{"id":18260,"library":"cypress-parallel","title":"cypress-parallel","description":"A CLI tool that runs Cypress test specs in parallel on the same machine, reducing execution time by up to 40%. It shards spec files across a configurable number of threads, each running a Cypress command. Version 0.15.0 is current; releases are occasional with bug fixes and dependency updates. Differentiators: no external CI service required, supports weight files for balanced sharding, mono-repo support via reporterModulePath, and strict mode for validation. Peer dependency on cypress-multi-reporters (^2.0.5). Active maintenance with recent dependency security bumps.","status":"active","version":"0.15.0","language":"javascript","source_language":"en","source_url":"https://github.com/tnicola/cypress-parallel","tags":["javascript","cypress","parallel","local","sharding"],"install":[{"cmd":"npm install cypress-parallel","lang":"bash","label":"npm"},{"cmd":"yarn add cypress-parallel","lang":"bash","label":"yarn"},{"cmd":"pnpm add cypress-parallel","lang":"bash","label":"pnpm"}],"dependencies":[{"reason":"Peer dependency, used for test reporting output","package":"cypress-multi-reporters","optional":true}],"imports":[{"note":"The -s flag expects an npm script name, not a cypress command. Define a script in package.json first.","wrong":"npx cypress-parallel -s cypress run -t 2","symbol":"cli usage","correct":"npx cypress-parallel -s cy:run -t 2 -d cypress/e2e"},{"note":"Can be devDependency, but --save-dev is optional.","wrong":"npm install cypress-parallel --save-dev","symbol":"install","correct":"npm i cypress-parallel"},{"note":"Package has no main export; primarily used as a CLI tool. Importing directly may not work.","wrong":"import { version } from 'cypress-parallel'","symbol":"version","correct":"const version = require('cypress-parallel/package.json').version"}],"quickstart":{"code":"// In package.json:\n// \"scripts\": {\n//   \"cy:run\": \"cypress run\",\n//   \"cy:parallel\": \"cypress-parallel -s cy:run -t 2 -d cypress/e2e\"\n// }\n// Then run:\n// npm run cy:parallel\n\n// Alternative one-liner with npx:\n// npx cypress-parallel -s cy:run -t 2 -d cypress/e2e","lang":"javascript","description":"Install and run cypress-parallel with 2 threads, splitting specs from the cypress/e2e directory."},"warnings":[{"fix":"Update to v0.13.0 or later.","message":"The 'colors' dependency was replaced with '@colors/colors' in v0.13.0 due to a security incident (CVE-2022-24785).","severity":"deprecated","affected_versions":"<0.13.0"},{"fix":"Add -m false to the cypress-parallel command.","message":"Using --strictMode (-m) with cypress-cucumber-preprocessor can cause errors. Disable strict mode if you use that preprocessor.","severity":"gotcha","affected_versions":">=0.8.4"},{"fix":"Define the cypress command in package.json scripts and pass that script name.","message":"The --script (-s) option must be the name of an npm script (e.g., 'cy:run'), not a raw cypress command. Common mistake leads to 'command not found'.","severity":"gotcha","affected_versions":">=0.1"},{"fix":"Add -n path/to/node_modules/cypress-multi-reporters","message":"If using cypress-multi-reporters from a monorepo, the module may not be found. Use --reporterModulePath (-n) to specify the path.","severity":"gotcha","affected_versions":">=0.9.0"},{"fix":"Update to v0.12.0 or ensure -t <= spec count.","message":"The number of threads (-t) should not exceed the number of spec files found. v0.12.0 added a check, but earlier versions may spin up unnecessary threads.","severity":"gotcha","affected_versions":"<0.12.0"}],"env_vars":null,"last_verified":"2026-04-25T00:00:00.000Z","next_check":"2026-07-24T00:00:00.000Z","problems":[{"fix":"Install cypress-multi-reporters: npm i cypress-multi-reporters","cause":"cypress-multi-reporters is not installed or not accessible in the working directory.","error":"Error: Cannot find module 'cypress-multi-reporters'"},{"fix":"Use npx cypress-parallel or install globally: npm i -g cypress-parallel","cause":"cypress-parallel is not installed or npx is used incorrectly.","error":"cypress-parallel: command not found"},{"fix":"Define a script in package.json, e.g., \"cy:run\": \"cypress run\" and use -s cy:run","cause":"Passing cypress command directly to -s instead of an npm script name.","error":"Error: The script name 'cypress run' is not a valid npm script."},{"fix":"Reduce -t to at most the number of spec files.","cause":"More threads than spec files; v0.12.0+ throws this error.","error":"Error: The number of threads (t) cannot be greater than the number of spec files found."}],"ecosystem":"npm","meta_description":null,"install_score":null,"install_tag":null,"quickstart_score":null,"quickstart_tag":null}