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Dockerfile

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+# syntax=docker/dockerfile:1
+
+# ---- build stage ----
+FROM golang:1.27-alpine AS build
+WORKDIR /src
+
+# cache deps first
+COPY go.mod go.sum ./
+RUN go mod download
+
+COPY . .
+RUN CGO_ENABLED=0 GOOS=linux go build -ldflags="-s -w" -o /palette .
+
+# ---- runtime stage ----
+FROM alpine:3.20
+
+# non-root user
+RUN adduser -D -u 10001 palette
+
+COPY --from=build /palette /usr/local/bin/palette
+
+USER palette
+WORKDIR /data
+
+ENV PALETTE_ADDR=":8080" \
+    PALETTE_DB="/data/palette.db"
+
+EXPOSE 8080
+VOLUME /data
+
+HEALTHCHECK --interval=30s --timeout=3s --retries=3 \
+  CMD wget -qO- http://127.0.0.1:8080/ >/dev/null 2>&1 || exit 1
+
+ENTRYPOINT ["palette"]