Senior Frontend Engineer API/Interface Design

42dot Inc.; Warszawa; On-site; PLN 170,000 - 230,000; Full time

Job summary

42dot Inc. is seeking a Senior Frontend Engineer to shape the user-facing layer of our Software Defined Vehicle platform.

You will build dashboards, variant management, partner portals, and tooling that empower internal engineers and external partners to interact with our SDV OS tooling. You will work with real-time vehicle state dashboards, public API contracts, and 3D vehicle visualizations, collaborating closely with design and backend teams.

Qualifications

• 5+ years production experience with React and TypeScript.
• Experience designing and evolving OpenAPI 3.x specifications and tooling (validators, mocks, client generators).
• Strong schema-first instincts (Zod, JSON Schema, runtime validation).
• Solid understanding of REST and streaming protocols (Server-Sent Events, WebSocket).
• Practical experience integrating 3D content in the browser with three.js or react-three-fiber.
• Strong code review culture and collaboration with backend and design counterparts.
• Fluent English.

Responsibilities

• Design, document and evolve the public REST and Server-Sent Events API surface of our virtual vehicle platform, including OpenAPI specifications and generated partner clients.
• Implement and maintain the production frontend in React and TypeScript: real-time vehicle state dashboards, vehicle variant management, partner-facing portals, configuration and scenario tooling.
• Integrate 3D vehicle assets (glTF) into the frontend using three.js or react-three-fiber, in close collaboration with our product designer.
• Build the developer experience around the schema: typed clients, runtime validation, mocks, contract tests, generated documentation.
• Own resilience of streaming UI components: reconnection, backpressure, multiplexed event handling.
• Participate directly in technical conversations with external integration partners, including API design reviews and partner-facing written guides.

Skills

React

TypeScript

OpenAPI

Schema validation

REST

Server-Sent Events

WebSocket

3D in browser

three.js

code review

English fluency

Education

Bachelor's degree in Computer Science or related field

Tools

three.js

Job description

We are looking for the best

About Us

42dot is a mobility AI company committed to solving mobility challenges with software and AI. As the Global Software Center of Hyundai Motor Group, 42dot pioneers the future of mobility by advancing the development of software-defined vehicles.

We develop safety-first, user-centric software-defined vehicle technologies that deliver the latest performance through continuous updates like smartphones. By advancing software and AI technology, 42dot envisions a world where everything is connected and moves autonomously through a self-managing urban transportation operating system.

Overview

Join our dynamic team as a Senior Frontend Engineer, where you will shape the user-facing layer of our virtual development platform for Software Defined Vehicles (SDV). Your work will define how internal engineering teams and external integration partners experience our SDV OS tooling - from the public API contract that drives partner integrations, through the real-time dashboard that visualizes vehicle state, to the 3D model views that bring the virtual vehicle to life. This is your chance to be at the forefront of automotive innovation, building the developer and partner experience for the autonomous driving platform of the future.

Role and Responsibilities

• Design, document and evolve the public REST and Server-Sent Events API surface of our virtual vehicle platform, including OpenAPI specifications and generated partner clients.

• Implement and maintain the production frontend in React and TypeScript: real-time vehicle state dashboards, vehicle variant management, partner-facing portals, configuration and scenario tooling.

• Integrate 3D vehicle assets (glTF) into the frontend using three.js or react-three-fiber, in close collaboration with our product designer.

• Build the developer experience around the schema: typed clients, runtime validation, mocks, contract tests, generated documentation.

• Own resilience of streaming UI components: reconnection, backpressure, multiplexed event handling.

• Participate directly in technical conversations with external integration partners, including API design reviews and partner-facing written guides.

Qualifications, Experience and Skills

• Bachelor's degree in Computer Science or related field, equivalent practical experience.

• 5+ years of production experience with React and TypeScript, including end-to-end type safety.

• Hands-on experience designing and evolving OpenAPI 3.x specifications and the tooling around them (validators, mocks, client generators).

• Strong schema-first instincts (Zod, JSON Schema, runtime validation at boundaries).

• Solid working understanding of REST and streaming protocols (Server-Sent Events, WebSocket).

• Practical experience integrating 3D content in the browser with three.js or react-three-fiber: scenes, cameras, glTF loading, basic performance tuning.

• Strong code review culture and ability to collaborate with backend and design counterparts.

• Fluent English.

Preferred Qualifications

• Frontend integration testing with Playwright or Cypress, including visual regression workflows.

• Experience writing partner- or developer-facing technical content (HOWTOs, integration guides, release notes).

• Working experience with multi-site, multi-national and multi-contributor teams.

• Knowledge of automotive products, is a plus but not required.

Interview Process

• Application Review - Coding Test - 1st interview - 2nd interview - Offer Negotiation - Hiring

• The screening procedures may vary depending on the position, schedule, or other circumstances.

  You will be individually notified of the screening schedule and results via the email address provided in your application.

Additional Information

• In accordance with fair hiring practices, do not include any personal information unrelated to your job qualifications (e.g., Social Security Number, family relations, marital status, age, photo, physical condition, place of birth, etc.) in your resume.

• All documents must be submitted in PDF format and under 30MB in size.

• 42dot does not accept unsolicited resumes and will not pay fees for any such submissions. Equal Opportunity Statement

• 42dot is an Equal Opportunity Employer. We celebrate diversity and are committed to creating an inclusive environment for all employees, regardless of race, color, religion, sex, sexual orientation, gender identity, national origin, age, disability, or veteran status.

Please review the following information before applying.

• How to work in 42dot, About 42dot Way