diff --git a/modules/outputs.nix b/modules/outputs.nix
index 98edad5..f244657 100644
--- a/modules/outputs.nix
+++ b/modules/outputs.nix
@@ -69,13 +69,22 @@ in
           out what's in the image, which is nice if it's unexpectedly huge
         '';
       };
-      rootfsFiles = mkOption {
+      rootdir = mkOption {
         type = types.package;
         internal = true;
         description = ''
           directory of files to package into root filesystem
         '';
       };
+      bootablerootdir = mkOption {
+        type = types.package;
+        internal = true;
+        description = ''
+          directory of files to package into root filesystem, including
+          a kernel and appropriate associated gubbins for the
+          selected bootloader
+        '';
+      };
       rootfs = mkOption {
         type = types.package;
         internal = true;
@@ -108,7 +117,7 @@ in
         inherit kernel;
         inherit dtb;
       };
-      rootfsFiles =
+      rootdir =
         let
           inherit (pkgs.pkgsBuildBuild) runCommand;
         in runCommand "mktree" { } ''
@@ -120,6 +129,15 @@ in
             (cd $out && cp -a $path .$path)
           done
         '';
+      bootablerootdir =
+        let inherit (pkgs.pkgsBuildBuild) runCommand;
+        in runCommand "add-slash-boot" { } ''
+          cp -a ${o.rootdir} $out
+          ${if config.boot.loader.extlinux.enable
+            then "(cd $out && chmod -R +w . && rmdir boot && cp -a ${o.extlinux} boot)"
+            else ""
+           }
+         '';
       manifest = writeText "manifest.json" (builtins.toJSON config.filesystem.contents);
     };
   };
diff --git a/modules/outputs/ext4fs.nix b/modules/outputs/ext4fs.nix
index db3fd0f..3ba9a07 100644
--- a/modules/outputs/ext4fs.nix
+++ b/modules/outputs/ext4fs.nix
@@ -28,16 +28,12 @@ in
         in runCommand "mkfs.ext4" {
           depsBuildBuild = [ e2fsprogs ];
         } ''
-          cp -a ${o.rootfsFiles} tmp
-          ${if config.boot.loader.extlinux.enable
-            then "(cd tmp && chmod -R +w . && rmdir boot && cp -a ${o.extlinux} boot)"
-            else ""
-          }
-          size=$(du -s --apparent-size --block-size 1024 tmp |cut -f1)
+          tree=${o.bootablerootdir}
+          size=$(du -s --apparent-size --block-size 1024 $tree |cut -f1)
           # add 25% for filesystem overhead
           size=$(( 5 * $size / 4))
           dd if=/dev/zero of=$out bs=1024 count=$size
-          mke2fs -t ext4 -j -d tmp $out
+          mke2fs -t ext4 -j -d $tree $out
         '';
     };
   };
diff --git a/modules/outputs/jffs2.nix b/modules/outputs/jffs2.nix
index a1b9c2a..647aab9 100644
--- a/modules/outputs/jffs2.nix
+++ b/modules/outputs/jffs2.nix
@@ -34,12 +34,8 @@ in
         in runCommand "make-jffs2" {
           depsBuildBuild = [ mtdutils ];
         } ''
-          cp -a ${o.rootfsFiles} tmp
-          ${if config.boot.loader.extlinux.enable
-            then "(cd tmp && ln -s ${o.extlinux} boot)"
-            else ""
-          }
-          (cd tmp && mkfs.jffs2 --compression-mode=size ${endian} -e ${toString config.hardware.flash.eraseBlockSize} --enable-compressor=lzo --pad --root . --output $out --squash --faketime )
+          tree=${o.bootablerootdir}
+          (cd $tree && mkfs.jffs2 --compression-mode=size ${endian} -e ${toString config.hardware.flash.eraseBlockSize} --enable-compressor=lzo --pad --root . --output $out --squash --faketime )
         '';
     };
   };
diff --git a/modules/outputs/ubifs.nix b/modules/outputs/ubifs.nix
index 4f93cf0..26c8ad3 100644
--- a/modules/outputs/ubifs.nix
+++ b/modules/outputs/ubifs.nix
@@ -36,12 +36,8 @@ in
           depsBuildBuild = [ mtdutils ];
         } ''
           mkdir tmp
-          cp -a ${o.rootfsFiles} tmp
-          ${if config.boot.loader.extlinux.enable
-            then "(cd tmp && ln -s ${o.extlinux} boot)"
-            else ""
-           }
-          mkfs.ubifs -x favor_lzo -c ${cfg.maxLEBcount} -m ${cfg.minIOSize} -e ${cfg.eraseBlockSize}  -y -r tmp --output $out  --squash-uids -o $out
+          tree=${o.bootablerootdir}
+          mkfs.ubifs -x favor_lzo -c ${cfg.maxLEBcount} -m ${cfg.minIOSize} -e ${cfg.eraseBlockSize}  -y -r $tree --output $out  --squash-uids -o $out
         '';
     };
   };