diff --git a/flake.nix b/flake.nix
index bb11b62d8..e4a513a7a 100644
--- a/flake.nix
+++ b/flake.nix
@@ -369,6 +369,7 @@
               "nix-expr-tests" = { };
 
               "nix-flake" = { };
+              "nix-flake-c" = { };
               "nix-flake-tests" = { };
 
               "nix-main" = { };
diff --git a/src/libflake-c/meson.build b/src/libflake-c/meson.build
index fd3cdd01b..435035b86 100644
--- a/src/libflake-c/meson.build
+++ b/src/libflake-c/meson.build
@@ -37,6 +37,7 @@ include_dirs = [include_directories('.')]
 
 headers = files(
   'nix_api_flake.h',
+  'nix_api_flake_internal.hh',
 )
 
 # TODO move this header to libexpr, maybe don't use it in tests?