diff --git a/pkgs/tools/filesystems/encfs/default.nix b/pkgs/tools/filesystems/encfs/default.nix
index dcc80c0acca7..7d43131ea403 100644
--- a/pkgs/tools/filesystems/encfs/default.nix
+++ b/pkgs/tools/filesystems/encfs/default.nix
@@ -10,6 +10,7 @@
   fuse,
   openssl,
   tinyxml2,
+  gtest,
 }:
 
 stdenv.mkDerivation rec {
@@ -36,6 +37,7 @@ stdenv.mkDerivation rec {
     fuse
     openssl
     tinyxml2
+    gtest
   ];
   nativeBuildInputs = [
     cmake
@@ -49,6 +51,12 @@ stdenv.mkDerivation rec {
     "-DUSE_INTERNAL_TINYXML=OFF"
     "-DBUILD_SHARED_LIBS=ON"
     "-DINSTALL_LIBENCFS=ON"
+
+    # Fix the build with CMake 4.
+    #
+    # Upstream is deprecated, so it won’t be fixed there. We should
+    # probably phase this package out.
+    "-DCMAKE_POLICY_VERSION_MINIMUM=3.10"
   ];
 
   meta = with lib; {