{"id":48243,"library":"jsck","title":"JSCK","description":"JSCK (JSON Schema Compiled checK) is a JSON Schema validator for Node.js that compiles schemas into efficient validation trees for performance. It supports JSON Schema drafts 3 and 4 with some caveats (e.g., no remote refs, no uniqueItems). Current stable version is 0.3.2. It is faster than many alternatives due to compilation, but is no longer actively maintained (last release in 2016). Key differentiators: compiles schema to functions, supports draft 3 and 4, but lacks modern draft 6/7/2019-09 support.","status":"maintenance","version":"0.3.2","language":"javascript","source_language":"en","source_url":"ssh://git@github.com/pandastrike/jsck","tags":["javascript"],"install":[{"cmd":"npm install jsck","lang":"bash","label":"npm"},{"cmd":"yarn add jsck","lang":"bash","label":"yarn"},{"cmd":"pnpm add jsck","lang":"bash","label":"pnpm"}],"dependencies":[],"imports":[{"note":"Package uses CoffeeScript; ESM import works if bundler supports it. CommonJS require is also valid as the package exposes a CommonJS module.","wrong":"const JSCK = require('jsck')","symbol":"default","correct":"import JSCK from 'jsck'"},{"note":"Constructor takes only schema object; no options. Use for Draft 4 schemas.","wrong":"new JSCK.draft4(schema, options)","symbol":"draft4","correct":"new JSCK.draft4(schema)"},{"note":"Similar to draft4; no options argument.","wrong":"new JSCK.draft3(schema, {})","symbol":"draft3","correct":"new JSCK.draft3(schema)"}],"quickstart":{"code":"import JSCK from 'jsck';\n\nconst schema = {\n  type: 'object',\n  properties: {\n    name: { type: 'string' },\n    age: { type: 'integer', minimum: 0 }\n  },\n  required: ['name']\n};\n\nconst validator = new JSCK.draft4(schema);\n\nconst validDoc = { name: 'Alice', age: 30 };\nconst result = validator.validate(validDoc);\nconsole.log(result.valid); // true\n\nconst invalidDoc = { age: -5 };\nconst result2 = validator.validate(invalidDoc);\nconsole.log(result2.valid); // false\nconsole.log(result2.errors); // array of error objects","lang":"javascript","description":"Shows basic usage: create a Draft 4 validator, validate a document, and inspect errors."},"warnings":[{"fix":"Consider switching to modern validators like Ajv or @cfworker/json-schema.","message":"JSCK is no longer actively maintained.","severity":"deprecated","affected_versions":">=0.0.0"},{"fix":"Use a validator that supports remote references, such as Ajv.","message":"No support for remote $ref (refRemote).","severity":"gotcha","affected_versions":"*"},{"fix":"Use another validator if you need to enforce unique arrays.","message":"No support for uniqueItems.","severity":"gotcha","affected_versions":"*"},{"fix":"Avoid complex 'id' usage or switch to a validator with full support.","message":"Limited support for 'id' attribute; only top-level and non-JSON-pointer fragments.","severity":"gotcha","affected_versions":"*"},{"fix":"None for consumers; purely informational.","message":"Package is CoffeeScript; source requires CoffeeScript toolchain to develop.","severity":"gotcha","affected_versions":"*"}],"env_vars":null,"search_vec":"'0.3.2':44 '2016':63 '3':28,72 '4':30,74 '6/7/2019-09':79 'activ':58 'altern':50 'caveat':33 'check':6 'compil':5,15,53,66 'current':40 'differenti':65 'draft':27,71,78 'due':51 'e.g':34 'effici':18 'faster':47 'function':69 'javascript':81 'jsck':1,2 'json':3,9,25 'key':64 'lack':76 'last':60 'longer':57 'maintain':59 'mani':49 'modern':77 'node.js':13 'perform':22 'ref':37 'releas':61 'remot':36 'schema':4,10,16,26,67 'stabl':41 'support':24,70,80 'tree':20 'uniqueitem':39 'valid':11,19 'version':42","created_at":"2026-06-07T16:55:38.219516+00:00","updated_at":"2026-06-07T16:55:38.219516+00:00","problems":[{"fix":"Run 'npm install jsck' and ensure node_modules contains it.","cause":"Package not installed or misspelled.","error":"Error: Cannot find module 'jsck'"},{"fix":"Use 'const JSCK = require('jsck');' then 'new JSCK.draft4(schema)'.","cause":"Incorrect import: using require as default instead of property.","error":"TypeError: JSCK.draft4 is not a constructor"},{"fix":"Either avoid using 'format' or use a plugin/extend JSCK (see docs).","cause":"JSCK does not support the 'email' format by default.","error":"ValidationError: unknown format 'email'"}],"ecosystem":"npm","meta_description":null,"install_score":null,"quickstart_score":null,"quickstart_tag":null,"pypi_latest":null,"cli_name":null,"cli_version":null,"type":"library","homepage":"https://github.com/pandastrike/jsck#readme","github":"ssh://git@github.com/pandastrike/jsck","docs":null,"changelog":null,"pypi":null,"npm":"jsck","openapi_spec":null,"status_page":null,"smithery":null,"categories":["testing"],"base_url":null,"auth_type":null,"provenance":{"verified_status":null,"verified_at":null,"last_verified":"2026-06-07","next_check":"2026-09-05","install_tag":null}}