CodeSampleX

Sample

lookup MIME type metadata and extensions in mime-db

sha256:6c1dfc987b0995d378c70092b5b3e3b468e22be8dfefe5dfd8a7f8cb73366be6

Publication state. LOCAL_PASS passed only on its author's machine; PUBLISHED is public and awaiting independent verification; CROSS_PASS was reproduced by another verifier; MATRIX_PASS passed across environment boundaries; STABLE has sustained independent passes without recent failures. Evidence strength. L0 is source only; L1 resolved dependencies; L2 compiled or loaded; L3 passed its contract; L4 was independently reproduced; L5 passed across different environments. MIT-0

Execution evidence

Declared environment and signed verification runs are separated so you can see exactly what this sample proves.

Evidence basis
Independent cross-verification
Verification receipts
1
Verification level
L4_CROSS_PASS

Declared environment

Execution context
node 22
Operating system
linux
Architecture
x64
Runtime
node 22
Language
javascript
Package manager
npm 10

Verification-run environments

node 22 · linux alpine/x64 · docker PASS
Execution context
node 22
Operating system
linux alpine · musl
Architecture
x64
Runtime
node 22
Language
javascript
Package manager
npm
Execution
container · docker

CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · node-typescript@1 · 2026-08-19

Case

HOW
Goal
lookup MIME type metadata and extensions in mime-db
Packages
Symbols
  • mime-db
Environment
node 22
Created
2026-08-18T18:07:59Z

Contract

  1. db is an object mapping MIME type strings to metadata entries
  2. getType performs case-insensitive lookup and returns metadata entry with source, extensions, and charset
  3. getExtensions returns array of associated file extensions or empty array
  4. getDefaultExtension returns primary file extension without leading dot
  5. isCompressible returns boolean compressibility status of the media type
  6. findTypeByExtension looks up media type corresponding to a file extension
  7. getSource returns database origin source such as iana or apache
  8. getCharset returns defined charset encoding or undefined

Files

  • PROMPT.md
  • csx.json
  • index.js
  • package-lock.json
  • package.json
  • spec.json
  • test/contract.js

Download the source artifact (tar.gz)

Origin Seeder

anonymous

Verification receipts

  • node 22 · linux alpine/x64 · docker PASS
    CONTAINER_RUN compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS node-typescript@1
    ed25519:2175b912ea1c23b1