diff --git a/implementations/main.cpp b/implementations/main.cpp
index 642caef..6577884 100644
--- a/implementations/main.cpp
+++ b/implementations/main.cpp
@@ -1528,10 +1528,16 @@ std::string MapPath(std::uint32_t uid) {
 }
 
 fingerprintd::store::Map LoadMap(std::uint32_t uid) {
-    std::ifstream f(MapPath(uid));
-    if (!f) return {};
+    std::string path = MapPath(uid);
+    std::ifstream f(path);
+    if (!f) {
+        std::println("map {}: {}", path, ::strerror(errno));
+        return {};
+    }
     std::string text((std::istreambuf_iterator<char>(f)), std::istreambuf_iterator<char>());
-    return fingerprintd::store::Map::Decode(text);
+    auto m = fingerprintd::store::Map::Decode(text);
+    std::println("map {}: {} bytes, {} finger(s)", path, text.size(), m.Size());
+    return m;
 }
 
 void SaveMap(std::uint32_t uid, const fingerprintd::store::Map& m) {
@@ -1712,6 +1718,8 @@ void HandleDevice(GDBusMethodInvocation* inv, std::string_view method, GVariant*
         g_variant_get(params, "(&s)", &username);
         auto who = ResolveUser(username ? username : "", inv);
         if (!who) { ReturnError(inv, "Internal", "no such user"); return; }
+        std::println("ListEnrolledFingers('{}') -> {} uid {}", username ? username : "",
+                     who->first, who->second);
         auto m = LoadMap(who->second);
         if (m.Size() == 0) { ReturnError(inv, "NoEnrolledPrints", "no fingers enrolled"); return; }
         GVariantBuilder b;