Principal Software Engineer

About the role

Principal Network Transport Engineer

The Principal Network Transport Engineer role is central to the Engine Networking Team. This position focuses on architecting and owning the network transport layer that powers shared 3D worlds across the platform. The core mission involves designing protocols that ensure reliable movement of game state, building low latency systems, and maintaining synchronization for millions of concurrent players globally. Success in this role means enabling the nearly synchronous world that players experience on Roblox.

This role demands deep expertise in network systems and a passion for solving complex technical challenges at scale. You will analyze packet flows to eliminate milliseconds of delay and work closely with infrastructure teams to align services with platform objectives. The position requires guiding junior staff, reviewing code for correctness, and ensuring long term maintainability through rigorous testing and staged rollouts.

Key Responsibilities

Architecting and owning the network transport layer is a multifaceted responsibility. You will design core network protocols responsible for moving the game state reliably across diverse environments. Building low latency systems capable of connecting millions of concurrent players worldwide is a fundamental duty. Analyzing packet flows to reduce delay and improve synchronization directly impacts player experience.

You will review code with engineers to uphold correctness and maintainability over the life of the product. Shipping changes safely involves comprehensive tests, monitoring, and staged rollouts to mitigate risk. Partnering with infrastructure teams ensures network services align with the broader platform goals. Guiding junior staff through design discussions and technical best practices is an expected contribution. Evaluating tools and libraries helps strengthen networking capabilities across all devices Roblox supports.

Qualifications and Experience

Candidates must possess significant experience with game networking from a game engine or studio background. A proven track record working on a powerful user-space network stack is essential. This experience should involve solving problems related to scale, performance, latency, and throughput in client/server environments. Operating a very large multithreaded distributed system that connects millions of users worldwide is a requirement.

A deep understanding of the network stack, combined with strong systems-level C++ programming skills, is mandatory. You must be fascinated by the actual work the CPU performs, including smart pointers, templates, virtual functions, and blocks of memory. Experience with Linux networking, QoS, and congestion control algorithms is expected. A keen focus on optimizing every millisecond of network exchanges is crucial. Understanding what happens at the operating system level when code completes is vital for diagnosing networking issues.

You must have hands-on experience supporting all devices Roblox runs on, ranging from desktop clients to mobile phone clients and console clients. A comprehensive understanding of a game engine and how its networking model functions is non-negotiable. Familiarity with open source projects that are widely used is considered a strong asset for this position.

Compensation and Work Location

For this role based in San Mateo, CA, the starting base pay range is $293,800 to $343,340 USD. The actual base pay may vary based on professional background, training, work experience, location, business needs, and market demand. This range is subject to change and may be modified in the future. All full-time employees are eligible for equity compensation and benefits as described on the official total rewards page.

Roles based in an office are generally onsite Tuesday, Wednesday, and Thursday, with optional presence on Monday and Friday unless otherwise noted. Roblox provides equal employment opportunities to all employees and applicants. The company prohibits discrimination and harassment of any type without regard to race, color, religion, age, sex, national origin, disability status, genetics, protected veteran status, sexual orientation, gender identity or expression. Reasonable accommodations are available for candidates during the application process.

What you'll do

• Meet the bar Practical notes