---
title: Containerize a Golang application
linkTitle: Containerize your app
weight: 20
keywords: go, golang, containerize, initialize
description: Learn how to containerize a Golang application.
---

Containerization helps you bundle the application and its dependencies into a single package called a container. This package can run on any platform without worrying about the environment. In this section, you will learn how to containerize a Golang application using Docker.

To containerize a Golang application, you first need to create a Dockerfile. The Dockerfile contains instructions to build and run the application in a container. Also, when creating a Dockerfile, you can follow different sets of best practices to optimize the image size and make it more secure.

## Creating a Dockerfile

Create a new file named `Dockerfile` in the root directory of your Golang application. The Dockerfile contains instructions to build and run the application in a container.

The following is a Dockerfile for a Golang application. You will also find this file in the `go-prometheus-monitoring` directory.

```dockerfile
# Use the official Golang image as the base
FROM golang:1.24-alpine AS builder

# Set environment variables
ENV CGO_ENABLED=0 \
    GOOS=linux \
    GOARCH=amd64

# Set working directory inside the container
WORKDIR /build

# Copy go.mod and go.sum files for dependency installation
COPY go.mod go.sum ./

# Download dependencies
RUN go mod download

# Copy the entire application source
COPY . .

# Build the Go binary
RUN go build -o /app .

# Final lightweight stage
FROM alpine:3.21 AS final

# Copy the compiled binary from the builder stage
COPY --from=builder /app /bin/app

# Expose the application's port
EXPOSE 8000

# Run the application
CMD ["bin/app"]
```

## Understanding the Dockerfile

The Dockerfile consists of two stages:

1. **Build stage**: This stage uses the official Golang image as the base and sets the necessary environment variables. It also sets the working directory inside the container, copies the `go.mod` and `go.sum` files for dependency installation, downloads the dependencies, copies the entire application source, and builds the Go binary.

    You use the `golang:1.24-alpine` image as the base image for the build stage. The `CGO_ENABLED=0` environment variable disables CGO, which is useful for building static binaries. You also set the `GOOS` and `GOARCH` environment variables to `linux` and `amd64`, respectively, to build the binary for the Linux platform.