diff --git a/CHANGELOG.md b/CHANGELOG.md
index 24fc1c0..5a2681f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,16 @@ The notable changes of every release. The section of a version is the text of it
 
 ## [Unreleased]
 
+## [0.3.0] - 2026-10-06
+
+POLL delivery that survives restarts and runs on several instances: acknowledgements wait in a
+store, optionally in the database, long polling keeps a request outstanding, and a SET is claimed
+while its handlers run so that two instances never acknowledge a SET one of them failed on.
+The JDBC schema gained a column and a table; migration scripts and startup upgrades come with it.
+Handlers get typed access to CAEP and RISC events with `SsfCaepEventHandler` and `SsfRiscEventHandler`,
+and the documentation now says in plain words that processing is at least once, with `idempotencyKey()`
+as the key for a handler's side effects.
+
 ### Added
 
 - POLL delivery keeps the acknowledgements and error reports it owes the transmitter in an
@@ -118,6 +128,7 @@ Java library and as a Spring Boot 4.1 starter.
 - The framework-free modules are Java modules; every artifact is signed, carries a CycloneDX
   SBOM and a self-contained POM.
 
-[Unreleased]: https://github.com/easyssf/easyssf/compare/v0.2.0...HEAD
+[Unreleased]: https://github.com/easyssf/easyssf/compare/v0.3.0...HEAD
+[0.3.0]: https://github.com/easyssf/easyssf/compare/v0.2.0...v0.3.0
 [0.2.0]: https://github.com/easyssf/easyssf/compare/v0.1.0...v0.2.0
 [0.1.0]: https://github.com/easyssf/easyssf/releases/tag/v0.1.0
diff --git a/README.md b/README.md
index 08c3f96..d7244dc 100644
--- a/README.md
+++ b/README.md
@@ -80,7 +80,7 @@ which a build has to enable with `<snapshots><enabled>true</enabled></snapshots>
 <dependency>
     <groupId>org.easyssf</groupId>
     <artifactId>easyssf-receiver-spring-boot-starter</artifactId>
-    <version>0.2.0</version>
+    <version>0.3.0</version>
 </dependency>
 ```
 
@@ -127,7 +127,7 @@ configuration reference.
 <dependency>
     <groupId>org.easyssf</groupId>
     <artifactId>easyssf-receiver</artifactId>
-    <version>0.2.0</version>
+    <version>0.3.0</version>
 </dependency>
 ```
 
@@ -289,7 +289,7 @@ Spring Boot modules are automatic modules.
 <dependency>
     <groupId>org.easyssf</groupId>
     <artifactId>easyssf-receiver</artifactId>
-    <version>0.2.0</version>
+    <version>0.3.0</version>
 </dependency>
 ```
 
@@ -374,7 +374,7 @@ stream management and poll endpoints. The tests of easyssf itself use it.
 <dependency>
     <groupId>org.easyssf</groupId>
     <artifactId>easyssf-test</artifactId>
-    <version>0.2.0</version>
+    <version>0.3.0</version>
     <scope>test</scope>
 </dependency>
 ```
diff --git a/easyssf-core/pom.xml b/easyssf-core/pom.xml
index c96cf4e..647b843 100644
--- a/easyssf-core/pom.xml
+++ b/easyssf-core/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>org.easyssf</groupId>
         <artifactId>easyssf-parent</artifactId>
-        <version>0.3.0-SNAPSHOT</version>
+        <version>0.4.0-SNAPSHOT</version>
     </parent>
     <artifactId>easyssf-core</artifactId>
     <name>easyssf-core</name>
diff --git a/easyssf-receiver-jdbc/pom.xml b/easyssf-receiver-jdbc/pom.xml
index 6facec4..ee9f7fa 100644
--- a/easyssf-receiver-jdbc/pom.xml
+++ b/easyssf-receiver-jdbc/pom.xml
@@ -6,7 +6,7 @@
     <parent>
         <groupId>org.easyssf</groupId>
         <artifactId>easyssf-parent</artifactId>
-        <version>0.3.0-SNAPSHOT</version>
+        <version>0.4.0-SNAPSHOT</version>
     </parent>
 
     <artifactId>easyssf-receiver-jdbc</artifactId>
diff --git a/easyssf-receiver-spring-boot-autoconfigure/pom.xml b/easyssf-receiver-spring-boot-autoconfigure/pom.xml
index ffa276a..79e800c 100644
--- a/easyssf-receiver-spring-boot-autoconfigure/pom.xml
+++ b/easyssf-receiver-spring-boot-autoconfigure/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>org.easyssf</groupId>
         <artifactId>easyssf-parent</artifactId>
-        <version>0.3.0-SNAPSHOT</version>
+        <version>0.4.0-SNAPSHOT</version>
     </parent>
     <artifactId>easyssf-receiver-spring-boot-autoconfigure</artifactId>
     <name>easyssf-receiver-spring-boot-autoconfigure</name>
diff --git a/easyssf-receiver-spring-boot-conformance-tests/pom.xml b/easyssf-receiver-spring-boot-conformance-tests/pom.xml
index a9d140d..2f848e3 100644
--- a/easyssf-receiver-spring-boot-conformance-tests/pom.xml
+++ b/easyssf-receiver-spring-boot-conformance-tests/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>org.easyssf</groupId>
         <artifactId>easyssf-parent</artifactId>
-        <version>0.3.0-SNAPSHOT</version>
+        <version>0.4.0-SNAPSHOT</version>
     </parent>
     <artifactId>easyssf-receiver-spring-boot-conformance-tests</artifactId>
     <name>easyssf-receiver-spring-boot-conformance-tests</name>
diff --git a/easyssf-receiver-spring-boot-examples/example-oidc-client/pom.xml b/easyssf-receiver-spring-boot-examples/example-oidc-client/pom.xml
index 46262fe..e8f72b9 100644
--- a/easyssf-receiver-spring-boot-examples/example-oidc-client/pom.xml
+++ b/easyssf-receiver-spring-boot-examples/example-oidc-client/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>org.easyssf</groupId>
         <artifactId>easyssf-receiver-spring-boot-examples</artifactId>
-        <version>0.3.0-SNAPSHOT</version>
+        <version>0.4.0-SNAPSHOT</version>
     </parent>
     <artifactId>example-oidc-client</artifactId>
     <name>example-oidc-client</name>
diff --git a/easyssf-receiver-spring-boot-examples/example-resource-server/pom.xml b/easyssf-receiver-spring-boot-examples/example-resource-server/pom.xml
index 09c7141..5024208 100644
--- a/easyssf-receiver-spring-boot-examples/example-resource-server/pom.xml
+++ b/easyssf-receiver-spring-boot-examples/example-resource-server/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>org.easyssf</groupId>
         <artifactId>easyssf-receiver-spring-boot-examples</artifactId>
-        <version>0.3.0-SNAPSHOT</version>
+        <version>0.4.0-SNAPSHOT</version>
     </parent>
     <artifactId>example-resource-server</artifactId>
     <name>example-resource-server</name>
diff --git a/easyssf-receiver-spring-boot-examples/example-scim-provisioning/pom.xml b/easyssf-receiver-spring-boot-examples/example-scim-provisioning/pom.xml
index 4fd9cc9..7a2ed49 100644
--- a/easyssf-receiver-spring-boot-examples/example-scim-provisioning/pom.xml
+++ b/easyssf-receiver-spring-boot-examples/example-scim-provisioning/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>org.easyssf</groupId>
         <artifactId>easyssf-receiver-spring-boot-examples</artifactId>
-        <version>0.3.0-SNAPSHOT</version>
+        <version>0.4.0-SNAPSHOT</version>
     </parent>
     <artifactId>example-scim-provisioning</artifactId>
     <name>example-scim-provisioning</name>
diff --git a/easyssf-receiver-spring-boot-examples/pom.xml b/easyssf-receiver-spring-boot-examples/pom.xml
index d138e27..6a9dcfd 100644
--- a/easyssf-receiver-spring-boot-examples/pom.xml
+++ b/easyssf-receiver-spring-boot-examples/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>org.easyssf</groupId>
         <artifactId>easyssf-parent</artifactId>
-        <version>0.3.0-SNAPSHOT</version>
+        <version>0.4.0-SNAPSHOT</version>
     </parent>
     <artifactId>easyssf-receiver-spring-boot-examples</artifactId>
     <name>easyssf-receiver-spring-boot-examples</name>
diff --git a/easyssf-receiver-spring-boot-starter/README.md b/easyssf-receiver-spring-boot-starter/README.md
index 2a78078..6044f1d 100644
--- a/easyssf-receiver-spring-boot-starter/README.md
+++ b/easyssf-receiver-spring-boot-starter/README.md
@@ -10,7 +10,7 @@ Events, the test support.
 <dependency>
     <groupId>org.easyssf</groupId>
     <artifactId>easyssf-receiver-spring-boot-starter</artifactId>
-    <version>0.2.0</version>
+    <version>0.3.0</version>
 </dependency>
 ```
 
diff --git a/easyssf-receiver-spring-boot-starter/pom.xml b/easyssf-receiver-spring-boot-starter/pom.xml
index abb8dba..d8dc7fa 100644
--- a/easyssf-receiver-spring-boot-starter/pom.xml
+++ b/easyssf-receiver-spring-boot-starter/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>org.easyssf</groupId>
         <artifactId>easyssf-parent</artifactId>
-        <version>0.3.0-SNAPSHOT</version>
+        <version>0.4.0-SNAPSHOT</version>
     </parent>
     <artifactId>easyssf-receiver-spring-boot-starter</artifactId>
     <name>easyssf-receiver-spring-boot-starter</name>
diff --git a/easyssf-receiver/pom.xml b/easyssf-receiver/pom.xml
index 125de20..b1d0e54 100644
--- a/easyssf-receiver/pom.xml
+++ b/easyssf-receiver/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>org.easyssf</groupId>
         <artifactId>easyssf-parent</artifactId>
-        <version>0.3.0-SNAPSHOT</version>
+        <version>0.4.0-SNAPSHOT</version>
     </parent>
     <artifactId>easyssf-receiver</artifactId>
     <name>easyssf-receiver</name>
diff --git a/easyssf-test-conformance/pom.xml b/easyssf-test-conformance/pom.xml
index fc2ed01..a791f60 100644
--- a/easyssf-test-conformance/pom.xml
+++ b/easyssf-test-conformance/pom.xml
@@ -6,7 +6,7 @@
     <parent>
         <groupId>org.easyssf</groupId>
         <artifactId>easyssf-parent</artifactId>
-        <version>0.3.0-SNAPSHOT</version>
+        <version>0.4.0-SNAPSHOT</version>
     </parent>
 
     <artifactId>easyssf-test-conformance</artifactId>
diff --git a/easyssf-test/pom.xml b/easyssf-test/pom.xml
index d768500..9c4d920 100644
--- a/easyssf-test/pom.xml
+++ b/easyssf-test/pom.xml
@@ -6,7 +6,7 @@
     <parent>
         <groupId>org.easyssf</groupId>
         <artifactId>easyssf-parent</artifactId>
-        <version>0.3.0-SNAPSHOT</version>
+        <version>0.4.0-SNAPSHOT</version>
     </parent>
 
     <artifactId>easyssf-test</artifactId>
diff --git a/pom.xml b/pom.xml
index 8096d2e..b0310de 100644
--- a/pom.xml
+++ b/pom.xml
@@ -6,7 +6,7 @@
 
     <groupId>org.easyssf</groupId>
     <artifactId>easyssf-parent</artifactId>
-    <version>0.3.0-SNAPSHOT</version>
+    <version>0.4.0-SNAPSHOT</version>
     <packaging>pom</packaging>
     <name>easyssf</name>
     <description>Building blocks for the OpenID Shared Signals Framework (SSF)</description>
@@ -65,7 +65,7 @@
              the newest JDK: -Dbytebuddy.experimental=true -->
         <bytebuddy.experimental>false</bytebuddy.experimental>
         <!-- reproducible builds: the timestamp of the files in the jars, updated for every release -->
-        <project.build.outputTimestamp>2026-10-04T13:28:33Z</project.build.outputTimestamp>
+        <project.build.outputTimestamp>2026-10-05T23:58:41Z</project.build.outputTimestamp>
 
         <!-- All modules build against the versions of the Spring Boot BOM, imported below.
              The plain modules (easyssf-core, easyssf-receiver) do not depend on Spring: