dockerfile-smells SKILL.md skillA
dockerfile-smells from sigistry/marketplace is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add sigistry/marketplace/dockerfile-smells@git:20260826.571bc2fPins git:20260826.571bc2f in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- sigistry/marketplace
- Path
plugins/ci-incident-medic/skills/dockerfile-smells/SKILL.md- Versions recorded
- 3
- Latest version
- git:20260826.571bc2f, committed Aug 26, 2026
- First version recorded
- Jul 8, 2026
- Size
- 3,428 bytes
- Repository stars
- 3
- License
- MIT
This skill should be used when the user mentions "Dockerfile", "docker image size", "container security", "multi-stage build", "distroless", "run as root", "docker layer caching", or is reviewing/optimizing a container image. It provides a catalog of Dockerfile anti-patterns and the hardening principles that fix them.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Dockerfile Smells and Hardening ## Purpose A consistent set of Dockerfile anti-patterns and their fixes, so container reviews produce smaller, safer, cache-friendly images the same way every time. This is container-build domain knowledge, the specific smells and the reasons they matter, not generic Docker syntax. ## Smell catalog | Smell | Why it hurts | Fix | |-------|--------------|-----| | Runs as `root` (no `USER`) | container escape = host root; violates PSS/most policies | add `USER <uid>` (numeric, non-root) | | `latest` / unpinned base tag | non-reproducible; silent base drift; supply-chain risk | pin `FROM img@sha256:<digest>` | | Single-stage build | ships compilers, headers, build deps in runtime image | multi-stage: build → slim runtime | | `COPY . .` before dep install | any source edit busts the dependency cache layer | copy manifests, install, *then* copy source | | Secrets baked in a layer | recoverable from image history forever | `RUN --mount=type=secret`; never `ENV TOKEN=` | | `apt-get` with no cleanup | apt lists/caches bloat the layer | `--no-install-recommends` + `rm -rf /var/lib/apt/lists/*` in the same `RUN` | …
Read the whole file at its exact version.
How to install
mdr add sigistry/marketplace/dockerfile-smells@sha256:f73db594f75709deThe line at the top of this page pins the label git:20260826.571bc2f, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_uob66ucnofnvmn7u)
4 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 3 versions of this file, between Jul 8, 2026 and Aug 26, 2026, about one every 24 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260826.571bc2f latest | 2026-08-26 | 571bc2f | 3,428 B | A | view · diff |
| git:20260715.fcd8714 | 2026-07-15 | fcd8714 | 3,442 B | A | view · diff |
| git:20260708.c0884a9 | 2026-07-08 | c0884a9 | 3,469 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (3428 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
sigistry/marketplace · 3 stars · license MIT · pushed 2026-10-30 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_uob66ucnofnvmn7u GET https://markdownregistry.com/api/v1/resolve?ref=sigistry/marketplace/dockerfile-smells GET https://markdownregistry.com/api/v1/blob/f73db594f75709de7186416f7756c674e6a17cbbd56957066d9e68f645688695
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.