Principal Software Engineer, Backend – Full or Part Time

Overview

In this role you will help build a scalable technology platform powering Autotrader and external automotive data sources. You will work with a cross-functional team to improve service availability and latency, ensuring sub-100 ms responses for thousands of requests per second across 50+ client applications. As a principal engineer, you will shape system design, mentor engineers, and drive technical projects from concept to delivery. This is a collaborative, high-impact position at a heritage brand that values people and teamwork. You’ll join a growth-focused tech community that embraces modern streaming and search technologies to transform the car-buying journey.

Pay / Benefits

• salary 60,000 – 80,000
• plus 10% shares awarded yearly over 3 years
• 28 days holiday + bank holidays
• comprehensive private medical cover
• pension scheme: employer 7% / employee 5%
• car salary sacrifice scheme

Responsibilities

• Ensure service availability and responsiveness improvements
• Design and architect scalable systems for high throughput
• Lead and deliver technical projects across teams
• Mentor and coach engineers, promote best practices
• Engage in code reviews, pairing, and cross-functional collaboration
• Work on platforms handling thousands of requests per second with sub-100 ms latency
• Collaborate with multiple client applications and external data sources

Key requirements

• Thorough understanding of Java and the JVM
• Knowledge of server-side frameworks such as Spring
• Web application design and RESTful API know-how
• Structured approach to programming and testing (TDD)
• Experience mentoring, coaching and sharing technical expertise
• Architectural and system design knowledge
• Experience leading and delivering technical projects
• SQL/Relational databases
• Document/Map based storage (e.g., MongoDB)
• Working with Kafka messaging/streaming

• collaboration
• mentoring and coaching
• clear communication
• Java/JVM
• Spring
• RESTful API design

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