Dive — Explore Docker Image Layers and Optimize Size

What it is

Dive is a CLI tool for exploring Docker image contents layer by layer. It shows exactly what files were added, modified, or removed in each layer, identifies wasted space from files that are added then deleted in subsequent layers, and provides an efficiency score. Dive helps you optimize Dockerfiles for smaller, more efficient container images.

Dive is for DevOps engineers and backend developers who build Docker images and want to reduce image size, speed up deployments, and lower storage costs.

The project is actively maintained with regular releases and a growing user community. Documentation covers common use cases, and the open-source nature means you can inspect the source code, contribute fixes, and adapt the tool to your specific requirements.

How it saves time or tokens

Without Dive, debugging large Docker images requires guessing which layer added unnecessary files. docker history shows layer sizes but not contents. Dive opens each layer in a file browser, showing the full filesystem diff. You can identify a 500MB layer caused by a package cache that should have been cleaned in the same RUN instruction.

How to use

1. Install Dive via brew, apt, or download the binary.
2. Run dive <image> to analyze any Docker image.
3. Navigate layers with arrow keys and inspect the file tree to find optimization opportunities.

Example

# Install Dive
brew install dive          # macOS
curl -OL https://github.com/wagoodman/dive/releases/download/v0.12.0/dive_0.12.0_linux_amd64.deb
sudo dpkg -i dive_0.12.0_linux_amd64.deb  # Linux

# Analyze an image
dive nginx:latest

# Analyze a locally built image
docker build -t myapp .
dive myapp

# CI mode: fail if efficiency is below threshold
CI=true dive myapp --highestWastedBytes 50MB

Related on TokRepo

• AI Tools for DevOps -- Docker and container optimization tools
• AI Tools for Self-Hosted -- Self-hosted infrastructure tooling

Common pitfalls

• Dive reads the image from the Docker daemon. If the image is only in a remote registry, pull it first with docker pull before running Dive.
• Multi-stage builds can confuse the layer view. Dive shows all layers from the final stage. Intermediate stages are not visible unless you analyze them separately.
• The CI mode flag --highestWastedBytes uses string values like '50MB'. Passing a raw number without units causes Dive to misinterpret the threshold.

Before adopting this tool, evaluate whether it fits your team's existing workflow. Read the official documentation thoroughly, and start with a small proof-of-concept rather than a full migration. Community forums, GitHub issues, and Stack Overflow are valuable resources when you encounter edge cases not covered in the documentation.