diff --git a/pkgs/applications/editors/emacs/elisp-packages/elpa-packages.nix b/pkgs/applications/editors/emacs/elisp-packages/elpa-packages.nix
index d1f9dbd3a4a5..08d96268e7aa 100644
--- a/pkgs/applications/editors/emacs/elisp-packages/elpa-packages.nix
+++ b/pkgs/applications/editors/emacs/elisp-packages/elpa-packages.nix
@@ -106,7 +106,9 @@ self: let
         };
       });
 
-      jinx = super.jinx.overrideAttrs (old: {
+      jinx = super.jinx.overrideAttrs (old: let
+        libExt = pkgs.stdenv.targetPlatform.extensions.sharedLibrary;
+      in {
         dontUnpack = false;
 
         nativeBuildInputs = (old.nativeBuildInputs or [ ]) ++ [
@@ -117,12 +119,12 @@ self: let
 
         postBuild = ''
           NIX_CFLAGS_COMPILE="$($PKG_CONFIG --cflags enchant-2) $NIX_CFLAGS_COMPILE"
-          $CC -shared -o jinx-mod.so jinx-mod.c -lenchant-2
+          $CC -shared -o jinx-mod${libExt} jinx-mod.c -lenchant-2
         '';
 
         postInstall = (old.postInstall or "") + "\n" + ''
           outd=$out/share/emacs/site-lisp/elpa/jinx-*
-          install -m444 -t $outd jinx-mod.so
+          install -m444 -t $outd jinx-mod${libExt}
           rm $outd/jinx-mod.c $outd/emacs-module.h
         '';
 
diff --git a/pkgs/applications/editors/emacs/elisp-packages/melpa-packages.nix b/pkgs/applications/editors/emacs/elisp-packages/melpa-packages.nix
index 48234dc1189c..d91a3e7d8edb 100644
--- a/pkgs/applications/editors/emacs/elisp-packages/melpa-packages.nix
+++ b/pkgs/applications/editors/emacs/elisp-packages/melpa-packages.nix
@@ -314,7 +314,9 @@ let
 
         ivy-rtags = fix-rtags super.ivy-rtags;
 
-        jinx = super.jinx.overrideAttrs (old: {
+        jinx = super.jinx.overrideAttrs (old: let
+          libExt = pkgs.stdenv.targetPlatform.extensions.sharedLibrary;
+        in {
           nativeBuildInputs = (old.nativeBuildInputs or [ ]) ++ [
             pkgs.pkg-config
           ];
@@ -324,14 +326,14 @@ let
           postBuild = ''
             pushd working/jinx
             NIX_CFLAGS_COMPILE="$($PKG_CONFIG --cflags enchant-2) $NIX_CFLAGS_COMPILE"
-            $CC -shared -o jinx-mod.so jinx-mod.c -lenchant-2
+            $CC -shared -o jinx-mod${libExt} jinx-mod.c -lenchant-2
             popd
           '';
 
           postInstall = (old.postInstall or "") + "\n" + ''
             pushd source
             outd=$(echo $out/share/emacs/site-lisp/elpa/jinx-*)
-            install -m444 --target-directory=$outd jinx-mod.so
+            install -m444 --target-directory=$outd jinx-mod${libExt}
             rm $outd/jinx-mod.c $outd/emacs-module.h
             popd
           '';