diff --git a/README.md b/README.md
index bf02cbb..c2025fd 100644
--- a/README.md
+++ b/README.md
@@ -40,9 +40,9 @@ editable-build requirements for Python3.10-3.12. Every registry package is fixed
 version. The `dev` extra names Python3.10's conditional compatibility dependencies explicitly so
 a lock compiled on Python3.12 remains complete for the whole matrix. The internal package is also
 fixed by its released annotated tag:
-`quant-data-kit@v0.7.4`, from `https://github.com/PureSaber/quant-data-kit.git`, resolving to
-commit `ecb04bd5834aeefdf79226c15cba484337785f90` through annotated tag object
-`49976e938c0b00c0a083b0c4175cc6a879a3f988`.
+`quant-data-kit@v0.8.1`, from `https://github.com/PureSaber/quant-data-kit.git`, resolving to
+commit `8f258f11be8e4d8edddcd41b79b817bd6c925970` through annotated tag object
+`87fc686dfb2d5ac2f86eca0132b3cdf05ff87c63`.
 
 Regenerate the lock only after reviewing dependency changes in `pyproject.toml`:
 
diff --git a/pyproject.toml b/pyproject.toml
index 7b080ba..adb309d 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "quant-execution"
-version = "0.5.0"
+version = "0.5.1"
 description = "Deterministic execution, matching, risk and ledger for PureSaber quant research"
 readme = "README.md"
 license = {text = "MIT"}
@@ -12,7 +12,7 @@ requires-python = ">=3.10"
 dependencies = [
     "pyarrow>=14.0",
     "jsonschema>=4.20",
-    "quant-data-kit @ git+https://github.com/PureSaber/quant-data-kit.git@v0.7.4",
+    "quant-data-kit @ git+https://github.com/PureSaber/quant-data-kit.git@v0.8.1",
 ]
 
 [project.optional-dependencies]
diff --git a/requirements.lock b/requirements.lock
index a175fb0..28d0e81 100644
--- a/requirements.lock
+++ b/requirements.lock
@@ -58,7 +58,7 @@ pytz==2026.3.post1
     # via pandas
 pyyaml==6.0.3
     # via quant-data-kit
-quant-data-kit @ git+https://github.com/PureSaber/quant-data-kit.git@v0.7.4
+quant-data-kit @ git+https://github.com/PureSaber/quant-data-kit.git@v0.8.1
     # via quant-execution (pyproject.toml)
 referencing==0.37.0
     # via
diff --git a/src/quant_execution/__init__.py b/src/quant_execution/__init__.py
index 90ffbdb..6748527 100644
--- a/src/quant_execution/__init__.py
+++ b/src/quant_execution/__init__.py
@@ -76,7 +76,7 @@
 )
 from quant_execution.state_machine import ALLOWED_TRANSITIONS, transition_order
 
-__version__ = "0.5.0"
+__version__ = "0.5.1"
 
 __all__ = [
     "ACCOUNT_SNAPSHOT_SCHEMA_ID",
diff --git a/tests/test_benchmark_replay.py b/tests/test_benchmark_replay.py
index ae8796d..3ad58fa 100644
--- a/tests/test_benchmark_replay.py
+++ b/tests/test_benchmark_replay.py
@@ -49,7 +49,7 @@ def test_matching_worker_contract_uses_explicit_five_percent_fill_density(tmp_pa
     assert result["artifact_cleanup"] == "none"
     assert result["artifact_files_removed"] == 0
     assert result["strict_verification_passed"] is True
-    assert result["dependencies"]["quant_data_kit"] == "0.7.4"
+    assert result["dependencies"]["quant_data_kit"] == "0.8.1"
     assert Path(result["artifact_path"]).is_dir()
     assert result["artifact_manifest_sha256"]
     assert result["artifact_file_sha256"]