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# FROM — the base image to build on
FROM node:20-alpine

# WORKDIR — set the working directory inside the image
WORKDIR /app

# COPY dependency files first (for better layer caching)
COPY package*.json ./
# RUN — execute a command during the BUILD (install dependencies)
RUN npm install

# COPY the rest of the application code
COPY . .

# EXPOSE — document the port the app listens on
EXPOSE 3000

# CMD — the command to run when a CONTAINER starts
CMD ["node", "server.js"]