Senior Software Engineer, Cobalt

Tubi•San Francisco, CA

19h•Hybrid

About The Position

We are hiring a Senior Software Engineer to build Tubi's native app runtime for connected TVs on Cobalt, the lightweight, open-source browser engine behind YouTube on living room devices. You will own the layer between Tubi's React app and the device: the Cobalt engine, its Starboard porting layer, and new native components we write in C++ and Rust. The goal is a Tubi app that launches faster, uses less memory, and behaves the same on every device, starting with Fire TV and expanding to other CTV platforms. This is a hands-on, high-ownership role on a small team, working closely with our web engineers, QA, and device partners. This is a hybrid role which is two days in the SF office.

Requirements

6+ years of professional software engineering, most of it in systems or native code
Expert-level modern C++ (C++17/20): memory management, concurrency, templates, and debugging large codebases
Strong production experience in Rust: ownership and lifetimes, async, unsafe code, and C/C++ interop (FFI, bindgen/cxx)
Experience with large C++ build systems (GN/Ninja, CMake, or Bazel) and cross-compiling for ARM and embedded Linux or Android targets
Hands-on performance work: profiling CPU, memory, and startup time with tools like perf, Perfetto, or heaptrack, and turning findings into measurable wins
Comfort debugging on real hardware: Android NDK, adb, native crash analysis, and symbolication
Clear written communication and a track record of leading technical initiatives across teams

Nice To Haves

Experience with Cobalt, Starboard, Chromium, or another browser engine (Blink, WebKit, Servo)
JavaScript engine internals, especially V8: code caching, snapshots, or GC tuning
Graphics on embedded devices: OpenGL ES, Skia, or WebGPU
Media pipelines: MSE/EME, ExoPlayer or native players, demuxers, Widevine or PlayReady DRM
Shipping on TV platforms such as Fire TV, Android TV, Samsung Tizen, LG webOS, or Roku
Open-source contributions to C++ or Rust projects
Enough React and TypeScript to work with the web app running on top of the engine

Responsibilities

Build, integrate, and ship Cobalt as the runtime for Tubi's CTV apps, packaged as a native library inside our Android (Fire TV) app and later on other platforms
Implement and maintain Starboard platform integrations: graphics, input, audio/video playback, DRM, and system services
Write new native modules in modern C++ and Rust, including safe FFI boundaries between the two
Drive startup and memory performance on low-end, memory-constrained devices (1 GB RAM class): profile, measure, and fix
Keep us current with upstream Cobalt releases, track and contribute fixes upstream, and manage security patches for the engine we ship
Work with media and playback teams on video pipeline needs such as demuxing, adaptive streaming, and ad playback
Build tooling that runs the Tubi app on Cobalt on developer machines and in CI, so we can test UI and automation without a device farm
Work directly with device partners' engineering teams on platform issues
Mentor engineers and raise the team's native and systems engineering bar