diff --git a/CHANGELOG.md b/CHANGELOG.md
index 031ff3f..9fff611 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,16 @@
 # Changelog
 
+## [1.0.0](https://github.com/OctopusDeploy/create-release-buildkite-plugin/compare/v0.1.1...v1.0.0) (2026-08-24)
+
+
+### ⚠ BREAKING CHANGES
+
+* `api_key` now takes the API key itself rather than the name of an environment variable to eval. `what_if`, `packages_folder` and `package_prerelease` are rejected, because the octopus CLI has no equivalent and silently ignoring them would change what a build does. config_file, log_level, timeout, proxy, proxy_username, proxy_password and ignore_ssl_errors warn and are ignored. OCTOPUS_CLI_SERVER and OCTOPUS_CLI_API_KEY are no longer read.
+
+### Features
+
+* migrate from the retired octo CLI to the octopus CLI ([a6688fe](https://github.com/OctopusDeploy/create-release-buildkite-plugin/commit/a6688fe657c5fbb0c33e2f65618a364572fb5fee))
+
 ### [0.1.1](https://github.com/OctopusDeploy/create-release-buildkite-plugin/compare/v0.1.0...v0.1.1) (2022-02-21)
 
 
diff --git a/README.md b/README.md
index 39a36c5..f6b34be 100644
--- a/README.md
+++ b/README.md
@@ -28,7 +28,7 @@ steps:
       - OctopusDeploy/octopus-login#v1.0.0:
           server: "https://my.octopus.app"
           service_account_id: "d5de4670-4678-4c08-9479-09555cd6ccbb"
-      - OctopusDeploy/create-release#v0.1.1:
+      - OctopusDeploy/create-release#v1.0.0
           project: "HelloWorld"
 ```
 
@@ -48,7 +48,7 @@ Incorporate the following step in your `pipeline.yml` to create a release in Oct
 steps:
   - label: ":octopus-deploy: Create a release in Octopus Deploy"
     plugins:
-      - OctopusDeploy/create-release#v0.1.1:
+      - OctopusDeploy/create-release#v1.0.0
           api_key: "${MY_OCTOPUS_API_KEY}"
           project: "HelloWorld"
           server: "${MY_OCTOPUS_SERVER}"
@@ -60,7 +60,7 @@ steps:
 steps:
   - label: ":octopus-deploy: Create a release in Octopus Deploy"
     plugins:
-      - OctopusDeploy/create-release#v0.1.1:
+      - OctopusDeploy/create-release#v1.0.0
           api_key: "${MY_OCTOPUS_API_KEY}"
           project: "HelloWorld"
           release_number: "1.0.3"
@@ -75,7 +75,7 @@ steps:
 steps:
   - label: ":octopus-deploy: Create a release in Octopus Deploy"
     plugins:
-      - OctopusDeploy/create-release#v0.1.1:
+      - OctopusDeploy/create-release#v1.0.0
           api_key: "${MY_OCTOPUS_API_KEY}"
           git_ref: "main"
           project: "HelloWorld"
@@ -91,7 +91,7 @@ steps:
 steps:
   - label: ":octopus-deploy: Create a release in Octopus Deploy"
     plugins:
-      - OctopusDeploy/create-release#v0.1.1:
+      - OctopusDeploy/create-release#v1.0.0
           api_key: "${MY_OCTOPUS_API_KEY}"
           default_package_version: "1.0.1"
           project: "HelloWorld"
@@ -105,7 +105,7 @@ steps:
 steps:
   - label: ":octopus-deploy: Create a release in Octopus Deploy"
     plugins:
-      - OctopusDeploy/create-release#v0.1.1:
+      - OctopusDeploy/create-release#v1.0.0
           api_key: "${MY_OCTOPUS_API_KEY}"
           packages:
             - "StepA:1.0.1"
@@ -121,7 +121,7 @@ steps:
 steps:
   - label: ":octopus-deploy: Create a release in Octopus Deploy"
     plugins:
-      - OctopusDeploy/create-release#v0.1.1:
+      - OctopusDeploy/create-release#v1.0.0
           api_key: "${MY_OCTOPUS_API_KEY}"
           packages:
             - "StepA:Acme.Web:1.0.0"
diff --git a/version.txt b/version.txt
index 17e51c3..3eefcb9 100644
--- a/version.txt
+++ b/version.txt
@@ -1 +1 @@
-0.1.1
+1.0.0