Senior Full-Stack Engineer - TypeScript/Node.js React Native (LATAM Remote, Contract)

Job description

About LiveLineIQ

LiveLineIQ is an early-stage startup building a real-time sports betting intelligence product. The app is currently in closed testing, with a public launch targeted for late summer.

The platform ingests live odds and game-state data, applies statistical analysis to identify potential betting edges, and surfaces timely opportunities to users through a mobile-first experience.

We are looking for a senior engineer who can help the team move faster across backend/API work, data-driven product workflows, and mobile/frontend execution over the next couple of months.

About the Role

We are looking for a senior full-stack engineer to work directly with our technical lead and founding team.

This person should be comfortable contributing across an existing TypeScript / Node.js API layer, backend data workflows, and mobile/frontend surfaces as needed. The ideal candidate can make incremental improvements to an established codebase, debug issues across the stack, clarify technical requirements, and ship reliable backend and frontend changes with limited hand-holding.

The initial focus will be helping the team move faster across backend/API work, data-driven product workflows, and mobile/frontend execution. This includes making incremental changes to an established TypeScript / Node.js API layer, working with live odds and game-state data, supporting API integrations, and contributing to React Native/mobile UI work where needed.

This is not a pure data engineering role, but comfort working around backend data flows, APIs, and real-time or event-driven systems is important.

Please note:

• This is an immediate project need. Candidates should be available to interview right away and onboard shortly after selection.
• This is an initial 8-week fractional / part-time contract role, with weekly hours expected to be around 12-15 hours per week.
• Potential to extend or increase hours based on project / client demand.

What You’ll Do

• Make incremental improvements to an established TypeScript / Node.js API layer.
• Work with backend services that support live odds, game-state data, alerting logic, and user-facing product workflows.
• Help debug and improve API integrations between backend systems and mobile/frontend surfaces.
• Contribute across backend, data-adjacent workflows, and React Native/mobile UI as needed.
• Identify and resolve bugs across the stack, including API, data flow, and frontend/mobile issues.
• Work with APIs that support real-time odds, game-state data, and alerting workflows.
• Build and refine user-facing features across mobile and potentially web.
• Support iOS TestFlight and Android Play Console testing/release processes when needed.
• Collaborate with the technical lead on architecture, implementation, and release readiness.
• Review, improve, and ship code in an AI-assisted development environment.
• Help identify bugs, edge cases, and launch blockers before public release.

What We’re Looking For

• Strong TypeScript experience across backend and frontend codebases.
• Experience working with Node.js APIs or similar backend API layers.
• Comfortable making incremental changes to an established backend codebase.
• Ability to work with REST APIs, backend services, data flows, and real-time or event-driven product logic.
• Experience debugging issues across backend, API, and frontend/mobile surfaces.
• Experience contributing to React Native or mobile/frontend applications, ideally in a production environment.
• Experience with both iOS and Android mobile development workflows is helpful.
• Comfort working with Expo / EAS, TestFlight, and Google Play Console preferred.
• Experience building or supporting applications hosted on AWS.
• Strong independence and ability to execute with limited guidance.
• Experience working in early-stage startups or ambiguous technical environments.
• Clear communication and ability to clarify requirements, raise blockers, and recommend practical implementation approaches.
• Comfortable working independently in a fractional/contract capacity.
• Experience using AI coding tools such as Claude Code, Cursor, GitHub Copilot, or similar tools.
• Ability to critically review AI-generated code and avoid shipping low-quality or unmaintainable output.
• High discretion when working with proprietary product logic, algorithms, and sensitive project materials.

Nice to Have

• Experience with sports betting, odds, trading, financial markets, or real-time alerting products.
• Experience with low-latency or time-sensitive consumer applications.
• Experience building subscription, notification, or alert-based mobile products.
• Familiarity with backend/data pipelines, analytics, or statistical model outputs.
• Experience building serverless applications.
• Experience with AWS services such as Lambda, API Gateway, DynamoDB, S3, Cognito, CloudWatch, or similar.
• Experience working with real-time data feeds, event-driven systems, or data-heavy APIs.
• Experience supporting React Native apps built with Expo / EAS.
• Experience working with non-technical founders or translating loose requirements into technical implementation.

Tech / Product Context

Current product environment includes:

• TypeScript
• Node.js API layer
• React Native mobile app
• Expo / EAS
• iOS TestFlight
• Android Play Console closed testing
• Web and mobile product surfaces
• APIs supporting live odds, game-state data, and alerting logic
• AWS-hosted application environment
• AI-assisted development workflow using tools such as Claude Code

The core product already has a technical lead in place, and the data backbone is being led internally. This role is intended to add engineering capacity across the backend/API layer, data-driven product workflows, and mobile/frontend surfaces so the team can move faster ahead of launch.

Company
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