diff --git a/ChangeLog.md b/ChangeLog.md
index c576dc16..bbd8d539 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -14,7 +14,6 @@ ChangeLog
  - [Get rid of dirty-pages list in MDBX_WRITEMAP mode](https://github.com/erthink/libmdbx/issues/193).
  - [Large/Overflow pages accounting for dirty-room](https://github.com/erthink/libmdbx/issues/192).
  - [Support for RAW devices](https://github.com/erthink/libmdbx/issues/124).
- - [Test framework issue](https://github.com/erthink/libmdbx/issues/127).
  - [Support MessagePack for Keys & Values](https://github.com/erthink/libmdbx/issues/115).
  - [Engage new terminology](https://github.com/erthink/libmdbx/issues/137).
  - Finalize C++ API (few typos and trivia bugs are still likely for now).
@@ -61,6 +60,7 @@ Fixes:
  - Fixed [using bad meta-pages if DB was partially/recoverable corrupted](https://github.com/erthink/libmdbx/issues/217).
  - Fixed extra `noexcept` for `buffer::&assign_reference()`.
  - Fixed `bootid` generation on Windows for case of change system' time.
+ - Fixed [test framework keygen-related issue](https://github.com/erthink/libmdbx/issues/127).
 
 
 ## v0.10.1 at 2021-06-01
diff --git a/test/keygen.cc b/test/keygen.cc
index 0cbd3299..566e2510 100644
--- a/test/keygen.cc
+++ b/test/keygen.cc
@@ -243,23 +243,25 @@ void maker::seek2end(serial_t &serial) const {
   serial = actor_params::serial_mask(mapping.width) - 1;
 }
 
-bool maker::increment(serial_t &serial, int delta) const {
+bool maker::increment(serial_t &serial, int64_t delta) const {
   if (serial > actor_params::serial_mask(mapping.width)) {
     log_extra("keygen-increment: %" PRIu64 " > %" PRIu64 ", overflow", serial,
               actor_params::serial_mask(mapping.width));
     return false;
   }
 
-  serial_t target = serial + (int64_t)delta;
+  serial_t target = serial + delta;
   if (target > actor_params::serial_mask(mapping.width) ||
       ((delta > 0) ? target < serial : target > serial)) {
-    log_extra("keygen-increment: %" PRIu64 "%-d => %" PRIu64 ", overflow",
+    log_extra("keygen-increment: %" PRIu64 "%-" PRId64 " => %" PRIu64
+              ", overflow",
               serial, delta, target);
     return false;
   }
 
-  log_extra("keygen-increment: %" PRIu64 "%-d => %" PRIu64 ", continue", serial,
-            delta, target);
+  log_extra("keygen-increment: %" PRIu64 "%-" PRId64 " => %" PRIu64
+            ", continue",
+            serial, delta, target);
   serial = target;
   return true;
 }
diff --git a/test/keygen.h b/test/keygen.h
index c7b758ab..2cb619aa 100644
--- a/test/keygen.h
+++ b/test/keygen.h
@@ -130,8 +130,8 @@ public:
   bool is_unordered() const;
   void seek2end(serial_t &serial) const;
 
-  bool increment(serial_t &serial, int delta) const;
-  bool increment_key_part(serial_t &serial, int delta,
+  bool increment(serial_t &serial, int64_t delta) const;
+  bool increment_key_part(serial_t &serial, int64_t delta,
                           bool reset_value_part = true) const {
     if (reset_value_part) {
       serial_t value_part_bits = ((serial_t(1) << mapping.split) - 1);
@@ -139,7 +139,7 @@ public:
       if (delta >= 0)
         serial &= ~value_part_bits;
     }
-    return increment(serial, delta << mapping.split);
+    return increment(serial, int64_t(uint64_t(delta) << mapping.split));
   }
 };