diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7493eac..dc4e51e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,10 +6,25 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 Entries for unreleased work are not written here directly. Each issue drops a
-fragment in [`changelog.d/`](https://github.com/riddler/statifier_persistence/blob/v0.23.0/changelog.d/README.md); the fragments are assembled
+fragment in [`changelog.d/`](https://github.com/riddler/statifier_persistence/blob/v0.23.1/changelog.d/README.md); the fragments are assembled
 into a version section at release. See that README for the format and for when a
 change warrants an entry at all.
 
+## [0.23.1] 2026-09-29
+
+Patch release: `StatifierPersistence.Testing.StorageConformance` no
+longer deadlocks when two or more modules run it asynchronously against
+one Postgres database. The package's own adapters answer what they
+answered in 0.23.0.
+
+Upgrading: nothing to change. No schema migration, the `statifier`
+floor stays `~> 2.9`, and no answer a host matches is added or
+removed. See `docs/upgrading.md`, "0.22 to 0.23".
+
+### Fixed
+
+- `StatifierPersistence.Testing.StorageConformance` retires only chart hashes derived from the using module's name, so two or more modules running it asynchronously against one Postgres database no longer deadlock (`40P01`) in the tombstone-check case or in the cases that retire a hash after a create's or a migration's first check.
+
 ## [0.23.0] 2026-09-28
 
 Feature release: under the default serialization strategy, a create,
diff --git a/changelog.d/sp-gbyk.md b/changelog.d/sp-gbyk.md
deleted file mode 100644
index 4219c6a..0000000
--- a/changelog.d/sp-gbyk.md
+++ /dev/null
@@ -1,3 +0,0 @@
-### Fixed
-
-- `StatifierPersistence.Testing.StorageConformance` retires only chart hashes derived from the using module's name, so two or more modules running it asynchronously against one Postgres database no longer deadlock (`40P01`) in the tombstone-check case or in the cases that retire a hash after a create's or a migration's first check.
diff --git a/docs/upgrading.md b/docs/upgrading.md
index 6c87af0..0358e06 100644
--- a/docs/upgrading.md
+++ b/docs/upgrading.md
@@ -362,6 +362,8 @@ Schema: **NONE**. The `statifier` floor stays `~> 2.9`.
 
 ## 0.22 to 0.23
 
+### 0.23.0
+
 Schema: **NONE**. The `statifier` floor stays `~> 2.9`.
 
 - **If a create, migration or tree migration can run while the same
@@ -403,3 +405,15 @@ Schema: **NONE**. The `statifier` floor stays `~> 2.9`.
   step answers the same error and the rollback, if any, is yours. A
   budget-exhausted step still commits its `:failed` record. A host whose
   position saves never fail: **NONE**.
+
+### 0.23.1
+
+**NONE.** Schema: **NONE**, the `statifier` floor stays `~> 2.9`, and no
+answer a host matches is added or removed.
+
+- **If you run `StatifierPersistence.Testing.StorageConformance` from two
+  or more async test modules against one Postgres database**, the suite
+  no longer deadlocks (`40P01`) in the tombstone-check case or in the
+  cases that retire a hash after a create's or a migration's first
+  check: each module that uses the suite now retires chart hashes of its
+  own, derived from the module's name. Nothing in your suite changes.
diff --git a/mix.exs b/mix.exs
index c9fcba2..a1b5f56 100644
--- a/mix.exs
+++ b/mix.exs
@@ -1,7 +1,7 @@
 defmodule StatifierPersistence.MixProject do
   use Mix.Project
 
-  @version "0.23.0"
+  @version "0.23.1"
   @source_url "https://github.com/riddler/statifier_persistence"
 
   def project do