compose-lint

Projects that follow the best practices below can voluntarily self-certify and show that they've achieved an Open Source Security Foundation (OpenSSF) best practices badge.

There is no set of practices that can guarantee that software will never have defects or vulnerabilities; even formal methods can fail if the specifications or assumptions are wrong. Nor is there any set of practices that can guarantee that a project will sustain a healthy and well-functioning development community. However, following best practices can help improve the results of projects. For example, some practices enable multi-person review before release, which can both help find otherwise hard-to-find technical vulnerabilities and help build trust and a desire for repeated interaction among developers from different companies. To earn a badge, all MUST and MUST NOT criteria must be met, all SHOULD criteria must be met OR be unmet with justification, and all SUGGESTED criteria must be met OR unmet (we want them considered at least). If you want to enter justification text as a generic comment, instead of being a rationale that the situation is acceptable, start the text block with '//' followed by a space. Feedback is welcome via the GitHub site as issues or pull requests There is also a mailing list for general discussion.

We gladly provide the information in several locales, however, if there is any conflict or inconsistency between the translations, the English version is the authoritative version.
If this is your project, please show your badge status on your project page! The badge status looks like this: Badge level for project 12472 is silver Here is how to embed it:
You can show your badge status by embedding this in your markdown file:
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or by embedding this in your HTML:
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These are the Silver level criteria. You can also view the Passing or Gold level criteria.

Baseline Series: Baseline Level 1 Baseline Level 2 Baseline Level 3

        

 Basics 17/17 ●

  • General

    Note that other projects may use the same name.

    compose-lint is a security-focused linter for Docker Compose files. It catches dangerous misconfigurations — exposed Docker sockets, privileged containers, missing capability restrictions, unpinned images, and more — before they reach production. Rules are grounded in the OWASP Docker Security Cheat Sheet and CIS Docker Benchmark, with every finding including specific, actionable fix guidance. Distributed on PyPI and Docker Hub; runs locally, in CI, or as a pre-commit hook.

    Please use SPDX license expression format; examples include "Apache-2.0", "BSD-2-Clause", "BSD-3-Clause", "GPL-2.0+", "LGPL-3.0+", "MIT", and "(BSD-2-Clause OR Ruby)". Do not include single quotes or double quotes.
    If there is more than one language, list them as comma-separated values (spaces optional) and sort them from most to least used. If there is a long list, please list at least the first three most common ones. If there is no language (e.g., this is a documentation-only or test-only project), use the single character "-". Please use a conventional capitalization for each language, e.g., "JavaScript".
    The Common Platform Enumeration (CPE) is a structured naming scheme for information technology systems, software, and packages. It is used in a number of systems and databases when reporting vulnerabilities.

    Single-maintainer project, intentionally narrow in scope: a security linter for Docker Compose files with PyYAML as the only runtime dependency. Supply-chain posture above typical: PyPI Trusted Publishing (OIDC, no long-lived tokens), Sigstore build attestations on every release, signed commits and tags (SSH), SHA-pinned GitHub Actions, hash-pinned CI lockfiles, and a merge-blocking ci-ok aggregate check. Continuous scanning via CodeQL, OpenSSF Scorecard, and ClusterFuzzLite. All changes flow through PRs with squash-merge and linear history on main. No cryptography is implemented; no binary artifacts are tracked.

  • Prerequisites


    Enough for a badge!

    The project MUST achieve a passing level badge. [achieve_passing]

  • Basic project website content


    Enough for a badge!

    The information on how to contribute MUST include the requirements for acceptable contributions (e.g., a reference to any required coding standard). (URL required) [contribution_requirements]

    https://github.com/tmatens/compose-lint?tab=contributing-ov-file#code-standards


  • Project oversight


    Enough for a badge!

    The project SHOULD have a legal mechanism where all developers of non-trivial amounts of project software assert that they are legally authorized to make these contributions. The most common and easily-implemented approach for doing this is by using a Developer Certificate of Origin (DCO), where users add "signed-off-by" in their commits and the project links to the DCO website. However, this MAY be implemented as a Contributor License Agreement (CLA), or other legal mechanism. (URL required) [dco]
    The DCO is the recommended mechanism because it's easy to implement, tracked in the source code, and git directly supports a "signed-off" feature using "commit -s". To be most effective it is best if the project documentation explains what "signed-off" means for that project. A CLA is a legal agreement that defines the terms under which intellectual works have been licensed to an organization or project. A contributor assignment agreement (CAA) is a legal agreement that transfers rights in an intellectual work to another party; projects are not required to have CAAs, since having CAA increases the risk that potential contributors will not contribute, especially if the receiver is a for-profit organization. The Apache Software Foundation CLAs (the individual contributor license and the corporate CLA) are examples of CLAs, for projects which determine that the risks of these kinds of CLAs to the project are less than their benefits.

    All non-bot commits must carry a Signed-off-by: trailer matching the commit author identity, certifying the Developer Certificate of Origin (https://developercertificate.org). A required CI job (Developer Certificate of Origin in .github/workflows/ci.yml) scans every commit in a PR and blocks merge if any non-bot commit lacks the trailer. Dependabot, Renovate, github-actions, and Mend bot commits are allow-listed. Policy documented in CONTRIBUTING.md: https://github.com/tmatens/compose-lint/blob/main/CONTRIBUTING.md#developer-certificate-of-origin [osps_le_01_01]


    Enough for a badge!

    The project MUST clearly define and document its project governance model (the way it makes decisions, including key roles). (URL required) [governance]
    There needs to be some well-established documented way to make decisions and resolve disputes. In small projects, this may be as simple as "the project owner and lead makes all final decisions". There are various governance models, including benevolent dictator and formal meritocracy; for more details, see Governance models. Both centralized (e.g., single-maintainer) and decentralized (e.g., group maintainers) approaches have been successfully used in projects. The governance information does not need to document the possibility of creating a project fork, since that is always possible for FLOSS projects.

    URL: https://github.com/tmatens/compose-lint/blob/main/GOVERNANCE.md

    Justification: GOVERNANCE.md at the repo root documents the project's decision-making model end-to-end: a single maintainer role (with the bus factor honestly stated as 1), lazy-consensus decision rule with explicit reasonable-window guidance per change class, branch-protection rule that no change reaches main outside a PR (including the maintainer's), procedure for adding and removing maintainers, appeal procedure, and code-of-conduct enforcement chain. Cross-links to MAINTAINERS.md (canonical roster) and docs/CONTINUITY.md (access continuity).


    Enough for a badge!

    The project MUST adopt a code of conduct and post it in a standard location. (URL required) [code_of_conduct]
    Projects may be able to improve the civility of their community and to set expectations about acceptable conduct by adopting a code of conduct. This can help avoid problems before they occur and make the project a more welcoming place to encourage contributions. This should focus only on behavior within the community/workplace of the project. Example codes of conduct are the Linux kernel code of conduct, the Contributor Covenant Code of Conduct, the Debian Code of Conduct, the Ubuntu Code of Conduct, the Fedora Code of Conduct, the GNOME Code Of Conduct, the KDE Community Code of Conduct, the Python Community Code of Conduct, The Ruby Community Conduct Guideline, and The Rust Code of Conduct.

    URL: https://github.com/tmatens/compose-lint/blob/main/.github/CODE_OF_CONDUCT.md

    Justification: The project adopts the Contributor Covenant v2.1, posted at the standard .github/CODE_OF_CONDUCT.md location that GitHub recognizes for the "Community Standards" panel. CONTRIBUTING.md links to it from the §"Maintainers" section.


    Enough for a badge!

    The project MUST clearly define and publicly document the key roles in the project and their responsibilities, including any tasks those roles must perform. It MUST be clear who has which role(s), though this might not be documented in the same way. (URL required) [roles_responsibilities]
    The documentation for governance and roles and responsibilities may be in one place.

    CONTRIBUTING.md "Maintainers" section lists the single project maintainer (@tmatens) with repository admin, release, and security-response responsibilities. See https://github.com/tmatens/compose-lint/blob/main/CONTRIBUTING.md#maintainers [osps_gv_01_02]


    Enough for a badge!

    The project MUST be able to continue with minimal interruption if any one person dies, is incapacitated, or is otherwise unable or unwilling to continue support of the project. In particular, the project MUST be able to create and close issues, accept proposed changes, and release versions of software, within a week of confirmation of the loss of support from any one individual. This MAY be done by ensuring someone else has any necessary keys, passwords, and legal rights to continue the project. Individuals who run a FLOSS project MAY do this by providing keys in a lockbox and a will providing any needed legal rights (e.g., for DNS names). (URL required) [access_continuity]

    URL: https://github.com/tmatens/compose-lint/blob/main/docs/CONTINUITY.md

    Justification: docs/CONTINUITY.md explicitly addresses the single-maintainer reality. The "short version" states that anyone can continue compose-lint by forking under the MIT license: hash-pinned requirements*.lock files, digest-pinned Docker base images, signed annotated tags, and the documented release process in docs/RELEASING.md are deliberately structured so a successor needs no private state from the original maintainer. The document then gives a per-asset access table (GitHub repo and Environments, PyPI Trusted Publisher binding, Docker Hub org composelint, repo secrets, signing keys) with recovery paths for each, plus a co-maintainer onboarding checklist and an honest "why bus factor is currently 1" section.


    Barely enough for a badge.

    The project SHOULD have a "bus factor" of 2 or more. (URL required) [bus_factor]
    A "bus factor" (aka "truck factor") is the minimum number of project members that have to suddenly disappear from a project ("hit by a bus") before the project stalls due to lack of knowledgeable or competent personnel. The truck-factor tool can estimate this for projects on GitHub. For more information, see Assessing the Bus Factor of Git Repositories by Cosentino et al.

    URL: https://github.com/tmatens/compose-lint/blob/main/docs/CONTINUITY.md

    Justification: Bus factor is 1. Acknowledged honestly in GOVERNANCE.md §Roles ("The bus factor is 1; we are honest about that."). Mitigated in docs/CONTINUITY.md, which documents reproducible-build provenance (hash-pinned lockfiles, digest-pinned base images, Sigstore attestations on every release), the fork path under the MIT license, and per-asset recovery procedures (GitHub repo and Environments, PyPI Trusted Publisher binding, Docker Hub org, signing keys) so the project can continue without the current maintainer's cooperation. The procedure to add a co-maintainer is defined in GOVERNANCE.md §"Adding a maintainer" and MAINTAINERS.md §"Adding or removing a maintainer".


  • Documentation


    Enough for a badge!

    The project MUST have a documented roadmap that describes what the project intends to do and not do for at least the next year. (URL required) [documentation_roadmap]
    The project might not achieve the roadmap, and that's fine; the purpose of the roadmap is to help potential users and contributors understand the intended direction of the project. It need not be detailed.

    URL: https://github.com/tmatens/compose-lint/blob/main/docs/ROADMAP.md

    Justification: docs/ROADMAP.md lays out milestones 1 (shipped v0.3) through 4 (v1.0 GA) with explicit deferred items (.deb/.rpm packages, see ADR-008) and gating prerequisites (e.g., the drift-check job that must land before the real-world examples library). Milestone 2.5 (Trust Surface + Install Polish) and Milestone 3 (Remediation: --fix UX) define the next twelve-plus months of intended work; the document also names what is explicitly out of scope and why, which is the harder half of a roadmap.


    Enough for a badge!

    The project MUST include documentation of the architecture (aka high-level design) of the software produced by the project. If the project does not produce software, select "not applicable" (N/A). (URL required) [documentation_architecture]
    A software architecture explains a program's fundamental structures, i.e., the program's major components, the relationships among them, and the key properties of these components and relationships.

    Architecture is documented in CLAUDE.md (Parser, Rules, Findings, Formatters, Engine components and their data flow) and supplemented by Architecture Decision Records in docs/adr/. Actors: end users running the CLI, rule authors, CI systems consuming SARIF. Actions: compose file loading, rule evaluation, finding emission, formatter selection. See https://github.com/tmatens/compose-lint/blob/main/CLAUDE.md#architecture [osps_sa_01_01]


    Enough for a badge!

    The project MUST document what the user can and cannot expect in terms of security from the software produced by the project (its "security requirements"). (URL required) [documentation_security]
    These are the security requirements that the software is intended to meet.

    URL:https://github.com/tmatens/compose-lint/blob/main/docs/SECURITY-EXPECTATIONS.md
    docs/SECURITY-EXPECTATIONS.md (137 lines) is the user-facing "what compose-lint will and will not do" document:

    Promises: no execution of YAML contents (SafeLoader only, no eval/exec/subprocess against parsed values); no network I/O (verifiable under --network none); no mutation of inputs (read-only).
    Non-promises: not a Compose schema validator; not a runtime/image scanner; not exhaustive (rules cover known patterns from OWASP/CIS/Docker docs).
    How to verify each claim (concrete commands).
    .github/SECURITY.md header now links to docs/ASSURANCE.md and docs/SECURITY-EXPECTATIONS.md. The trio of SECURITY.md (vuln-reporting policy) + ASSURANCE.md (formal assurance case) + SECURITY-EXPECTATIONS.md (user-facing promises) covers the criterion comprehensively.


    Enough for a badge!

    The project MUST provide a "quick start" guide for new users to help them quickly do something with the software. (URL required) [documentation_quick_start]
    The idea is to show users how to get started and make the software do anything at all. This is critically important for potential users to get started.

    URL: https://github.com/tmatens/compose-lint/blob/main/docs/SECURITY-EXPECTATIONS.md

    Justification: docs/SECURITY-EXPECTATIONS.md is the user-facing "what compose-lint will and will not do in security terms" document. It enumerates explicit promises (will not execute YAML contents — SafeLoader only, no eval/exec/subprocess against parsed values; will not connect to the network — verifiable under --network none; will not modify your Compose files — read-only) and explicit non-promises (not a Compose schema validator, not an image/runtime scanner, not exhaustive — rules cover known patterns from OWASP/CIS/Docker docs), with concrete commands to verify each claim. The trio of .github/SECURITY.md (vuln-reporting policy) + docs/ASSURANCE.md (formal assurance case) + docs/SECURITY-EXPECTATIONS.md (user-facing promises) is cross-linked from the SECURITY.md header.


    Enough for a badge!

    The project MUST make an effort to keep the documentation consistent with the current version of the project results (including software produced by the project). Any known documentation defects making it inconsistent MUST be fixed. If the documentation is generally current, but erroneously includes some older information that is no longer true, just treat that as a defect, then track and fix as usual. [documentation_current]
    The documentation MAY include information about differences or changes between versions of the software and/or link to older versions of the documentation. The intent of this criterion is that an effort is made to keep the documentation consistent, not that the documentation must be perfect.

    URL: https://github.com/tmatens/compose-lint/blob/main/.github/workflows/ci.yml

    Justification: Documentation currency is enforced by CI rather than by convention. The version-consistency job in ci.yml asserts that pyproject.toml and src/compose_lint/init.py declare the same version. The changelog-gate job asserts that CHANGELOG.md has a section for the version being released. docs/RELEASING.md lists every documentation surface (README copy-paste pins, action SHA pins, marketplace pin, CHANGELOG) that must move with a release; recent merge history (commits 4473fd3, 447c416, 23da963) shows those pins bumped in lockstep with each release.


    Enough for a badge!

    The project repository front page and/or website MUST identify and hyperlink to any achievements, including this best practices badge, within 48 hours of public recognition that the achievement has been attained. (URL required) [documentation_achievements]
    An achievement is any set of external criteria that the project has specifically worked to meet, including some badges. This information does not need to be on the project website front page. A project using GitHub can put achievements on the repository front page by adding them to the README file.

    URL: https://github.com/tmatens/compose-lint#compose-lint

    Justification: The README header carries badges that hyperlink to every active achievement: CI status, PyPI version, Docker Hub presence, supported Python versions, MIT license, OpenSSF Scorecard, OpenSSF Best Practices Baseline level 2, and the OpenSSF Best Practices badge for this project (12472). Each badge links to the source of truth (the corresponding GitHub Actions workflow, the PyPI page, the Scorecard viewer, or the bestpractices.dev project page).


  • Accessibility and internationalization


    Enough for a badge!

    The project (both project sites and project results) SHOULD follow accessibility best practices so that persons with disabilities can still participate in the project and use the project results where it is reasonable to do so. [accessibility_best_practices]
    For web applications, see the Web Content Accessibility Guidelines (WCAG 2.0) and its supporting document Understanding WCAG 2.0; see also W3C accessibility information. For GUI applications, consider using the environment-specific accessibility guidelines (such as Gnome, KDE, XFCE, Android, iOS, Mac, and Windows). Some TUI applications (e.g. `ncurses` programs) can do certain things to make themselves more accessible (such as `alpine`'s `force-arrow-cursor` setting). Most command-line applications are fairly accessible as-is. This criterion is often N/A, e.g., for program libraries. Here are some examples of actions to take or issues to consider:
    • Provide text alternatives for any non-text content so that it can be changed into other forms people need, such as large print, braille, speech, symbols or simpler language ( WCAG 2.0 guideline 1.1)
    • Color is not used as the only visual means of conveying information, indicating an action, prompting a response, or distinguishing a visual element. ( WCAG 2.0 guideline 1.4.1)
    • The visual presentation of text and images of text has a contrast ratio of at least 4.5:1, except for large text, incidental text, and logotypes ( WCAG 2.0 guideline 1.4.3)
    • Make all functionality available from a keyboard (WCAG guideline 2.1)
    • A GUI or web-based project SHOULD test with at least one screen-reader on the target platform(s) (e.g. NVDA, Jaws, or WindowEyes on Windows; VoiceOver on Mac & iOS; Orca on Linux/BSD; TalkBack on Android). TUI programs MAY work to reduce overdraw to prevent redundant reading by screen-readers.

    Justification: compose-lint is a command-line tool with no GUI, no web frontend, and no user-facing visual interface. Output is plain ASCII text (text mode), JSON (machine-readable), or SARIF (consumable by GitHub Code Scanning, which carries its own accessibility testing). The CLI emits ANSI color only when stdout is detected as a TTY (auto-disables when piped or redirected), so screen-reader users never receive escape sequences. There is no accessibility surface to test against and no FLOSS accessibility-best-practices framework that applies.


    Enough for a badge!

    The software produced by the project SHOULD be internationalized to enable easy localization for the target audience's culture, region, or language. If internationalization (i18n) does not apply (e.g., the software doesn't generate text intended for end-users and doesn't sort human-readable text), select "not applicable" (N/A). [internationalization]
    Localization "refers to the adaptation of a product, application or document content to meet the language, cultural and other requirements of a specific target market (a locale)." Internationalization is the "design and development of a product, application or document content that enables easy localization for target audiences that vary in culture, region, or language." (See W3C's "Localization vs. Internationalization".) Software meets this criterion simply by being internationalized. No localization for another specific language is required, since once software has been internationalized it's possible for others to work on localization.

    Justification: compose-lint targets developers reading technical findings whose authoritative grounding (OWASP Docker Security Cheat Sheet, CIS Docker Benchmark, Docker official documentation) is published exclusively in English. Localizing rule descriptions, fix guidance, and the references they cite would require translating the upstream sources, which is out of project scope. The tool emits no end-user-facing prose beyond rule findings.


  • Other


    Enough for a badge!

    If the project sites (website, repository, and download URLs) store passwords for authentication of external users, the passwords MUST be stored as iterated hashes with a per-user salt by using a key stretching (iterated) algorithm (e.g., Argon2id, Bcrypt, Scrypt, or PBKDF2). If the project sites do not store passwords for this purpose, select "not applicable" (N/A). [sites_password_security]
    Note that the use of GitHub meets this criterion. This criterion only applies to passwords used for authentication of external users into the project sites (aka inbound authentication). If the project sites must log in to other sites (aka outbound authentication), they may need to store authorization tokens for that purpose differently (since storing a hash would be useless). This applies criterion crypto_password_storage to the project sites, similar to sites_https.

    Justification: The project hosts no sites that store user passwords. Project presence is GitHub (https://github.com/tmatens/compose-lint), PyPI (https://pypi.org/project/compose-lint/), and Docker Hub (https://hub.docker.com/r/composelint/compose-lint) — every authentication surface is delegated to those parent platforms.


 Change Control 1/1 ●

  • Previous versions


    Enough for a badge!

    The project MUST maintain the most often used older versions of the product or provide an upgrade path to newer versions. If the upgrade path is difficult, the project MUST document how to perform the upgrade (e.g., the interfaces that have changed and detailed suggested steps to help upgrade). [maintenance_or_update]

    URL: https://github.com/tmatens/compose-lint/blob/main/.github/SECURITY.md#supported-versions

    Justification: .github/SECURITY.md §"Supported Versions" states: "Only the latest minor release receives security fixes." Pre-1.0 SemVer rules are documented in docs/RELEASING.md (PATCH = bug fixes only; MINOR = additive changes plus new rules at non-CRITICAL severity; MAJOR = breaking changes). The upgrade path is pip install --upgrade compose-lint (PyPI) or pulling the new tag from composelint/compose-lint (Docker Hub). Every release ships a CHANGELOG entry calling out anything that changes findings (rule additions, severity adjustments, parser fixes), so users can plan upgrades against a stable contract.


 Reporting 3/3 ●

  • Bug-reporting process


    Enough for a badge!

    The project MUST use an issue tracker for tracking individual issues. [report_tracker]

    The project uses GitHub Issues as its public issue tracker for bug reports and feature requests. The tracker is linked from README.md, CONTRIBUTING.md, and the PyPI project page.


  • Vulnerability report process


    Enough for a badge!

    The project MUST give credit to the reporter(s) of all vulnerability reports resolved in the last 12 months, except for the reporter(s) who request anonymity. If there have been no vulnerabilities resolved in the last 12 months, select "not applicable" (N/A). (URL required) [vulnerability_report_credit]

    URL: https://github.com/tmatens/compose-lint/blob/main/.github/SECURITY.md

    Justification: .github/SECURITY.md documents the process end-to-end. Reports are filed privately via GitHub Security Advisories at https://github.com/tmatens/compose-lint/security/advisories/new (public issues are explicitly disallowed for vulnerabilities). The maintainer commits to a 7-day acknowledgement SLA, then fix coordination and advisory publication with credit. Scope (in-scope: code execution / info disclosure via crafted Compose, supply-chain tampering, exploitable vulnerable dependencies; out-of-scope: rule false positives/negatives, vulnerable test fixtures) is defined explicitly. CONTRIBUTING.md §"Maintainers" reaffirms the 7-day security-ack SLA.


    Enough for a badge!

    The project MUST have a documented process for responding to vulnerability reports. (URL required) [vulnerability_response_process]
    This is strongly related to vulnerability_report_process, which requires that there be a documented way to report vulnerabilities. It also related to vulnerability_report_response, which requires response to vulnerability reports within a certain time frame.

    SECURITY.md documents the CVD process: private reporting via GitHub Security Advisories, acknowledgement within 7 days, coordinated fix and advisory publication with credit. See https://github.com/tmatens/compose-lint/blob/main/SECURITY.md [osps_vm_01_01]


 Quality 19/19 ●

  • Coding standards


    Enough for a badge!

    The project MUST identify the specific coding style guides for the primary languages it uses, and require that contributions generally comply with it. (URL required) [coding_standards]
    In most cases this is done by referring to some existing style guide(s), possibly listing differences. These style guides can include ways to improve readability and ways to reduce the likelihood of defects (including vulnerabilities). Many programming languages have one or more widely-used style guides. Examples of style guides include Google's style guides and SEI CERT Coding Standards.

    URL: https://github.com/tmatens/compose-lint/blob/main/pyproject.toml

    Justification: The primary language is Python 3.10+. pyproject.toml [tool.ruff.lint] selects the active rule families: PEP 8 (E, W), pyflakes (F), isort (I), pyupgrade (UP), bugbear (B), simplify (SIM), and flake8-type-checking (TCH). pyproject.toml [tool.mypy] sets strict = true. target-version = "py310". Formatting is ruff format (Black-compatible). CONTRIBUTING.md §"Code standards" enumerates the additional contributor-facing rules (Python 3.10+ stdlib only, type annotations on all public functions, plain Python types in rule code, latest stable for new dependencies).


    Enough for a badge!

    The project MUST automatically enforce its selected coding style(s) if there is at least one FLOSS tool that can do so in the selected language(s). [coding_standards_enforced]
    This MAY be implemented using static analysis tool(s) and/or by forcing the code through code reformatters. In many cases the tool configuration is included in the project's repository (since different projects may choose different configurations). Projects MAY allow style exceptions (and typically will); where exceptions occur, they MUST be rare and documented in the code at their locations, so that these exceptions can be reviewed and so that tools can automatically handle them in the future. Examples of such tools include ESLint (JavaScript), Rubocop (Ruby), and devtools check (R).

    URL: https://github.com/tmatens/compose-lint/blob/main/.github/workflows/ci.yml

    Justification: Every standard above is enforced by CI on every push and pull request to main:

    lint job: ruff check src/ tests/ and ruff format --check src/ tests/.
    type-check job: mypy src/ (strict).
    test matrix: pytest on Python 3.10, 3.11, 3.12, 3.13, 3.14.
    coverage job: pytest --cov=compose_lint --cov-fail-under=80. Locally, the pre-push hook in .githooks/ blocks unsigned commits before they reach origin. Required-status-checks on main block merges if any CI gate fails.


  • Working build system


    Enough for a badge!

    Build systems for native binaries MUST honor the relevant compiler and linker (environment) variables passed in to them (e.g., CC, CFLAGS, CXX, CXXFLAGS, and LDFLAGS) and pass them to compiler and linker invocations. A build system MAY extend them with additional flags; it MUST NOT simply replace provided values with its own. If no native binaries are being generated, select "not applicable" (N/A). [build_standard_variables]
    It should be easy to enable special build features like Address Sanitizer (ASAN), or to comply with distribution hardening best practices (e.g., by easily turning on compiler flags to do so).

    Justification: compose-lint is pure Python; no native binaries are built. The Hatchling build backend produces a py3-none-any wheel. There are no compiler or linker invocations to honor CC/CFLAGS/etc.


    Enough for a badge!

    The build and installation system SHOULD preserve debugging information if they are requested in the relevant flags (e.g., "install -s" is not used). If there is no build or installation system (e.g., typical JavaScript libraries), select "not applicable" (N/A). [build_preserve_debug]
    E.G., setting CFLAGS (C) or CXXFLAGS (C++) should create the relevant debugging information if those languages are used, and they should not be stripped during installation. Debugging information is needed for support and analysis, and also useful for measuring the presence of hardening features in the compiled binaries.

    Justification: There is no compiler/linker step. Python source ships verbatim inside the wheel, so debugging information (source line numbers, identifiers) is inherently preserved.


    Enough for a badge!

    The build system for the software produced by the project MUST NOT recursively build subdirectories if there are cross-dependencies in the subdirectories. If there is no build or installation system (e.g., typical JavaScript libraries), select "not applicable" (N/A). [build_non_recursive]
    The project build system's internal dependency information needs to be accurate, otherwise, changes to the project may not build correctly. Incorrect builds can lead to defects (including vulnerabilities). A common mistake in large build systems is to use a "recursive build" or "recursive make", that is, a hierarchy of subdirectories containing source files, where each subdirectory is independently built. Unless each subdirectory is fully independent, this is a mistake, because the dependency information is incorrect.

    Justification: Hatchling traverses a single source tree (src/compose_lint/) to produce the wheel. There is no recursive Make, no sub-builds, and therefore no cross-dependency hazard.


    Enough for a badge!

    The project MUST be able to repeat the process of generating information from source files and get exactly the same bit-for-bit result. If no building occurs (e.g., scripting languages where the source code is used directly instead of being compiled), select "not applicable" (N/A). [build_repeatable]
    GCC and clang users may find the -frandom-seed option useful; in some cases, this can be resolved by forcing some sort order. More suggestions can be found at the reproducible build site.

    URL: https://github.com/tmatens/compose-lint/blob/main/docs/RELEASING.md

    Justification:

    Hatchling produces deterministic wheels (declared input file lists, sorted output).
    PyPI publishes happen via Trusted Publishing (OIDC) with Sigstore build attestations attached to every release — anyone can independently verify provenance.
    Every CI install uses pip install --require-hashes -r requirements.lock (or requirements-dev.lock / requirements-build.lock); the lockfiles are regenerated reproducibly using the documented uv pip compile --generate-hashes invocations in AGENTS.md §"Regenerating lockfiles".
    Every GitHub Actions uses: reference is SHA-pinned with the tag in a trailing comment (Renovate manages the bumps).
    Docker base image is digest-pinned to the OCI manifest-list digest.


  • Installation system


    Enough for a badge!

    The project MUST provide a way to easily install and uninstall the software produced by the project using a commonly-used convention. [installation_common]
    Examples include using a package manager (at the system or language level), "make install/uninstall" (supporting DESTDIR), a container in a standard format, or a virtual machine image in a standard format. The installation and uninstallation process (e.g., its packaging) MAY be implemented by a third party as long as it is FLOSS.

    URL: https://github.com/tmatens/compose-lint#installation

    Justification: README.md §"Installation" documents multiple install paths, all using widely-recognized conventions:

    pip install compose-lint (uninstall: pip uninstall compose-lint).
    docker run --rm -v "$(pwd):/src" composelint/compose-lint (the published image is multi-arch, distroless, nonroot).
    pre-commit hook (.pre-commit-hooks.yaml exposes the compose-lint ID for repos: use).
    GitHub Action (uses: tmatens/compose-lint@v0.7.0).


    Enough for a badge!

    The installation system for end-users MUST honor standard conventions for selecting the location where built artifacts are written to at installation time. For example, if it installs files on a POSIX system it MUST honor the DESTDIR environment variable. If there is no installation system or no standard convention, select "not applicable" (N/A). [installation_standard_variables]

    URL: https://github.com/tmatens/compose-lint/blob/main/pyproject.toml

    Justification: pip honors PEP 517 / PEP 668 conventions for install location (system, virtual environment, --user, pipx). The [project.scripts] entry in pyproject.toml — compose-lint = "compose_lint.cli:main" — installs the launcher to the standard bin/ of whatever environment pip is operating against. There is no custom prefix logic, no out-of-tree install hooks, no override of the standard build/install backend.


    Enough for a badge!

    The project MUST provide a way for potential developers to quickly install all the project results and support environment necessary to make changes, including the tests and test environment. This MUST be performed with a commonly-used convention. [installation_development_quick]
    This MAY be implemented using a generated container and/or installation script(s). External dependencies would typically be installed by invoking system and/or language package manager(s), per external_dependencies.

    CONTRIBUTING.md "Development setup" documents the full build procedure (Python ≥3.10, virtualenv, editable install with dev extras). pyproject.toml declares build-system requirements. See https://github.com/tmatens/compose-lint/blob/main/CONTRIBUTING.md#development-setup [osps_do_07_01]


  • Externally-maintained components


    Enough for a badge!

    The project MUST list external dependencies in a computer-processable way. (URL required) [external_dependencies]
    Typically this is done using the conventions of package manager and/or build system. Note that this helps implement installation_development_quick.

    Dependencies are ingested via pip with hash-pinned lockfiles (requirements.lock, requirements-dev.lock, requirements-build.lock) generated by uv pip compile. CI installs use pip install --require-hashes. GitHub Actions are SHA-pinned. See https://github.com/tmatens/compose-lint/blob/main/CLAUDE.md#dependency-pinning [osps_br_05_01]


    Enough for a badge!

    Projects MUST monitor or periodically check their external dependencies (including convenience copies) to detect known vulnerabilities, and fix exploitable vulnerabilities or verify them as unexploitable. [dependency_monitoring]
    This can be done using an origin analyzer / dependency checking tool / software composition analysis tool such as OWASP's Dependency-Check, Sonatype's Nexus Auditor, Synopsys' Black Duck Software Composition Analysis, and Bundler-audit (for Ruby). Some package managers include mechanisms to do this. It is acceptable if the components' vulnerability cannot be exploited, but this analysis is difficult and it is sometimes easier to simply update or fix the part.

    URL: https://github.com/tmatens/compose-lint/tree/main/.github/workflows

    Justification: Multiple layers of dependency monitoring run continuously:

    Renovate (.github/renovate.json) opens dep-bump PRs weekly across runtime deps, dev tooling, GitHub Actions SHA pins, and Docker base image digests.
    pip-audit runs in the security job of ci.yml on every push and PR (reports all severities; gating reserved for critical).
    Bandit runs in the same job for Python source-level vulnerability patterns.
    CodeQL (.github/workflows/codeql.yml) runs on every push/PR and weekly on schedule.
    OpenSSF Scorecard (.github/workflows/scorecard.yml) runs weekly and publishes SARIF.
    Docker Scout (.github/workflows/scout-scan.yml) scans the published image; .vex/ ships OpenVEX statements for downstream consumers.
    ClusterFuzzLite (.clusterfuzzlite/, fuzz/fuzz_compose.py) fuzzes the parser on every PR.


    Enough for a badge!

    The project MUST either:
    1. make it easy to identify and update reused externally-maintained components; or
    2. use the standard components provided by the system or programming language.
    Then, if a vulnerability is found in a reused component, it will be easy to update that component. [updateable_reused_components]
    A typical way to meet this criterion is to use system and programming language package management systems. Many FLOSS programs are distributed with "convenience libraries" that are local copies of standard libraries (possibly forked). By itself, that's fine. However, if the program *must* use these local (forked) copies, then updating the "standard" libraries as a security update will leave these additional copies still vulnerable. This is especially an issue for cloud-based systems; if the cloud provider updates their "standard" libraries but the program won't use them, then the updates don't actually help. See, e.g., "Chromium: Why it isn't in Fedora yet as a proper package" by Tom Callaway.

    Direct Python dependencies are declared in pyproject.toml (dependencies and the [project.optional-dependencies] table). Fully-resolved hash-pinned lockfiles (requirements.lock, requirements-dev.lock, requirements-build.lock) are committed for reproducible CI installs. See https://github.com/tmatens/compose-lint/blob/main/pyproject.toml [osps_qa_02_01]


    Enough for a badge!

    The project SHOULD avoid using deprecated or obsolete functions and APIs where FLOSS alternatives are available in the set of technology it uses (its "technology stack") and to a supermajority of the users the project supports (so that users have ready access to the alternative). [interfaces_current]

    URL: https://github.com/tmatens/compose-lint/blob/main/pyproject.toml

    Justification:

    pyproject.toml sets target-version = "py310"; ruff's UP (pyupgrade) rules auto-flag deprecated stdlib idioms (e.g., typing.List → list).
    The CI test matrix runs Python 3.10 through 3.14, so any deprecation surfacing at the latest interpreter fails CI.
    The parser uses yaml.SafeLoader (the safe, current API), never the deprecated yaml.load(..., Loader=...) shape.
    mypy strict catches use of deprecated typing aliases that have moved.


  • Automated test suite


    Enough for a badge!

    An automated test suite MUST be applied on each check-in to a shared repository for at least one branch. This test suite MUST produce a report on test success or failure. [automated_integration_testing]
    This requirement can be viewed as a subset of test_continuous_integration, but focused on just testing, without requiring continuous integration.

    CI runs the full pytest suite across Python 3.10–3.14 on every PR via .github/workflows/ci.yml; the aggregate ci-ok check is required by the main branch ruleset, blocking merge unless tests pass. [osps_qa_06_01]


    Enough for a badge!

    The project MUST add regression tests to an automated test suite for at least 50% of the bugs fixed within the last six months. [regression_tests_added50]

    URL: https://github.com/tmatens/compose-lint/blob/main/CONTRIBUTING.md

    Justification: CONTRIBUTING.md §"PR expectations" mandates: "Update tests. New rules need positive and negative tests. Bug fixes need a regression test." Reviewer-enforced; the maintainer rejects bug-fix PRs that don't include the regression test in the same commit. The pull-request template surfaces this expectation at PR-creation time. Bug-fix commits in git log consistently land with their regression test in the same commit, comfortably exceeding the 50% threshold.


    Enough for a badge!

    The project MUST have FLOSS automated test suite(s) that provide at least 80% statement coverage if there is at least one FLOSS tool that can measure this criterion in the selected language. [test_statement_coverage80]
    Many FLOSS tools are available to measure test coverage, including gcov/lcov, Blanket.js, Istanbul, JCov, and covr (R). Note that meeting this criterion is not a guarantee that the test suite is thorough, instead, failing to meet this criterion is a strong indicator of a poor test suite.

    URL: https://github.com/tmatens/compose-lint/blob/main/.github/workflows/ci.yml

    Justification: Statement coverage is measured in CI on every push and PR and gated at ≥80%:

    pyproject.toml adds pytest-cov==7.1.0 to the [dev] extras and configures [tool.coverage.run] (source = compose_lint, statement coverage, parallel = true) plus [tool.coverage.report] (fail_under = 80, show_missing, sensible excludes for TYPE_CHECKING / NotImplementedError / # pragma: no cover).
    The coverage job in .github/workflows/ci.yml runs pytest --cov=compose_lint --cov-report=term-missing --cov-fail-under=80 on Python 3.13. The threshold is duplicated at the workflow level so a config drift cannot silently lower it. The job is in the ci-ok rollup so branch protection enforces it.
    A subprocess-coverage shim (coverage_subprocess.pth + COVERAGE_PROCESS_START) ensures coverage measures the python -m compose_lint subprocesses spawned by test_cli.py and test_integration.py. Measured statement coverage on Linux CI is approximately 93%.
    CONTRIBUTING.md §"Local quality checks" documents the local coverage command for contributors.


  • New functionality testing


    Enough for a badge!

    The project MUST have a formal written policy that as major new functionality is added, tests for the new functionality MUST be added to an automated test suite. [test_policy_mandated]

    URL: https://github.com/tmatens/compose-lint/blob/main/CONTRIBUTING.md

    Justification: CONTRIBUTING.md §"Adding a new rule" lists the test obligation as step 5 of the new-rule checklist: "Add test file tests/test_CL{NNNN}.py with both positive (triggers) and negative (clean) cases. Negative cases must include at least one hardened-but-unusual configuration the rule must not flag." §"PR expectations" generalizes the rule: tests required for new functionality, regression tests required for bug fixes. The PR template links back to CONTRIBUTING.md so contributors see the policy at PR-creation time.


    Enough for a badge!

    The project MUST include, in its documented instructions for change proposals, the policy that tests are to be added for major new functionality. [tests_documented_added]
    However, even an informal rule is acceptable as long as the tests are being added in practice.

    Documented in CONTRIBUTING.md §"Adding a new rule" (test file is step 5 of the checklist) and §"PR expectations" ("Update tests. New rules need positive and negative tests. Bug fixes need a regression test."). The PR template links back to CONTRIBUTING.md.


  • Warning flags


    Enough for a badge!

    Projects MUST be maximally strict with warnings in the software produced by the project, where practical. [warnings_strict]
    Some warnings cannot be effectively enabled on some projects. What is needed is evidence that the project is striving to enable warning flags where it can, so that errors are detected early.

    mypy runs with strict = true (the maximum setting: enables all optional strict flags). ruff selects broad rule families including B (bugbear correctness checks) and UP (pyupgrade modernization) in addition to the defaults. Formatting drift is also an error (ruff format --check).


 Security 13/13 ●

  • Secure development knowledge


    Enough for a badge!

    The project MUST implement secure design principles (from "know_secure_design"), where applicable. If the project is not producing software, select "not applicable" (N/A). [implement_secure_design]
    For example, the project results should have fail-safe defaults (access decisions should deny by default, and projects' installation should be secure by default). They should also have complete mediation (every access that might be limited must be checked for authority and be non-bypassable). Note that in some cases principles will conflict, in which case a choice must be made (e.g., many mechanisms can make things more complex, contravening "economy of mechanism" / keep it simple).

    Secure design principles applied throughout:

    Least privilege: single runtime dep (PyYAML); CI workflows declare permissions: {} deny-all and per-job least-privilege scopes; published Docker image is distroless, runs as nonroot uid 65532, drops all capabilities by documented invocation.
    Input validation: LineLoader(yaml.SafeLoader) — never yaml.load() — rejects malformed/unsafe YAML and Python-object tags. Engine validates that services: exists and is a mapping (ADR-013). Rules receive plain Python primitives; parser-specific types never leak into rule code.
    Fail-secure: usage errors and parse failures exit 2 (distinct from "findings present" exit 1). Default --fail-on=HIGH errs on the side of breaking the build.
    Defense in depth: mypy strict + ruff B (bugbear) + Bandit + CodeQL + ClusterFuzzLite fuzzing + pip-audit + Scorecard, layered.
    Secure defaults: pre-commit hook fails closed; GitHub Action runs without arguments and lints repository defaults; Docker image entrypoint is the linter (no shell).
    Supply-chain security: Trusted Publishing (no long-lived PyPI tokens), Sigstore attestations, hash-pinned lockfiles, SHA-pinned actions, signed git tags, OIDC for Docker Hub.
    References: README §"Security posture", SECURITY.md §"Supply Chain", docs/adr/003-yaml-parsing.md, docs/adr/006-exit-codes.md, docs/adr/009-runtime-base-image.md.


  • Use basic good cryptographic practices

    Note that some software does not need to use cryptographic mechanisms. If your project produces software that (1) includes, activates, or enables encryption functionality, and (2) might be released from the United States (US) to outside the US or to a non-US-citizen, you may be legally required to take a few extra steps. Typically this just involves sending an email. For more information, see the encryption section of Understanding Open Source Technology & US Export Controls.

    Enough for a badge!

    The default security mechanisms within the software produced by the project MUST NOT depend on cryptographic algorithms or modes with known serious weaknesses (e.g., the SHA-1 cryptographic hash algorithm or the CBC mode in SSH). [crypto_weaknesses]
    Concerns about CBC mode in SSH are discussed in CERT: SSH CBC vulnerability.

    N/A — compose-lint is a static Docker Compose linter. The software produced implements no cryptographic protocols, algorithms, password storage, or key/nonce generation. Sole runtime dependency is PyYAML.


    Enough for a badge!

    The project SHOULD support multiple cryptographic algorithms, so users can quickly switch if one is broken. Common symmetric key algorithms include AES, Twofish, and Serpent. Common cryptographic hash algorithm alternatives include SHA-2 (including SHA-224, SHA-256, SHA-384 AND SHA-512) and SHA-3. [crypto_algorithm_agility]

    compose-lint implements no cryptographic algorithms in its product code. PyYAML, the sole runtime dependency, performs no crypto. Mark N/A.


    Enough for a badge!

    The project MUST support storing authentication credentials (such as passwords and dynamic tokens) and private cryptographic keys in files that are separate from other information (such as configuration files, databases, and logs), and permit users to update and replace them without code recompilation. If the project never processes authentication credentials and private cryptographic keys, select "not applicable" (N/A). [crypto_credential_agility]

    compose-lint implements no cryptographic algorithms in its product code. PyYAML, the sole runtime dependency, performs no crypto. Mark N/A.


    Enough for a badge!

    The software produced by the project SHOULD support secure protocols for all of its network communications, such as SSHv2 or later, TLS1.2 or later (HTTPS), IPsec, SFTP, and SNMPv3. Insecure protocols such as FTP, HTTP, telnet, SSLv3 or earlier, and SSHv1 SHOULD be disabled by default, and only enabled if the user specifically configures it. If the software produced by the project does not support network communications, select "not applicable" (N/A). [crypto_used_network]

    compose-lint performs no network communication at runtime. The CLI reads files from disk and writes findings to stdout/stderr. Mark N/A.


    Enough for a badge!

    The software produced by the project SHOULD, if it supports or uses TLS, support at least TLS version 1.2. Note that the predecessor of TLS was called SSL. If the software does not use TLS, select "not applicable" (N/A). [crypto_tls12]

    No TLS use. Mark N/A.


    Enough for a badge!

    The software produced by the project MUST, if it supports TLS, perform TLS certificate verification by default when using TLS, including on subresources. If the software does not use TLS, select "not applicable" (N/A). [crypto_certificate_verification]
    Note that incorrect TLS certificate verification is a common mistake. For more information, see "The Most Dangerous Code in the World: Validating SSL Certificates in Non-Browser Software" by Martin Georgiev et al. and "Do you trust this application?" by Michael Catanzaro.

    No TLS use. Mark N/A.


    Enough for a badge!

    The software produced by the project MUST, if it supports TLS, perform certificate verification before sending HTTP headers with private information (such as secure cookies). If the software does not use TLS, select "not applicable" (N/A). [crypto_verification_private]

    No TLS use. Mark N/A.


  • Secure release


    Enough for a badge!

    The project MUST cryptographically sign releases of the project results intended for widespread use, and there MUST be a documented process explaining to users how they can obtain the public signing keys and verify the signature(s). The private key for these signature(s) MUST NOT be on site(s) used to directly distribute the software to the public. If releases are not intended for widespread use, select "not applicable" (N/A). [signed_releases]
    The project results include both source code and any generated deliverables where applicable (e.g., executables, packages, and containers). Generated deliverables MAY be signed separately from source code. These MAY be implemented as signed git tags (using cryptographic digital signatures). Projects MAY provide generated results separately from tools like git, but in those cases, the separate results MUST be separately signed.

    PyPI releases include Sigstore build attestations generated via Trusted Publishing (OIDC) — each wheel and sdist is accompanied by a signed attestation. Git tags are SSH-signed. Verify via PyPI's attestation viewer or python -m sigstore verify. See https://github.com/tmatens/compose-lint/blob/main/SECURITY.md [osps_br_06_01]


    Enough for a badge!

    It is SUGGESTED that in the version control system, each important version tag (a tag that is part of a major release, minor release, or fixes publicly noted vulnerabilities) be cryptographically signed and verifiable as described in signed_releases. [version_tags_signed]

    Every release tag is git tag -s SSH-signed annotated. publish.yml verify-tag job now performs three checks (the previously-noted "follow-up" is closed):

    Annotated tag (git cat-file -t returns tag, not commit).
    Reachable from origin/main.
    SSH signature verifies against .github/allowed_signers (added in PR #202; key namespace-scoped to git so it cannot be reused for arbitrary SSH signing if leaked). Pre-flight handles missing/empty allowed_signers with an explicit error pointing at the rotation procedure in GOVERNANCE.md.
    End-to-end provenance chain is now: SSH-verified annotated tag → reachable-from-main → CI build → Sigstore attestation → PyPI / Docker Hub.


  • Other security issues


    Enough for a badge!

    The project results MUST check all inputs from potentially untrusted sources to ensure they are valid (an *allowlist*), and reject invalid inputs, if there are any restrictions on the data at all. [input_validation]
    Note that comparing input against a list of "bad formats" (aka a *denylist*) is normally not enough, because attackers can often work around a denylist. In particular, numbers are converted into internal formats and then checked if they are between their minimum and maximum (inclusive), and text strings are checked to ensure that they are valid text patterns (e.g., valid UTF-8, length, syntax, etc.). Some data may need to be "anything at all" (e.g., a file uploader), but these would typically be rare.

    Parser: LineLoader(yaml.SafeLoader) rejects unsafe YAML constructs (Python-object tags, arbitrary class instantiation). Documented in ADR-003.
    Engine: validates that services: exists and is a mapping; emits a usage error (exit 2) otherwise. ADR-013 covers the missing-services-key handling.
    Rules: receive only plain Python primitives; rule code does not reach back to parser internals.
    Allowlist nature: rules check for known-bad patterns, not arbitrary input shapes; the allowlist for what counts as "valid Compose" is delegated to authoritative Compose schema (the linter is intentionally lenient on schema compliance to focus on security findings — see feedback_scope_security_not_style memory).
    Fuzzing: fuzz/fuzz_compose.py runs continuously via ClusterFuzzLite (.clusterfuzzlite/) on every PR, attacking the parser surface with adversarial input.


    Enough for a badge!

    Hardening mechanisms SHOULD be used in the software produced by the project so that software defects are less likely to result in security vulnerabilities. [hardening]
    Hardening mechanisms may include HTTP headers like Content Security Policy (CSP), compiler flags to mitigate attacks (such as -fstack-protector), or compiler flags to eliminate undefined behavior. For our purposes least privilege is not considered a hardening mechanism (least privilege is important, but separate).

    Memory-safe language: pure Python. Type system enforcement: mypy --strict in CI. Lint-level hardening: ruff B (bugbear correctness rules), UP (pyupgrade), SIM (simplify), TCH (type-checking) — all run on every PR. Runtime container hardening: published Docker image is distroless, multi-arch, nonroot (uid 65532); README documents the fully-hardened invocation (--read-only --cap-drop ALL --security-opt no-new-privileges:true --network none --user 65532:65532 --pids-limit 256). CI workflow hardening: every workflow declares permissions: {} deny-all at top; jobs request only the scopes they need; every uses: is SHA-pinned with a trailing tag comment. Supply-chain hardening: PyPI Trusted Publishing (no long-lived tokens), hash-pinned lockfiles, signed annotated tags, Sigstore attestations, cosign-signed Docker images.


    Enough for a badge!

    The project MUST provide an assurance case that justifies why its security requirements are met. The assurance case MUST include: a description of the threat model, clear identification of trust boundaries, an argument that secure design principles have been applied, and an argument that common implementation security weaknesses have been countered. (URL required) [assurance_case]
    An assurance case is "a documented body of evidence that provides a convincing and valid argument that a specified set of critical claims regarding a system’s properties are adequately justified for a given application in a given environment" ("Software Assurance Using Structured Assurance Case Models", Thomas Rhodes et al, NIST Interagency Report 7608). Trust boundaries are boundaries where data or execution changes its level of trust, e.g., a server's boundaries in a typical web application. It's common to list secure design principles (such as Saltzer and Schroeer) and common implementation security weaknesses (such as the OWASP top 10 or CWE/SANS top 25), and show how each are countered. The BadgeApp assurance case may be a useful example. This is related to documentation_security, documentation_architecture, and implement_secure_design.

    Threat surface assessed and documented across the project: SECURITY.md defines scope and out-of-scope; the architecture is deliberately minimal (PyYAML only runtime dependency, read-only file processing, no network, no eval); adversarial inputs (malformed YAML, billion-laughs-style attacks, crafted anchor/merge chains) are exercised by ClusterFuzzLite continuous fuzzing. Supply-chain surface hardened via Trusted Publishing, Sigstore attestations, signed commits/tags, SHA-pinned actions, hash-pinned lockfiles. See https://github.com/tmatens/compose-lint/blob/main/SECURITY.md [osps_sa_03_01]


 Analysis 2/2 ●

  • Static code analysis


    Enough for a badge!

    The project MUST use at least one static analysis tool with rules or approaches to look for common vulnerabilities in the analyzed language or environment, if there is at least one FLOSS tool that can implement this criterion in the selected language. [static_analysis_common_vulnerabilities]
    Static analysis tools that are specifically designed to look for common vulnerabilities are more likely to find them. That said, using any static tools will typically help find some problems, so we are suggesting but not requiring this for the 'passing' level badge.

    Bandit and CodeQL both implement vulnerability-pattern rules. Bandit scans for the Python-specific common-weakness patterns (B-series: shell injection, insecure deserialization, weak crypto calls, hardcoded secrets, etc.). CodeQL's default query suite covers OWASP/CWE categories (injection, path traversal, SSRF, XSS).


  • Dynamic code analysis


    Enough for a badge!

    If the software produced by the project includes software written using a memory-unsafe language (e.g., C or C++), then at least one dynamic tool (e.g., a fuzzer or web application scanner) MUST be routinely used in combination with a mechanism to detect memory safety problems such as buffer overwrites. If the project does not produce software written in a memory-unsafe language, choose "not applicable" (N/A). [dynamic_analysis_unsafe]
    Examples of mechanisms to detect memory safety problems include Address Sanitizer (ASAN) (available in GCC and LLVM), Memory Sanitizer, and valgrind. Other potentially-used tools include thread sanitizer and undefined behavior sanitizer. Widespread assertions would also work.

    compose-lint is written in pure Python (a memory-safe language) with PyYAML as the sole runtime dependency. No C/C++/unsafe-Rust code is produced or shipped.



This data is available under the Community Data License Agreement – Permissive, Version 2.0 (CDLA-Permissive-2.0). This means that a Data Recipient may share the Data, with or without modifications, so long as the Data Recipient makes available the text of this agreement with the shared Data. Please credit Todd Matens and the OpenSSF Best Practices badge contributors.

Project badge entry owned by: Todd Matens.
Entry created on 2026-04-12 08:08:52 UTC, last updated on 2026-05-03 00:49:57 UTC. Last achieved passing badge on 2026-04-19 05:15:06 UTC.