FROM golang:1.24-alpine AS builder

RUN apk add --no-cache git

WORKDIR /app

COPY go.mod go.sum ./
RUN go mod download

COPY main.go ./
RUN go build -o sshserver main.go

FROM alpine:latest

RUN apk add --no-cache ca-certificates && mkdir -p /app

COPY --from=builder /app/sshserver /usr/local/bin/sshserver

EXPOSE 22

CMD ["/usr/local/bin/sshserver"]