Running with cucumber-js

decisium run already runs inside cucumber-js and loads your cucumber.{js,mjs,cjs,json,yaml}. Use raw npx cucumber-js only when your project already runs cucumber that way (CI scripts, IDE run buttons) and you want Decisium Steps in the same run as your own step definitions. cucumber-js imports Decisium from the project, so this needs the per-project install: npm install --save-dev decisium.

// cucumber.mjs
export default {
  import: ["node_modules/decisium/dist/steps.js", "steps/**/*.js"],
  format: ["decisium/formatter"],
  worldParameters: { decisium: { record: "none" } },
};

npx cucumber-js features/checkout.feature

import takes file paths, not package names, hence the node_modules/... path. The options in worldParameters.decisium are the same as decisium run's flags; see Configuration.