repo: initial attempt at setting up CI with Spindle.

.tangled/workflows/build.yml

···
+when:
+  - event: ["push", "manual"]
+    branch: ["main"]
+
+engine: "nixery"
+
+# using the default values
+clone:
+  skip: false
+  depth: 1
+  submodules: false
+
+dependencies:
+  nixpkgs:
+    - skopeo
+
+# environment:
+
+steps:
+  - name: "Build Docker Image"
+    command: "nix build .#docker.x86-64-linux.default"
+  - name: "Push image to Fly.io registry"
+    command: >
+      skopeo --insecure-policy copy
+        docker-archive:./result 
+        docker://registry.fly.io/${APP_NAME}:latest 
+      --dest-creds x:"$FLY_ACCESS_TOKEN" 
+      --format v2s2
+
+    environment:
+      APP_NAME: "audquotes"

flake.nix

···
         in {
           packages = {
             default = rustApp;
-            docker = pkgs.dockerTools.streamLayeredImage {
+            docker = pkgs.dockerTools.buildLayeredImage {
               name = "localhost/${pkgName}";
               tag = "latest";
               contents = [ rustApp ];