diff --git a/.gitea/workflows/linux.yml b/.gitea/workflows/linux.yml
new file mode 100644
index 0000000..49d35b0
--- /dev/null
+++ b/.gitea/workflows/linux.yml
@@ -0,0 +1,40 @@
+name: Sized Linux checks
+
+on:
+  push:
+    branches: [main, sizequeen-scan-hardening]
+    paths: ['Cargo.toml', 'Cargo.lock', 'src/**', 'tests/**', 'benches/**', 'scripts/**', '.gitea/workflows/**']
+  pull_request:
+    branches: [main]
+    paths: ['Cargo.toml', 'Cargo.lock', 'src/**', 'tests/**', 'benches/**', 'scripts/**', '.gitea/workflows/**']
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+jobs:
+  linux-amd64:
+    name: Linux AMD64 / Rust 1.88.0
+    # Keep the existing shared runner limited to owner-triggered, same-repo code.
+    if: ${{ gitea.actor == 'gamertan' && (gitea.event_name != 'pull_request' || gitea.event.pull_request.head.repo.full_name == gitea.repository) }}
+    runs-on: himesan-node24
+    timeout-minutes: 20
+    container:
+      image: sha256:514512270649a85769c2b8ecfcc3a860d3a7da67c29b9b7b1cfe4c75de41d322
+      options: >-
+        --user 65532:65532
+        --tmpfs /tmp/sized-mount-test:rw,nosuid,nodev,noexec,size=16m,uid=65532,gid=65532,mode=0700
+        --tmpfs /tmp/sized-mount-test/foreign:rw,nosuid,nodev,noexec,size=16m,uid=65532,gid=65532,mode=0700
+    env:
+      CARGO_HOME: /tmp/sized-cargo
+      CARGO_BUILD_JOBS: '2'
+      SIZED_TEST_SOURCE: ${{ gitea.workspace }}
+      SIZED_TEST_MOUNT_ROOT: /tmp/sized-mount-test
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683
+        with:
+          persist-credentials: false
+      - name: Unprivileged Linux tests, real mount boundary, Clippy and release smoke
+        run: ./scripts/check-linux-container.sh
+      - name: Require an unchanged checkout
+        run: test -z "$(git status --porcelain=v1 --untracked-files=all)"
diff --git a/README.md b/README.md
index cedfbfc..fd00c94 100644
--- a/README.md
+++ b/README.md
@@ -170,6 +170,13 @@ removed on exit. Docker retains the reusable check images/build cache.
 can select a different toolchain image for an explicit compatibility check.
 These are backend checks; desktop X11/Wayland acceptance belongs to SizeQueen.
 
+Gitea's `Sized Linux checks` workflow runs the same checks natively on cliff-mads
+for main/review-branch source changes and owner-triggered, same-repository PRs.
+It uses a pinned Rust job image, UID 65532 and real tmpfs boundaries without
+Docker access inside the job. Fork contributions can run the local script;
+maintainers can bring reviewed changes onto a repository branch for CI.
+See SHIPMENT for runner-image setup. Documentation-only pushes skip builds.
+
 See [source review and release process](SHIPMENT.md) and the [live queue](TODO.md).
 
 ## License
diff --git a/SHIPMENT.md b/SHIPMENT.md
index fdd2646..450d073 100644
--- a/SHIPMENT.md
+++ b/SHIPMENT.md
@@ -23,9 +23,30 @@ in a separate PR so reviewers can distinguish behaviour changes from packaging.
    use the release steps below when explicitly authorized. Reconcile legacy
    GitLab download/package links before announcing a Gitea release.
 
-Use the same Linux check script in Gitea CI when a Docker-capable runner is
-configured. The current branch provides the local entry point; it does not
-configure a runner or enable automatic publishing.
+### Gitea Linux CI
+
+`.gitea/workflows/linux.yml` uses the existing `himesan-node24` label on
+cliff-mads, overriding the job image with the pinned Sized Rust runtime.
+The runner itself launches the two tmpfs mounts. Jobs have no Docker socket
+and run `scripts/check-linux-container.sh` as UID 65532, using the checked-out
+workspace as `SIZED_TEST_SOURCE`. Its tests, strict Clippy, formatting and
+optimized-binary smoke test are the same as the local Docker workflow.
+
+The runtime contains Rust 1.88.0, rustfmt/Clippy and Node for the pinned checkout
+action. On cliff-mads, rebuild it explicitly with:
+
+```bash
+ssh cliff-mads 'docker build --platform linux/amd64 --tag local/gamertan-ci:sized-rust188 -' < scripts/gitea-linux.Dockerfile
+ssh cliff-mads 'docker image inspect local/gamertan-ci:sized-rust188 --format "{{.Id}}"'
+```
+
+Review and update the workflow's image ID after an intentional rebuild; images
+stay local to the runner host. No runner labels, global isolation settings or
+publishing credentials are required. Repository Actions must be enabled.
+Only owner-triggered, same-repository code runs on this shared homelab runner.
+Source changes on main/the review branch and PRs to main trigger checks;
+documentation-only pushes skip builds. Manual dispatch is also available.
+This workflow does not publish or tag releases.
 
 ## 1. Versioning and Tagging
 
diff --git a/TODO.md b/TODO.md
index 918622a..876d328 100644
--- a/TODO.md
+++ b/TODO.md
@@ -19,6 +19,9 @@ Keep the existing CLI useful and preserve the GPL-3.0-only license.
 - [x] Commit the scanner hardening and Linux check tooling; push the existing
   `sizequeen-scan-hardening` review branch. Remote equality is verified.
   Open a PR when ready; release/tag/package publication remains separate.
+- [ ] Enable repository Actions and run the same Linux checks on the existing
+  cliff-mads runner. Keep its container isolation and other jobs unchanged;
+  verify a real workflow result before treating CI as proven.
 
 ## Proposed next work
 
@@ -36,6 +39,14 @@ authorized; see `SHIPMENT.md` for source review and the separate release process
 
 ## Resume note
 
+Current CI checkpoint: repository Actions is enabled. The existing cliff-mads
+runner is healthy (`gitea-runner v3.1.0`, native AMD64). The workflow reuses its
+`himesan-node24` label and a separately built Rust/Node image; runner configuration,
+other jobs and repository visibility are unchanged. The image bootstrap probe
+verified UID 65532, workspace-volume ownership, Rust 1.88.0/Node 24.19.0 and
+distinct tmpfs devices. Actual Gitea checkout/check execution is still pending;
+do not call CI proven until the real workflow completes.
+
 Linux validation and the requested remote review branch are complete.
 Scanner hardening is `8b177e2`; repeatable Linux checks and equivalent format
 interpolations are `988aad9`. Both implementation commits are pushed to
diff --git a/scripts/check-linux-container.sh b/scripts/check-linux-container.sh
index 2bedbf4..a8b3544 100755
--- a/scripts/check-linux-container.sh
+++ b/scripts/check-linux-container.sh
@@ -10,8 +10,9 @@ cargo --version
 # Only source inputs are copied. Cargo output and all fixtures disappear with
 # the container; the host checkout is read-only and no personal tree is scanned.
 check_root=$(mktemp -d /tmp/sized-check.XXXXXX)
-cp /source/Cargo.toml /source/Cargo.lock "$check_root/"
-cp -R /source/src /source/tests /source/benches "$check_root/"
+source_root=${SIZED_TEST_SOURCE:-/source}
+cp "$source_root/Cargo.toml" "$source_root/Cargo.lock" "$check_root/"
+cp -R "$source_root/src" "$source_root/tests" "$source_root/benches" "$check_root/"
 cd "$check_root"
 cargo fmt --all -- --check
 cargo test --locked
diff --git a/scripts/gitea-linux.Dockerfile b/scripts/gitea-linux.Dockerfile
new file mode 100644
index 0000000..26572b9
--- /dev/null
+++ b/scripts/gitea-linux.Dockerfile
@@ -0,0 +1,10 @@
+# Node supports the pinned checkout action; application code remains Rust.
+FROM node:24-bookworm@sha256:934240a162082fd8b8a2f90cd5114446443f1eba1c5378f6687167ca405e6584 AS node-runtime
+FROM rust:1.88.0-bookworm@sha256:af306cfa71d987911a781c37b59d7d67d934f49684058f96cf72079c3626bfe0
+RUN rustup component add rustfmt clippy
+COPY --from=node-runtime /usr/local/bin/node /usr/local/bin/node
+# A new runner workspace volume inherits this ownership. No setuid step or
+# Docker socket is needed in jobs, even with all capabilities dropped.
+RUN mkdir -p /workspace && chown 65532:65532 /workspace
+USER 65532:65532
+WORKDIR /workspace