Senior React Native Engineer (Latam & North America)

X-Team International; United States; Remote; USD 165,000 - 331,000; Full time

Job summary

X-Team International offers a fully remote contractor role building the mobile architecture behind a real-time trading experience. You will own end-to-end architecture, tackle high-frequency data challenges, and ensure frame budgets are preserved across platforms.

This senior role requires 8+ years in mobile apps with 5+ years in React Native, plus deep expertise in JSI, Fabric, TurboModules, and bridgeless mode. Work remotely from any NA/Latam time zones while collaborating with top brands.

Qualifications

• 8+ years building production mobile applications, including 5+ years in React Native at senior level or above.
• Demonstrable architect-level ownership — you've designed a mobile architecture that other engineers built on for years, not just delivered features.

Responsibilities

• Own the mobile architecture behind a real-time trading experience.
• Collaborate with engineers across the world on high-performance mobile systems.
• Lead architecture decisions and ensure 60–120fps under real-time data load.

Skills

Objective-C

Kotlin

Swift

C++

React Native

Job description

Objective-C

Kotlin

Swift

C++

Work fully remote, globally

Join a team spread across the world and enjoy true location freedom while collaborating with talented engineers everywhere.

Work with top brands

Riot Games, Fox, Coinbase, Epic Games, and so much more.

Gamified community you’ll love

Engage in online events, compete in challenges, and attend Outposts and summits that bring X-Teamers together learning, connecting, and leveling up globally.

Enjoy flexible schedules, wellness stipends, and support to make sure you’re thriving both professionally and personally.

About the Role

This is a contractor role through X-Team. You'll own the mobile architecture behind a real-time trading experience - the kind of app where a dropped frame during a fast market means a trader misses a price. Every screen you touch, from a candlestick chart re-rendering thousands of points a second to an options chain repainting under high-frequency updates, has to hold its frame budget while real market data pushes against it. The legacy bridge is gone. This isn't a New Architecture migration project - it's about going deep on JSI, Fabric, TurboModules, and bridgeless mode, and setting the standards every other engineer on the team builds against.

Open to candidates based in North America or Latam

8+ years building production mobile applications, including 5+ years in React Native at senior level or above

Demonstrable architect-level ownership — you've designed a mobile architecture that other engineers built on for years, not just delivered features inside one

Deep, hands-on experience with React Native's New Architecture: JSI, Fabric, TurboModules, Codegen, and bridgeless mode, including custom native modules and components you wrote yourself

Strong native iOS and Android skills: Swift/Objective-C++ and Kotlin, with real comfort in C++ for shared cores or performance-critical paths

Proven multithreading work in React Native: worklets, worklet runtimes, Reanimated internals, background runtimes, and the serialization/lifetime rules that make them safe

A track record of sustained 60-120fps under real-time data load, with concrete before/after numbers you can walk through

Real-time data experience: high-message-rate WebSocket streaming, backpressure handling, binary protocols, and architectures that decouple ingest rate from render rate

High-performance charting experience in React Native - Skia, GPU canvas, or a custom native renderer - beyond dropping in an off-the-shelf chart library

Expert-level profiling across Hermes, Perfetto/Systrace, Instruments, React DevTools, and Flashlight

The bonus skills:

Experience at a trading, brokerage, crypto exchange, or high-frequency fintech app, or comparable real-time consumer scale elsewhere

Options-specific product work: options chains, multi-leg order tickets, greeks, payoff diagrams, implied volatility surfaces

Nitro Modules, or other experience reducing JSnative call overhead on hot paths

Open source contributions to the React Native ecosystem, or conference/blog work on RN performance

Experience in a regulated environment: security review, certificate pinning, tamper/jailbreak detection, auditability, accessibility compliance

Experience running OTA/CodePush-style release infrastructure with feature-flagged rollouts

Measures before touching code — diagnoses whether a stall is JS thread, UI thread, commit phase, GC, or GPU before reaching for a fix

Comfortable being the final call on hard architectural trade-offs, like deciding when a screen needs a native fallback and owning both sides of it

Writes the design docs and runs the architecture reviews, not just the code — raises the bar for everyone around them

Treats a dropped frame as a bug, not a nice-to-have

Mentors naturally, pairing on the hard traces and sharing what the profiler actually revealed

Our Hiring Process

May change based on various factors (role, profile completeness, etc).

1

Initial Interview

Our recruitment team will review your application and contact you if they'd like to proceed with an initial interview.

Duration: ~ 1 week

2

Skills Assessment

After a successful initial interview, the next step will be an assessment of your technical skills in order to build an 'X-Profile' that we can share with the relevant partner.

Duration: ~ 1 week

3

Interview with Our Partner

We'll schedule an interview for you to meet our partner, during which you'll get to know more details about the specific role you have been matched with.

Duration: ~ 1 week

FAQ

X-Team is committed to providing the ultimate work experience for engineers.

Do you provide paid vacation?

X-Team doesn’t offer paid vacation time, but can arrange for vacation time. We encourage you to incorporate vacation time, health insurance, etc... into your hourly rate.

Will I be working full-time or part-time hours?

At X-Team, we only hire people who can fully dedicate themselves to a project. That means a standard 40 hours per week, Monday through Friday.

Do I need to take care of my own taxes?

Yes. Because we hire you as a full-time contractor, you’ll need to take care of your own taxes. If this is your first time doing so, we recommend you get the advice of a qualified tax advisor to understand the requirements of your country.