slimdock

A CI-friendly Docker image analyzer. Inspect layers, detect waste, find secrets, and enforce best practices — all from the command line, no daemon required.

Install

cargo install slimdock

Or via install script:

curl -sSL https://raw.githubusercontent.com/user/slimdock/main/install.sh | sh

Quickstart

$ slimdock analyze nginx:latest

Image: nginx:latest
Size: 187 MB (compressed: 64 MB)
Layers: 7

Layer  Base Image          Size     Command
─────  ──────────────────  ───────  ──────────────────────────────
1      debian:bookworm     74.8 MB  apt-get update && apt-get install -y ...
2      (scratch)           2.1 MB   COPY nginx.conf /etc/nginx/
3      (scratch)           0.8 MB   COPY html/ /usr/share/nginx/html/
...

Waste: 12.4 MB (6.6%)
  - Build artifacts left in image: 8.2 MB
  - Unused dependencies: 4.2 MB

Commands

Command	Description
analyze	Full image analysis: layers, sizes, waste breakdown
waste	Show only wasted space with cleanup suggestions
secrets	Scan for leaked credentials, keys, and tokens
suggest	Optimization recommendations for Dockerfile/labels
check	CI gate — exit non-zero if issues are found

JSON Output

All commands support --format json for CI pipeline integration:

slimdock check myapp:latest --format json

{
  "image": "myapp:latest",
  "passed": false,
  "issues": [
    {"severity": "warn", "message": "Image has 3.2 MB of wasted space"},
    {"severity": "error", "message": "Hardcoded API key found in layer 2"}
  ]
}

Exit Codes

Code	Meaning
0	Success
1	Error (invalid input, etc)
2	Check failed (issues found)

Comparison

Feature	slimdock	dive
Daemon required	No	Yes (Docker daemon)
CI-friendly	✅ exit codes + JSON	❌ TUI-only
JSON output	✅	❌
Exit codes for gates	✅	❌
Secret scanning	✅	❌
Multi-platform	✅ static binaries	Docker image only
License	MIT/Apache-2.0	MIT

License

Licensed under either of MIT or Apache 2.0 at your option.