diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index a8ec605..133b8d2 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -41,7 +41,7 @@ jobs:
       - uses: actions/checkout@v7
       - uses: dtolnay/rust-toolchain@1.88.0
         with:
-          components: clippy
+          components: rustfmt, clippy
       - run: make check
       - run: make release-check
 
diff --git a/CHANGELOG.md b/CHANGELOG.md
index c025e88..65d2346 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,10 +2,18 @@
 
 All notable changes to `sysprims-pty` are documented here.
 
+## 0.9.1 - 2026-09-01
+
+- First public release for the crates.io publication.
+- Adds Rustfmt to the tag release workflow package gate so `make check` is
+  fully provisioned on Rust 1.88.0.
+- Leaves `v0.9.0` as a non-release annotated tag with no GitHub release and no
+  crates.io publication.
+
 ## 0.9.0 - 2026-09-01
 
-- First public `sysprims-pty` release.
-- Publishes the `sysprims-pty` crate while retaining the `portable_pty`
+- Initial release-preparation tag. No GitHub release or crates.io publication.
+- Configures the `sysprims-pty` crate while retaining the `portable_pty`
   library target for migration compatibility.
 - Uses registry-resolvable `sysprims-session` and `sysprims-timeout` 0.2.3
   dependencies.
diff --git a/Cargo.lock b/Cargo.lock
index ef94d09..0ebe033 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -729,7 +729,7 @@ dependencies = [
 
 [[package]]
 name = "sysprims-pty"
-version = "0.9.0"
+version = "0.9.1"
 dependencies = [
  "anyhow",
  "bitflags 1.3.2",
diff --git a/Cargo.toml b/Cargo.toml
index 3972f54..a303ab3 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "sysprims-pty"
-version = "0.9.0"
+version = "0.9.1"
 authors = ["Wez Furlong", "3 Leaps, LLC"]
 edition = "2018"
 rust-version = "1.88.0"
@@ -21,7 +21,7 @@ include = [
     "LICENSE-MIT",
     "CHANGELOG.md",
     "RELEASE_NOTES.md",
-    "docs/releases/v0.9.0.md",
+    "docs/releases/v0.9.1.md",
     "src/**/*.rs",
     "tests/**/*.rs",
     "examples/**/*.rs",
diff --git a/README.md b/README.md
index cba2d8b..b0dcd7f 100644
--- a/README.md
+++ b/README.md
@@ -19,7 +19,7 @@ an owned, verifiable process lifecycle.
 
 The package name is `sysprims-pty`. The library target is `portable_pty`,
 so existing `portable_pty` imports can keep working after a package rename.
-The first public version coordinate is `0.9.0`.
+The first public version coordinate is `0.9.1`.
 
 ## What you can build
 
diff --git a/RELEASE_CHECKLIST.md b/RELEASE_CHECKLIST.md
index 5e42181..bf9ae2d 100644
--- a/RELEASE_CHECKLIST.md
+++ b/RELEASE_CHECKLIST.md
@@ -70,7 +70,7 @@ handled:
 Required local signing environment:
 
 - `SYSPRIMS_PTY_RELEASE_TAG`: release tag with the leading `v`, for example
-  `v0.9.0`.
+  `v0.9.1`.
 - `SYSPRIMS_PTY_MINISIGN_KEY`: minisign secret key path.
 - `SYSPRIMS_PTY_MINISIGN_PUB`: minisign public key path. If omitted, the
   tooling derives it from `SYSPRIMS_PTY_MINISIGN_KEY` by replacing `.key` with
diff --git a/RELEASE_NOTES.md b/RELEASE_NOTES.md
index b393d0b..e88381c 100644
--- a/RELEASE_NOTES.md
+++ b/RELEASE_NOTES.md
@@ -2,4 +2,5 @@
 
 Release-specific notes are kept in `docs/releases/`.
 
+- [v0.9.1](docs/releases/v0.9.1.md)
 - [v0.9.0](docs/releases/v0.9.0.md)
diff --git a/VERSION b/VERSION
index ac39a10..f374f66 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-0.9.0
+0.9.1
diff --git a/docs/releases/v0.9.0.md b/docs/releases/v0.9.0.md
index ee4a1b4..b509f73 100644
--- a/docs/releases/v0.9.0.md
+++ b/docs/releases/v0.9.0.md
@@ -1,24 +1,14 @@
 # sysprims-pty v0.9.0
 
-First public release of `sysprims-pty`.
+Non-release annotated tag retained for provenance.
 
 The crate provides cross-platform PTY APIs with sysprims-backed containment and
 keeps the library target named `portable_pty` for source-level migration from
 compatible callers.
 
-## Distribution
+## Status
 
-- Crate package: `sysprims-pty = "=0.9.0"`
-- Library import: `portable_pty`
-- License: MIT
+No GitHub release was published for this tag, and no crates.io package was
+published at `0.9.0`.
 
-## Release assets
-
-The GitHub release carries provenance assets for this source release:
-
-- `LICENSE-MIT`
-- CycloneDX SBOM
-- release notes
-- checksum manifests
-- checksum signatures
-- public signing keys
+The first public release coordinate is `v0.9.1`.
diff --git a/docs/releases/v0.9.1.md b/docs/releases/v0.9.1.md
new file mode 100644
index 0000000..97dd34c
--- /dev/null
+++ b/docs/releases/v0.9.1.md
@@ -0,0 +1,29 @@
+# sysprims-pty v0.9.1
+
+First public release for `sysprims-pty`.
+
+The crate provides cross-platform PTY APIs with sysprims-backed containment and
+keeps the library target named `portable_pty` for source-level migration from
+compatible callers.
+
+## Distribution
+
+- Crate package: `sysprims-pty = "=0.9.1"`
+- Library import: `portable_pty`
+- License: MIT
+
+## Release assets
+
+The GitHub release carries provenance assets for this source release:
+
+- `LICENSE-MIT`
+- CycloneDX SBOM
+- release notes
+- checksum manifests
+- checksum signatures
+- public signing keys
+
+## Notes
+
+The earlier `v0.9.0` tag is not a public release. It remains an annotated tag
+with no GitHub release and no crates.io publication.