi/default.nix
+++ b/pkgs/applications/editors/nvi/default.nix
@@ -49,6 +49,6 @@ stdenv.mkDerivation rec {
   meta = {
     homepage = http://www.bostic.com/vi/;
     description = "The Berkeley Vi Editor";
-    license = "free";
+    license = stdenv.lib.licenses.free;
   };
 }