diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -6,6 +6,10 @@
 and this project adheres to the
 [Haskell Package Versioning Policy](https://pvp.haskell.org/).
 
+## 0.1.9.1 - 2026-06-29
+
+* Add `extra-source-files` for test suite missing from `hi-file-parser-0.1.9.0`.
+
 ## 0.1.9.0 - 2026-06-28
 
 * Add support for GHC's support for module signatures (Backpack) from GHC 8.2.1.
diff --git a/hi-file-parser.cabal b/hi-file-parser.cabal
--- a/hi-file-parser.cabal
+++ b/hi-file-parser.cabal
@@ -5,7 +5,7 @@
 -- see: https://github.com/sol/hpack
 
 name:           hi-file-parser
-version:        0.1.9.0
+version:        0.1.9.1
 synopsis:       Parser for GHC's *.hi files
 description:    A parser for GHC's *.hi files. Extracts information about dependencies and
                 usage of files.
@@ -30,24 +30,54 @@
     test-files/iface/x64/ghc8022/X.hi
     test-files/iface/x64/ghc8044/Main.hi
     test-files/iface/x64/ghc8044/X.hi
+    test-files/iface/x64/ghc8044/signatures/Consumer.hi
+    test-files/iface/x64/ghc8044/signatures/LogHelper.hi
+    test-files/iface/x64/ghc8044/signatures/Main.hi
     test-files/iface/x64/ghc8065/Main.hi
     test-files/iface/x64/ghc8065/X.hi
+    test-files/iface/x64/ghc8065/signatures/Consumer.hi
+    test-files/iface/x64/ghc8065/signatures/LogHelper.hi
+    test-files/iface/x64/ghc8065/signatures/Main.hi
     test-files/iface/x64/ghc8084/Main.hi
     test-files/iface/x64/ghc8084/X.hi
+    test-files/iface/x64/ghc8084/signatures/Consumer.hi
+    test-files/iface/x64/ghc8084/signatures/LogHelper.hi
+    test-files/iface/x64/ghc8084/signatures/Main.hi
     test-files/iface/x64/ghc8107/Main.hi
     test-files/iface/x64/ghc8107/X.hi
+    test-files/iface/x64/ghc8107/signatures/Consumer.hi
+    test-files/iface/x64/ghc8107/signatures/LogHelper.hi
+    test-files/iface/x64/ghc8107/signatures/Main.hi
     test-files/iface/x64/ghc9002/Main.hi
     test-files/iface/x64/ghc9002/X.hi
+    test-files/iface/x64/ghc9002/signatures/Consumer.hi
+    test-files/iface/x64/ghc9002/signatures/LogHelper.hi
+    test-files/iface/x64/ghc9002/signatures/Main.hi
     test-files/iface/x64/ghc9028/Main.hi
     test-files/iface/x64/ghc9028/X.hi
+    test-files/iface/x64/ghc9028/signatures/Consumer.hi
+    test-files/iface/x64/ghc9028/signatures/LogHelper.hi
+    test-files/iface/x64/ghc9028/signatures/Main.hi
     test-files/iface/x64/ghc9044/Main.hi
     test-files/iface/x64/ghc9044/X.hi
+    test-files/iface/x64/ghc9044/signatures/Consumer.hi
+    test-files/iface/x64/ghc9044/signatures/LogHelper.hi
+    test-files/iface/x64/ghc9044/signatures/Main.hi
     test-files/iface/x64/ghc9048/Main.hi
     test-files/iface/x64/ghc9048/X.hi
+    test-files/iface/x64/ghc9048/signatures/Consumer.hi
+    test-files/iface/x64/ghc9048/signatures/LogHelper.hi
+    test-files/iface/x64/ghc9048/signatures/Main.hi
     test-files/iface/x64/ghc9067/Main.hi
     test-files/iface/x64/ghc9067/X.hi
+    test-files/iface/x64/ghc9067/signatures/Consumer.hi
+    test-files/iface/x64/ghc9067/signatures/LogHelper.hi
+    test-files/iface/x64/ghc9067/signatures/Main.hi
     test-files/iface/x64/ghc9084/Main.hi
     test-files/iface/x64/ghc9084/X.hi
+    test-files/iface/x64/ghc9084/signatures/Consumer.hi
+    test-files/iface/x64/ghc9084/signatures/LogHelper.hi
+    test-files/iface/x64/ghc9084/signatures/Main.hi
     test-files/iface/x64/ghc9103/Main.hi
     test-files/iface/x64/ghc9103/X.hi
     test-files/iface/x64/ghc9103/signatures/Consumer.hi
@@ -55,8 +85,14 @@
     test-files/iface/x64/ghc9103/signatures/Main.hi
     test-files/iface/x64/ghc9124/Main.hi
     test-files/iface/x64/ghc9124/X.hi
+    test-files/iface/x64/ghc9124/signatures/Consumer.hi
+    test-files/iface/x64/ghc9124/signatures/LogHelper.hi
+    test-files/iface/x64/ghc9124/signatures/Main.hi
     test-files/iface/x64/ghc9141/Main.hi
     test-files/iface/x64/ghc9141/X.hi
+    test-files/iface/x64/ghc9141/signatures/Consumer.hi
+    test-files/iface/x64/ghc9141/signatures/LogHelper.hi
+    test-files/iface/x64/ghc9141/signatures/Main.hi
 
 source-repository head
   type: git
diff --git a/test-files/iface/x64/ghc8044/signatures/Consumer.hi b/test-files/iface/x64/ghc8044/signatures/Consumer.hi
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