kotiko

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.
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These are the Gold level criteria. You can also view the Passing or Silver level criteria.

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

        

 Basics 3/5 ●

  • General

    Note that other projects may use the same name.

    Learn languages while you browse: Kotiko swaps words on the pages you read for the words you're learning, in any language. Local-first browser extension with an optional self-hosted server.

    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.

  • Prerequisites


    Enough for a badge!

    The project MUST achieve a silver level badge. [achieve_silver]

  • Project oversight


    Not enough for a badge.

    The project MUST 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.

    Kotiko has two maintainers since 2026-10-06, but every commit so far was written by the lead maintainer, so the bus factor is still 1 in practice. We are working on it: the architecture, the assurance case and the coding standards are written down, every planned piece of work in slices/ is a buildable spec, and GOVERNANCE.md says how the maintainers continue without any one of them. https://github.com/ScriptKittyOS/kotiko/blob/main/docs/governance/continuity.md#bus-factor


    Not enough for a badge.

    The project MUST have at least two unassociated significant contributors. (URL required) [contributors_unassociated]
    Contributors are associated if they are paid to work by the same organization (as an employee or contractor) and the organization stands to benefit from the project's results. Financial grants do not count as being from the same organization if they pass through other organizations (e.g., science grants paid to different organizations from a common government or NGO source do not cause contributors to be associated). Someone is a significant contributor if they have made non-trivial contributions to the project in the past year. Examples of good indicators of a significant contributor are: written at least 1,000 lines of code, contributed 50 commits, or contributed at least 20 pages of documentation.

    Not yet. All significant contributions in the past year come from one person. Issues, Discussions and translations are open to everyone, and small tasks will be labelled for newcomers.


  • Other


    Enough for a badge!

    The project MUST include a license statement in each source file. This MAY be done by including the following inside a comment near the beginning of each file: SPDX-License-Identifier: [SPDX license expression for project]. [license_per_file]
    This MAY also be done by including a statement in natural language identifying the license. The project MAY also include a stable URL pointing to the license text, or the full license text. Note that the criterion license_location requires the project license be in a standard location. See this SPDX tutorial for more information about SPDX license expressions. Note the relationship with copyright_per_file, whose content would typically precede the license information.

    Every source code file carries an SPDX license identifier comment for Apache-2.0 near the top (another SPDX identifier where third-party data says so). Files that can't carry a comment (JSON, images), plus Markdown, test fixture pages and two formatter configs, get it through REUSE.toml, and reuse lint runs on every pull request as a required check.


 Change Control 3/4 ●

  • Public version-controlled source repository


    Enough for a badge!

    The project's source repository MUST use a common distributed version control software (e.g., git or mercurial). [repo_distributed]
    Git is not specifically required and projects can use centralized version control software (such as subversion) with justification.

    git, hosted on GitHub: https://github.com/ScriptKittyOS/kotiko


    Not enough for a badge.

    The project MUST clearly identify small tasks that can be performed by new or casual contributors. (URL required) [small_tasks]
    This identification is typically done by marking selected issues in an issue tracker with one or more tags the project uses for the purpose, e.g., up-for-grabs, first-timers-only, "Small fix", microtask, or IdealFirstBug. These new tasks need not involve adding functionality; they can be improving documentation, adding test cases, or anything else that aids the project and helps the contributor understand more about the project.

    Not yet. The good first issue and help wanted labels exist, but no issue carries them yet. Small tasks will be filed with those labels and linked from CONTRIBUTING.md.


    Enough for a badge!

    The project MUST require two-factor authentication (2FA) for developers for changing a central repository or accessing sensitive data (such as private vulnerability reports). This 2FA mechanism MAY use mechanisms without cryptographic mechanisms such as SMS, though that is not recommended. [require_2FA]

    The ScriptKittyOS GitHub organization requires two-factor authentication for every member, so nobody can push to the repository, change its settings or read private vulnerability reports without it. GOVERNANCE.md requires it for store accounts too.


    Enough for a badge!

    The project's two-factor authentication (2FA) SHOULD use cryptographic mechanisms to prevent impersonation. Short Message Service (SMS) based 2FA, by itself, does NOT meet this criterion, since it is not encrypted. [secure_2FA]
    A 2FA mechanism that meets this criterion would be a Time-based One-Time Password (TOTP) application that automatically generates an authentication code that changes after a certain period of time. Note that GitHub supports TOTP.

    GOVERNANCE.md requires maintainers (and a steward, if one is named) to protect their GitHub and store accounts with a passkey, a security key or an authenticator app, not SMS.


 Quality 6/7 ●

  • Coding standards


    Enough for a badge!

    The project MUST document its code review requirements, including how code review is conducted, what must be checked, and what is required to be acceptable. (URL required) [code_review_standards]
    See also two_person_review and contribution_requirements.

    docs/CODE_REVIEW.md documents how code review is done and what is required: CI's required checks pass first; a reviewer who isn't the author reads the whole diff and approves or requests changes line by line; every review thread is resolved before merging; and a checklist of what must be true (does what it says and matches its spec, tested with a regression test for each fix, trust boundaries and input validation hold, no HTML from data, privacy inventory updated, dependencies within the license and dependency policy, no English or single-language assumption, accessibility and size budgets, docs and changelog, DCO sign-off), plus the standard of evidence for any claim. CONTRIBUTING.md links it. https://github.com/ScriptKittyOS/kotiko/blob/main/docs/CODE_REVIEW.md


    Not enough for a badge.

    The project MUST have at least 50% of all proposed modifications reviewed before release by a person other than the author, to determine if it is a worthwhile modification and free of known issues which would argue against its inclusion [two_person_review]

    Not yet. Kotiko has a second maintainer since 2026-10-06, but the merged pull requests so far were checked by their author and CI only. The next steps are reviews by the second maintainer, then an approving review required on main for every change.


  • Working build system


    Enough for a badge!

    The project MUST have a reproducible build. If no building occurs (e.g., scripting languages where the source code is used directly instead of being compiled), select "not applicable" (N/A). (URL required) [build_reproducible]
    A reproducible build means that multiple parties can independently redo the process of generating information from source files and get exactly the same bit-for-bit result. In some cases, this can be resolved by forcing some sort order. JavaScript developers may consider using npm shrinkwrap and webpack OccurrenceOrderPlugin. GCC and clang users may find the -frandom-seed option useful. The build environment (including the toolset) can often be defined for external parties by specifying the cryptographic hash of a specific container or virtual machine that they can use for rebuilding. The reproducible builds project has documentation on how to do this.

    The extension zips, the only built release files, are reproducible by anyone: the build uses entries sorted by path, the commit's timestamp, fixed permissions and a pinned pure-JavaScript deflate, so the bytes don't depend on the machine or time zone. The release workflow builds twice and compares, and docs/reproducible-builds.md shows how to rebuild a release from its tag and check it against the published SHA256SUMS. The server is released as source. https://github.com/ScriptKittyOS/kotiko/blob/main/docs/reproducible-builds.md


  • Automated test suite


    Enough for a badge!

    A test suite MUST be invocable in a standard way for that language. (URL required) [test_invocation]
    For example, "make check", "mvn test", or "rake test" (Ruby).

    npm test (Node's built-in test runner) for the extension and mix test for the server, the standard commands of each ecosystem; npm run e2e runs the Playwright end-to-end tests. https://github.com/ScriptKittyOS/kotiko/blob/main/CONTRIBUTING.md#setup


    Enough for a badge!

    The project MUST implement continuous integration, where new or changed code is frequently integrated into a central code repository and automated tests are run on the result. (URL required) [test_continuous_integration]
    In most cases this means that each developer who works full-time on the project integrates at least daily.

    Every change reaches main through a short-lived pull request, and GitHub Actions runs every test suite, the linters and the audits on each pull request and each push to main; main requires 8 checks to pass. https://github.com/ScriptKittyOS/kotiko/actions/workflows/ci.yml


    Enough for a badge!

    The project MUST have FLOSS automated test suite(s) that provide at least 90% statement coverage if there is at least one FLOSS tool that can measure this criterion in the selected language. [test_statement_coverage90]

    Statement coverage is above 90 % and enforced by FLOSS tools in CI and in the release workflow: the server's ExUnit suite covers 91.6 % of lines and fails below 90 % (mix test --cover, threshold in mix.exs), and the extension's Node test suites cover 93.9 % of lines and fail below 90 % (npm run coverage). https://github.com/ScriptKittyOS/kotiko/blob/main/CONTRIBUTING.md#tests


    Enough for a badge!

    The project MUST have FLOSS automated test suite(s) that provide at least 80% branch coverage if there is at least one FLOSS tool that can measure this criterion in the selected language. [test_branch_coverage80]

    The extension's Node test suites cover 84.5 % of branches and fail below 80 % (npm run coverage, node --test with --test-coverage-branches=80), in CI and before every release. For the Elixir server no FLOSS tool measures branch coverage (Erlang's cover tool counts lines only), so its 90 % line gate applies instead. https://github.com/ScriptKittyOS/kotiko/blob/main/CONTRIBUTING.md#tests


 Security 3/5 ●

  • 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 software produced by the project MUST 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 MUST 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]

    Kotiko's own outbound traffic uses HTTPS by default: model providers, OpenRouter, Telegram and Wiktionary. The server listens on 127.0.0.1 by default, so its plain-HTTP API doesn't leave the computer unless the owner sets BIND to another address; then the server logs a warning at start (daily for a public address), and the extension warns under the address field when the token would cross a network unencrypted. A plain-HTTP model endpoint (such as a local Ollama) is used only when the user enters one.


    Enough for a badge!

    The software produced by the project MUST, 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]

    TLS comes from Erlang/OTP (26 and newer, which offer TLS 1.2 and 1.3 by default) for the server's outbound requests and from the browser for the extension. Kotiko never sets or lowers the TLS version.


  • Secured delivery against man-in-the-middle (MITM) attacks


    Not enough for a badge.

    The project website, repository (if accessible via the web), and download site (if separate) MUST include key hardening headers with nonpermissive values. (URL required) [hardened_site]
    Note that GitHub and GitLab are known to meet this. Sites such as https://securityheaders.com/ can quickly check this. The key hardening headers are: Content Security Policy (CSP), HTTP Strict Transport Security (HSTS), X-Content-Type-Options (as "nosniff"), and X-Frame-Options. Fully static web sites with no ability to log in via the web pages could omit some hardening headers with less risk, but there's no reliable way to detect such sites, so we require these headers even if they are fully static sites.

    The repository (https://github.com/ScriptKittyOS/kotiko) and its release downloads are served by GitHub with HTTP Strict Transport Security, a Content Security Policy, X-Frame-Options: deny and X-Content-Type-Options: nosniff. The project website kotiko.org is not published yet; it is to be served through Cloudflare with the same headers before it goes live.


  • Other security issues


    Not enough for a badge.

    The project MUST have performed a security review within the last 5 years. This review MUST consider the security requirements and security boundary. [security_review]
    This MAY be done by the project members and/or an independent evaluation. This evaluation MAY be supported by static and dynamic analysis tools, but there also must be human review to identify problems (particularly in design) that tools cannot detect.

    Not yet as gold requires. A line-by-line adversarial review with probes of the extension and the server (2026-10-01, docs/research/06-adversarial-qa.md) found and fixed an authentication bypass and other issues, but it predates the written security requirements. A pre-release review by three independent reviewers against the security requirements and trust boundaries is planned before the first store release; its report will be published in docs/security.


    Enough for a badge!

    Hardening mechanisms MUST be used in the software produced by the project so that software defects are less likely to result in security vulnerabilities. (URL required) [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).

    Extension pages run under an explicit content security policy (script-src 'self'; object-src 'self') with no inline scripts, and ESLint forbids HTML string sinks (innerHTML, outerHTML, insertAdjacentHTML) so a bug can't turn word data into markup. The server checks the Host header against an allowlist before anything else (against DNS rebinding), caps request bodies, sends no CORS headers, marks answers no-store, binds to loopback by default, compares tokens in constant time, and filters secrets out of logs. Planned: X-Content-Type-Options and similar headers on server responses, and a sandboxed systemd unit. Evidence: https://github.com/ScriptKittyOS/kotiko/blob/main/extension/manifest.json and https://github.com/ScriptKittyOS/kotiko/blob/main/docs/security/assurance-case.md


 Analysis 2/2 ●

  • Dynamic code analysis


    Enough for a badge!

    The project MUST apply at least one dynamic analysis tool to any proposed major production release of the software produced by the project before its release. [dynamic_analysis]
    A dynamic analysis tool examines the software by executing it with specific inputs. For example, the project MAY use a fuzzing tool (e.g., American Fuzzy Lop) or a web application scanner (e.g., OWASP ZAP or w3af). In some cases the OSS-Fuzz project may be willing to apply fuzz testing to your project. For purposes of this criterion the dynamic analysis tool needs to vary the inputs in some way to look for various kinds of problems or be an automated test suite with at least 80% branch coverage. The Wikipedia page on dynamic analysis and the OWASP page on fuzzing identify some dynamic analysis tools. The analysis tool(s) MAY be focused on looking for security vulnerabilities, but this is not required.

    Property-based testing is the dynamic analysis, and it runs on every pull request and again in the release workflow before anything is built. The extension's pure code (the page matcher, URL checks, bulk-add parsing, backup read and restore, casing, the word-list check) is tested with fast-check, and the server's request validation, word spec, settings parsing, language tags, text cleaning, redaction and backup round trips with StreamData; each run uses a new seed, and a failing seed can be replayed. It has found real defects: a word with Å or Ņ made the server answer 500, a repeated query parameter did the same, and a re-add brought back a form the learner had removed; each was fixed with a regression test. https://github.com/ScriptKittyOS/kotiko/blob/main/CONTRIBUTING.md#tests


    Enough for a badge!

    The project SHOULD include many run-time assertions in the software it produces and check those assertions during dynamic analysis. [dynamic_analysis_enable_assertions]
    This criterion does not suggest enabling assertions during production; that is entirely up to the project and its users to decide. This criterion's focus is instead to improve fault detection during dynamic analysis before deployment. Enabling assertions in production use is completely different from enabling assertions during dynamic analysis (such as testing). In some cases enabling assertions in production use is extremely unwise (especially in high-integrity components). There are many arguments against enabling assertions in production, e.g., libraries should not crash callers, their presence may cause rejection by app stores, and/or activating an assertion in production may expose private data such as private keys. Beware that in many Linux distributions NDEBUG is not defined, so C/C++ assert() will by default be enabled for production in those environments. It may be important to use a different assertion mechanism or defining NDEBUG for production in those environments.

    Under test, the extension runs with an assertion mode (globalThis.KOTIKO_ASSERT, set only by the test harness and never by the shipped extension): the matcher checks every scan's matches (bounds, text, order, no overlap), the backup restore plan checks its counts and that it never writes a deleted word, and the word-list check verifies every word is kept or counted. The property-based tests drive these paths with generated input. The server relies on Elixir's pattern matches and guards, which already stop on a broken invariant in production. https://github.com/ScriptKittyOS/kotiko/blob/main/CONTRIBUTING.md#tests



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Project badge entry owned by: Ayla Croft.
Entry created on 2026-10-06 18:38:00 UTC, last updated on 2026-10-06 22:13:39 UTC. Last achieved passing badge on 2026-10-06 19:36:22 UTC.