Founding Mobile Engineer

About the Company4C Software is a prediction markets company connecting some of the largest sports betting market makers and traders in the world. Over the last 12 months, more than $1B has been traded across the platforms we support (4casters & 4cx).We are a small team of fewer than 10 people and have been working in prediction markets since 2017. We value high-agency, hungry builders who combine strong fundamentals with modern AI tools. The company is profitable and on pace for $2M–$3M in revenue this year.We currently have a web app built in Vue, with backend routes, APIs, and core infrastructure already in place. We are now building a dedicated mobile app in React Native and are looking for someone to own the mobile product from its first version through scale.We are looking for builders, not managers. The goal is for you to be the main person architecting and building this app. You should be able to deliver a working product independently. Other team members will help with design, product feedback, and polish, but the core architecture and buildout of the mobile app will rely on you. A major part of this role will be making the right technical decisions around speed, maintainability, and long-term app architecture.This role is for a self-starting builder who uses AI tools effectively, can independently deliver a working mobile product, and wants to own a major product long term. You should have experience shipping meaningful mobile apps, features, or side projects. You will be taking an already-profitable, high-volume product and turning it into a polished mobile app experience that can scale.ResponsibilitiesYou will be responsible for:Building the mobile app, likely in React NativeOwning the core architecture and buildout of the mobile productDeciding how to reuse, improve, or replace parts of the existing Vue web appWorking with existing APIs, backend routes, and real-time data flowsOwning mobile UX for markets, order entry, account flows, positions, and trading featuresImproving performance, reliability, and app quality over timeOwning the mobile app as it scalesIdeal BackgroundWe are looking for someone with:Strong React Native experienceExperience shipping meaningful mobile apps, features, or side projectsGood design and product instinctsComfort with real-time, user-facing productsExperience using prediction markets, sports betting, trading, fintech, crypto, or exchangesAbility to work independently and deliver a working productVue experience helpful, but not requiredChicago-based or open to relocating preferredCompensationCompensation is $150,000–$200,000 base salary + equity, depending on experience and fit.