diff --git a/pkgs/applications/science/logic/sad/default.nix b/pkgs/applications/science/logic/sad/default.nix
index f9b82b5d733..f1066abf693 100644
--- a/pkgs/applications/science/logic/sad/default.nix
+++ b/pkgs/applications/science/logic/sad/default.nix
@@ -8,7 +8,7 @@ stdenv.mkDerivation {
   };
   buildInputs = [ haskell.compiler.ghc844 spass ];
   patches = [
-    ./patch
+    ./patch.patch
     # Since the LTS 12.0 update, <> is an operator in Prelude, colliding with
     # the <> operator with a different meaning defined by this package
     ./monoid.patch
diff --git a/pkgs/applications/science/logic/sad/patch b/pkgs/applications/science/logic/sad/patch.patch
similarity index 100%
rename from pkgs/applications/science/logic/sad/patch
rename to pkgs/applications/science/logic/sad/patch.patch
diff --git a/pkgs/development/libraries/physics/cernlib/default.nix b/pkgs/development/libraries/physics/cernlib/default.nix
index c6a9835d13b..8c4d688b697 100644
--- a/pkgs/development/libraries/physics/cernlib/default.nix
+++ b/pkgs/development/libraries/physics/cernlib/default.nix
@@ -16,7 +16,7 @@ stdenv.mkDerivation rec {
   nativeBuildInputs = [ gnumake imake makedepend ];
   sourceRoot = ".";
 
-  patches = [ ./patch ];
+  patches = [ ./patch.patch ];
 
   postPatch = ''
     substituteInPlace 2006/src/config/site.def \
diff --git a/pkgs/development/libraries/physics/cernlib/patch b/pkgs/development/libraries/physics/cernlib/patch.patch
similarity index 100%
rename from pkgs/development/libraries/physics/cernlib/patch
rename to pkgs/development/libraries/physics/cernlib/patch.patch
diff --git a/pkgs/tools/graphics/transfig/default.nix b/pkgs/tools/graphics/transfig/default.nix
index 960e7fd3ba3..9226809c5c5 100644
--- a/pkgs/tools/graphics/transfig/default.nix
+++ b/pkgs/tools/graphics/transfig/default.nix
@@ -11,11 +11,11 @@ stdenv.mkDerivation {
   buildInputs = [ zlib libjpeg libpng ];
 
   patches = [
-    ./patch-fig2dev-dev-Imakefile
-    ./patch-fig2dev-Imakefile
-    ./patch-transfig-Imakefile
-    ./patch-fig2dev-fig2dev.h
-    ./patch-fig2dev-dev-gensvg.c
+    ./patch-fig2dev-dev-Imakefile.patch
+    ./patch-fig2dev-Imakefile.patch
+    ./patch-transfig-Imakefile.patch
+    ./patch-fig2dev-fig2dev.h.patch
+    ./patch-fig2dev-dev-gensvg.c.patch
   ];
 
   patchPhase = ''
diff --git a/pkgs/tools/graphics/transfig/patch-fig2dev-Imakefile b/pkgs/tools/graphics/transfig/patch-fig2dev-Imakefile.patch
similarity index 100%
rename from pkgs/tools/graphics/transfig/patch-fig2dev-Imakefile
rename to pkgs/tools/graphics/transfig/patch-fig2dev-Imakefile.patch
diff --git a/pkgs/tools/graphics/transfig/patch-fig2dev-dev-Imakefile b/pkgs/tools/graphics/transfig/patch-fig2dev-dev-Imakefile.patch
similarity index 100%
rename from pkgs/tools/graphics/transfig/patch-fig2dev-dev-Imakefile
rename to pkgs/tools/graphics/transfig/patch-fig2dev-dev-Imakefile.patch
diff --git a/pkgs/tools/graphics/transfig/patch-fig2dev-dev-gensvg.c b/pkgs/tools/graphics/transfig/patch-fig2dev-dev-gensvg.c.patch
similarity index 100%
rename from pkgs/tools/graphics/transfig/patch-fig2dev-dev-gensvg.c
rename to pkgs/tools/graphics/transfig/patch-fig2dev-dev-gensvg.c.patch
diff --git a/pkgs/tools/graphics/transfig/patch-fig2dev-fig2dev.h b/pkgs/tools/graphics/transfig/patch-fig2dev-fig2dev.h.patch
similarity index 100%
rename from pkgs/tools/graphics/transfig/patch-fig2dev-fig2dev.h
rename to pkgs/tools/graphics/transfig/patch-fig2dev-fig2dev.h.patch
diff --git a/pkgs/tools/graphics/transfig/patch-transfig-Imakefile b/pkgs/tools/graphics/transfig/patch-transfig-Imakefile.patch
similarity index 100%
rename from pkgs/tools/graphics/transfig/patch-transfig-Imakefile
rename to pkgs/tools/graphics/transfig/patch-transfig-Imakefile.patch