leanBuildDocker

README

leanBuildDocker

A deterministic CLI that statically analyzes a Go project and generates an optimized Dockerfile, .dockerignore, and decision report — no code execution.

$ lbd
Detected: Go 1.23 (confidence: 1.0)
Analyzed: 2 direct dependencies, no CGO, no vendoring
Wrote: Dockerfile, .dockerignore, .lbd-report.md

The resulting image for a typical Go API lands in the 15–30 MB range using distroless/static, instead of the 800 MB+ common in naive Dockerfiles.

Install

go install github.com/VictorM0nteiro/leanBuildDocker/cmd/lbd@latest

Or grab a prebuilt binary from Releases.

Usage

# Generate a Dockerfile in the current project
lbd

# Point at a different directory
lbd --target ./services/api

# Overwrite existing artifacts
lbd --force

# Build the image and run a smoke test (requires Docker)
lbd --validate

# Diagnose an existing project + Dockerfile
lbd doctor

Main flags:

Flag	Description
--target, -t	Project directory (default: cwd)
--force, -f	Overwrite existing Dockerfile / .dockerignore / .lbd-report.md
--validate	After generating, run docker build + smoke test
--keep	Keep the validation image instead of removing it
--verbose, -v	Verbose logging

How it works

A 5-stage pipeline; each stage only reads the previous stage's typed output:

Scanner → Detector → Analyzer → Planner → Renderer
                         ↑
                   Knowledge Base (embedded YAML)

• No CGO + no vendoring: golang:<ver>-alpine for build, distroless/static for runtime.
• CGO required: golang:<ver> (Debian, with gcc) for build, distroless/base (with glibc) for runtime.
• Vendoring detected: adds -mod=vendor and copies vendor/.
• System packages: dependencies declared in internal/knowledge/packages.yaml (e.g., go-sqlite3 → libsqlite3-dev).

Every non-trivial decision is recorded in .lbd-report.md with rationale and alternatives considered.

Scope

The MVP supports Go only. Node.js and Python are prepared for in the architecture via the Analyzer interface but are not implemented.

See docs/MVP.md for the full problem statement, motivation, and definition of done.

Development

make build       # binary at ./lbd
make test        # go test ./...
make lint        # go vet ./...

See CONTRIBUTING.md for details.

License

MIT — see LICENSE.