Proven experience building libraries, reusable components, or similar modular architecture Strong background developing, documenting, and scaling RESTful APIs Proficiency with Docker or similar container platforms Solid testing experience using Jest, Mocha, Sinon, Chai, Vitest, or equivalent tools Strong English communication skills Deep understanding of performance considerations and best practices in large-scale systems Strong awareness of security principles and ability to identify and mitigate vulnerabilities Experience working with integration workflows, API specifications, or developer documentation