diff --git a/lib/Fencer/Rules.hs b/lib/Fencer/Rules.hs
index c149167..430a498 100644
--- a/lib/Fencer/Rules.hs
+++ b/lib/Fencer/Rules.hs
@@ -15,7 +15,7 @@ import BasePrelude
 import qualified Data.HashMap.Strict as HM
 import Named ((:!), arg)
 import System.Directory (listDirectory, doesFileExist)
-import System.FilePath ((</>), takeExtension, takeFileName)
+import System.FilePath ((</>), takeFileName)
 import qualified Data.Yaml as Yaml
 
 import Fencer.Types
@@ -36,15 +36,11 @@ loadRulesFromDirectory
     files <-
         filterM doesFileExist . map (directory </>) =<<
         listDirectory directory
-    let ruleFiles =
-            (if ignoreDotFiles then filter (not . isDotFile) else id) $
-            filter isYaml files
-    mapM Yaml.decodeFileThrow ruleFiles
-    -- TODO: what does lyft/ratelimit do with unparseable files?
+    mapM Yaml.decodeFileThrow $
+        if ignoreDotFiles
+            then filter (not . isDotFile) files
+            else files
   where
-    isYaml :: FilePath -> Bool
-    isYaml file = takeExtension file `elem` [".yml", ".yaml"]
-
     isDotFile :: FilePath -> Bool
     isDotFile file = "." `isPrefixOf` takeFileName file
 
diff --git a/test/Fencer/Rules/Test.hs b/test/Fencer/Rules/Test.hs
index 446ac99..f97e52a 100644
--- a/test/Fencer/Rules/Test.hs
+++ b/test/Fencer/Rules/Test.hs
@@ -5,6 +5,7 @@
 -- | Tests for "Fencer.Rules".
 module Fencer.Rules.Test
   ( test_loadRulesYaml
+  , test_loadRulesNonYaml
   )
 where
 
@@ -35,6 +36,22 @@ test_loadRulesYaml =
         (sortOn domainDefinitionId [domain1, domain2])
         (sortOn domainDefinitionId definitions)
 
+-- | Test that 'loadRulesFromDirectory' loads rules from all files, not just
+-- YAML files.
+--
+-- This counterintuitive behavior matches the behavior of @lyft/ratelimit@.
+test_loadRulesNonYaml :: TestTree
+test_loadRulesNonYaml =
+  testCase "Rules are loaded from non-YAML files" $ do
+    Temp.withSystemTempDirectory "fencer-config" $ \tempDir -> do
+      TIO.writeFile (tempDir </> "config1.bin") domain1Text
+      TIO.writeFile (tempDir </> "config2") domain2Text
+      definitions <-
+        loadRulesFromDirectory (#directory tempDir) (#ignoreDotFiles True)
+      assertEqual "unexpected definitions"
+        (sortOn domainDefinitionId [domain1, domain2])
+        (sortOn domainDefinitionId definitions)
+
 ----------------------------------------------------------------------------
 -- Sample definitions
 ----------------------------------------------------------------------------