diff --git a/src/cryogen_core/io.clj b/src/cryogen_core/io.clj
index 6eea7bc..15c7dc2 100644
--- a/src/cryogen_core/io.clj
+++ b/src/cryogen_core/io.clj
@@ -47,7 +47,7 @@
 
 (defn copy-dir [src target ignored-files]
   (fs/mkdirs target)
-  (let [^java.io.FileFilter filename-filter (apply reject-re-filter ignored-files)
+  (let [^java.io.FilenameFilter filename-filter (apply reject-re-filter ignored-files)
         files (.listFiles (io/file src) filename-filter)]
     (doseq [^java.io.File f files]
       (let [out (io/file target (.getName f))]
diff --git a/src/cryogen_core/sass.clj b/src/cryogen_core/sass.clj
index 6f767e0..6e4d8c8 100644
--- a/src/cryogen_core/sass.clj
+++ b/src/cryogen_core/sass.clj
@@ -23,7 +23,7 @@
   "Given a Diretory, gets files, Filtered to those having scss or sass
   extention. Ignores files matching any ignored regexps."
   [base-dir dir ignored-files]
-  (let [^java.io.FileFilter filename-filter (match-re-filter #"(?i:s[ca]ss$)")]
+  (let [^java.io.FilenameFilter filename-filter (match-re-filter #"(?i:s[ca]ss$)")]
     (->> (.listFiles (io/file base-dir dir) filename-filter)
          (filter #(not (.isDirectory ^java.io.File %)))
          (filter (ignore ignored-files))