diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc
index cd9a05bb2..d8d3e8bee 100644
--- a/src/libexpr/primops.cc
+++ b/src/libexpr/primops.cc
@@ -1528,7 +1528,9 @@ static void prim_pathExists(EvalState & state, const PosIdx pos, Value * * args,
     auto path = realisePath(state, pos, arg, { .checkForPureEval = false });
 
     /* SourcePath doesn't know about trailing slash. */
-    auto mustBeDir = arg.type() == nString && arg.str().ends_with("/");
+    auto mustBeDir = arg.type() == nString
+        && (arg.str().ends_with("/")
+            || arg.str().ends_with("/."));
 
     try {
         auto checked = state.checkSourcePath(path);
diff --git a/tests/lang/eval-okay-pathexists.nix b/tests/lang/eval-okay-pathexists.nix
index e1246e370..c5e7a62de 100644
--- a/tests/lang/eval-okay-pathexists.nix
+++ b/tests/lang/eval-okay-pathexists.nix
@@ -2,6 +2,27 @@ builtins.pathExists (./lib.nix)
 && builtins.pathExists (builtins.toPath ./lib.nix)
 && builtins.pathExists (builtins.toString ./lib.nix)
 && !builtins.pathExists (builtins.toString ./lib.nix + "/")
+&& !builtins.pathExists (builtins.toString ./lib.nix + "/.")
+# FIXME
+# && !builtins.pathExists (builtins.toString ./lib.nix + "/..")
+# && !builtins.pathExists (builtins.toString ./lib.nix + "/a/..")
+# && !builtins.pathExists (builtins.toString ./lib.nix + "/../lib.nix")
+&& !builtins.pathExists (builtins.toString ./lib.nix + "/./")
+&& !builtins.pathExists (builtins.toString ./lib.nix + "/./.")
+&& builtins.pathExists (builtins.toString ./.. + "/lang/lib.nix")
+&& !builtins.pathExists (builtins.toString ./.. + "lang/lib.nix")
+&& builtins.pathExists (builtins.toString ./. + "/../lang/lib.nix")
+&& builtins.pathExists (builtins.toString ./. + "/../lang/./lib.nix")
+&& builtins.pathExists (builtins.toString ./.)
+&& builtins.pathExists (builtins.toString ./. + "/")
+&& builtins.pathExists (builtins.toString ./. + "/../lang")
+&& builtins.pathExists (builtins.toString ./. + "/../lang/")
+&& builtins.pathExists (builtins.toString ./. + "/../lang/.")
+&& builtins.pathExists (builtins.toString ./. + "/../lang/./")
+&& builtins.pathExists (builtins.toString ./. + "/../lang//./")
+&& builtins.pathExists (builtins.toString ./. + "/../lang/..")
+&& builtins.pathExists (builtins.toString ./. + "/../lang/../")
+&& builtins.pathExists (builtins.toString ./. + "/../lang/..//")
 && builtins.pathExists (builtins.toPath (builtins.toString ./lib.nix))
 && !builtins.pathExists (builtins.toPath (builtins.toString ./bla.nix))
 && builtins.pathExists ./lib.nix