Product Engineer — Consumer Mobile

About GACHA

GACHA is building a new way for collectors to discover, open, trade, and own graded trading cards and collectibles.

Our products combine the excitement of opening packs with real ownership, instant buyback, a marketplace, and physical redemption. Our mobile app is the heart of this experience for collectors around the world.

We are a small, fast-moving team. Engineers at GACHA do more than complete tickets: they understand the customer, contribute to product decisions, ship quickly, study the results, and keep improving the experience.

The Role

We are looking for a product-minded mobile app developer with experience building and shipping production-level consumer mobile apps.

You will own the product end to end, with full agency to understand the user problem, design the experience, make product and technical decisions, implement the solution, launch it, measure the result, and iterate. This ownership model dramatically accelerates execution and avoids the context and coordination tax that slows other teams down.

You should care as much about whether an experience is intuitive, delightful, and commercially effective as whether the code is technically sound.

This is an AI-native engineering role. We expect you to use AI deeply throughout your workflow to explore solutions, understand unfamiliar code, generate and refactor implementation, write tests, investigate bugs, review changes, and improve your own development process. The goal is not simply to write code faster; it is to increase the scope, quality, and pace of what one strong engineer can own.

What You’ll Work On

• Build and improve GACHA’s production consumer mobile app, from the first interaction through the most complex transactional journeys.
• Own critical journeys including onboarding, pack discovery, purchasing, pack opening, wallet and payment flows, instant buyback, marketplace activity, and card redemption.
• Turn product ideas, customer problems, and rough concepts into thoughtful, shippable mobile experiences.
• Design the user experience and implement the technical solution yourself, with full ownership from idea to production.
• Work across the stack when needed to deliver a complete experience.
• Collaborate directly with founders, backend, operations, and customer support while remaining the clear owner of the product outcome.
• Improve product quality, responsiveness, performance, reliability, and accessibility.
• Instrument features and use product analytics, user feedback, and support issues to understand whether they are working.
• Run experiments and iterate based on user behavior rather than treating launch as the finish line.
• Identify friction, bugs, and product opportunities proactively instead of waiting for a detailed specification.
• Contribute to the technical foundations that allow the team to ship quickly without sacrificing stability.

What “AI-Native” Means at GACHA

You should already use AI coding tools as a core part of how you work. We are looking for someone who can:

• Break a product problem into clear tasks that can be effectively executed with AI assistance.
• Give AI agents the right context, constraints, and acceptance criteria.
• Use AI to navigate and understand an existing codebase, not only to generate isolated snippets.
• Parallelize implementation, debugging, testing, documentation, and code review where appropriate.
• Critically review AI-generated work for correctness, security, maintainability, and product quality.
• Build reusable prompts, workflows, scripts, and internal tools that improve the entire team’s velocity.
• Recognize when AI is accelerating the work and when direct engineering judgment is required.
• Demonstrate a meaningful increase in personal output without lowering the quality bar.

We care about the results of your AI workflow—not which particular tools you use.

What We’re Looking For

• At least 2 years of hands-on experience building and shipping production consumer mobile apps used by real customers.
• Strong mobile development experience, ideally with React Native and TypeScript, including taking apps through testing, release, monitoring, and ongoing iteration.
• Strong product sense and interaction-design judgment: you can turn an ambiguous user problem into a simple, polished experience without waiting for a detailed specification or handoff.
• Ability to take an ambiguous problem and independently drive it toward a shipped solution.
• Comfortable working across frontend, mobile, APIs, analytics, and backend systems when necessary.
• A track record of shipping quickly, learning from real users, and iterating.
• Strong understanding of mobile application architecture, state management, API integration, offline and error states, testing, performance, observability, and App Store release workflows.
• Experience integrating payments, authentication, notifications, analytics, or other third-party services.
• High ownership and clear communication, including communicating plans, tradeoffs, risks, and progress before being asked.
• Comfort working in a startup environment where priorities can change and engineers participate in product decisions.
• Genuine curiosity about AI-assisted software development and evidence that you are already using it effectively.

Nice to Have

• Experience building marketplaces, gaming, collectibles, fintech, e-commerce, or other transaction-heavy consumer products.
• Experience with mobile payments, wallets, in-app purchase flows, or complex checkout systems.
• Experience with experimentation, retention, growth engineering, or conversion optimization.
• Experience with product analytics tools such as PostHog, Amplitude, or Mixpanel.
• Familiarity with over-the-air mobile updates, App Store releases, and mobile observability.
• Interest in Pokémon, One Piece, sports cards, TCGs, sneakers, or collectibles.

What Success Looks Like

Within your first few months, you will:

• Develop a strong understanding of GACHA’s customers and core product journeys.
• Independently design, build, ship, and iterate on meaningful improvements to the mobile app.
• Reduce friction in important activation, purchase, and retention flows.
• Use data and customer feedback to explain the impact of your work.
• Improve the team’s development speed through effective AI workflows and better engineering systems.
• Become someone the team trusts to take an important product problem from idea to measurable outcome.

You’ll Thrive Here If

• You naturally think in terms of user problems and business outcomes, not just engineering tasks.
• You would rather ship, observe, and improve than spend weeks perfecting a plan in isolation.
• You notice broken or confusing experiences and feel compelled to fix them.
• You can balance speed with sound technical judgment.
• You communicate clearly and surface blockers early.
• You want full agency to shape the product experience and implement the technical solution yourself.
• You enjoy broad ownership and do not need every task to be fully specified.
• You believe AI is changing how high-performing product teams build software—and you are actively adapting how you work.