diff --git a/lib/linguist/languages.yml b/lib/linguist/languages.yml
index 9bde77235a..8a755ed468 100644
--- a/lib/linguist/languages.yml
+++ b/lib/linguist/languages.yml
@@ -144,6 +144,12 @@ APL:
   color: "#5A8164"
   extensions:
   - ".apl"
+  - ".aplc"
+  - ".aplf"
+  - ".apli"
+  - ".apln"
+  - ".aplo"
+  - ".apls"
   - ".dyalog"
   interpreters:
   - apl