try building

.gitea/workflows/build.yml

@@ -0,0 +1,17 @@
+name: Build image
+run-name: ${{ gitea.actor }} is building an image
+on: [push]
+
+jobs:
+  runs-on: alpine
+  steps:
+    - uses: https://github.com/actions/checkout@v4
+    - name: Set up Docker Buildx
+        uses: https://github.com/docker/setup-buildx-action@v3            
+    - name: Build and push Docker image
+      uses: https://github.com/docker/build-push-action@v5
+      with:
+        context: .
+        file: ./Dockerfile
+        push: true
+        tags: "hal.mafoo.org.uk/mafoo.org.uk/mythic-dns:${{gitea.sha}},hal.mafoo.org.uk/mafoo.org.uk/mythic-dns:latest"

LICENSE

@@ -0,0 +1,19 @@
+Copyright (c) 2023 Matthew Slowe (foo@mafoo.org.uk)
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.