flake plus docker cli metadata

Dockerfile

@@ -1,20 +1,29 @@
-FROM golang:1.19-alpine AS build
+# syntax = docker/dockerfile:1.4
+FROM nixos/nix:latest AS builder
+
+WORKDIR /tmp/build
+RUN mkdir /tmp/nix-store-closure
+
+RUN \
+    --mount=type=cache,target=/nix,from=nixos/nix:latest,source=/nix \
+    --mount=type=cache,target=/root/.cache \
+    --mount=type=bind,target=/tmp/build \
+    <<EOF 
+  ls -l /nix/store | wc
+  nix \
+    --extra-experimental-features "nix-command flakes" \
+    --extra-substituters "http://host.docker.internal?priority=10" \
+    --option filter-syscalls false \
+    --show-trace \
+    --log-format raw \
+    build . --out-link /tmp/output/result
+  cp -R $(nix-store -qR /tmp/output/result) /tmp/nix-store-closure
+EOF
+
+FROM scratch
 
 WORKDIR /app
 
-COPY go.mod ./
-COPY go.sum ./
-
-RUN go mod download
-
-COPY main.go ./
-COPY docker/ ./docker/
-COPY babashka/ ./babashka/
-
-RUN CGO_ENABLED=0 go build -ldflags "-s -w" -o babashka-pod-docker
-
-FROM alpine:3.17
-ARG version
-COPY repository/ /root/.babashka/pods/repository
-COPY --from=build /app/babashka-pod-docker /root/.babashka/pods/repository/docker/babashka-pod-docker/0.1.0
-RUN chmod 755 /root/.babashka/pods/repository/docker/babashka-pod-docker/0.1.0/babashka-pod-docker
+COPY --from=builder /tmp/nix-store-closure /nix/store
+COPY --from=builder /tmp/output/ /app/
+ENTRYPOINT ["/app/result/bin/babashka-pod-docker"]