Lynx Capital Partners

Responsibilities

• Market data: ingest vendor feeds, normalize instruments and symbology, and fan out to web and mobile clients over WebSockets (subscription management, snapshot + delta, conflation and throttling, slow-consumer handling, reconnect and resync); enforce entitlements (real-time vs. delayed, professional vs. non-professional).
• Order management: build the integration layer on top of the clearing firm's REST and FIX APIs — order gateway (validation, pre-trade checks, idempotent submission), order state driven by provider events, positions, realized and unrealized P&L, reconciliation against snapshots and the ledger.
• Reliable ingestion of provider webhooks and event streams: signature verification, deduplication, out-of-order handling, gap detection, replay.
• Authentication and session management, account lifecycle, entitlements, and billing hooks.
• Identify gaps in vendor APIs and propose solutions (build, work around, or escalate to the vendor). Design for graceful degradation when upstream feeds are unavailable.

Requirements

• 5+ years of backend development with a focus on distributed, event-driven systems; 3+ in Node.js / TypeScript, including the runtime under load (event loop, stream backpressure, memory/GC, scaling stateful connections).
• Has built and operated a high fan-out real-time system serving many concurrent clients and can describe it in numbers (connections, messages per second, p99 latency).
• Practical understanding of message ordering, duplicate delivery, idempotency, retries, backpressure, replay, and failure recovery.
• Experience running production systems that handle financial transactions; experience with monitoring, structured logging, tracing, and incident investigation.
• Experience with AWS (containers, IAM, managed messaging/streaming) and Redis; infrastructure-as-code.
• Strong automated-testing practices (unit, integration, end-to-end).
• Occasional traveling to the USA might be needed. 

Nice to have

• Brokerage, clearing, custody, or market-data provider integrations; knowledge of equity and options order lifecycles (submission, partial fills, cancel/replace, rejection).
• FIX, financial instrument symbology, exchange connectivity.
• PostgreSQL, Redis, and a time-series or analytical store.
• Systems handling monetary values, audit trails, reconciliation, regulatory requirements.
• Futures, crypto, or prediction-market platforms.

Responsibilities

• Build and maintain the trading application in React Native / Expo with TypeScript: onboarding and identity verification, funding, watchlists, quotes and charts, order entry, positions and P&L, options chains.
• Consume streaming market data over WebSockets: subscription management, reconnect and resynchronization, smooth rendering under high-frequency updates.
• Implement authentication (MFA, biometric unlock), secure token storage, deep linking, push notifications, and third-party SDK integrations (bank linking, identity verification).
• Work with the product designer and backend engineers on feature design and delivery.
• Own builds, store submissions, over-the-air updates, and App Store / Google Play releases; monitor crashes and performance in production.

Requirements

• 5+ years of mobile development; 3+ years with React Native, including at least one consumer app shipped to both stores.
• Strong TypeScript and modern React; experience with Expo tooling (routing, builds, config plugins).
• Experience building real-time, high-frequency mobile interfaces; practical understanding of React Native performance (rendering, JS/UI threads, memory, list virtualization).
• Experience implementing OAuth/MFA/biometrics and integrating native SDKs.
• Solid automated-testing and production-monitoring practices.
• Comfortable making product decisions in a small team without detailed specifications.
• Occasional traveling to the USA might be needed

Nice to have

• Trading or brokerage applications, order books, financial order types.
• Charting libraries, animation/gesture and rendering libraries, E2E mobile test frameworks.
• Native iOS or Android experience (Swift or Kotlin).

Why we are hiring

We need a full-stack developer to build and maintain our web-based brokerage platform. The person will work across the product—from customer-facing React interfaces to backend services, integrations, and cloud infrastructure.

What the person will own

• Product development

1. Build React experiences for onboarding, account management, trading, funding, and portfolio management.
2. Develop backend services and APIs supporting the platform.
3. Integrate external brokerage, payments, KYC, authentication, and other third-party services.

• Platform and infrastructure

1. Design secure and scalable services using TypeScript, Node.js, MongoDB, and AWS.
2. Deploy and operate containerized workloads using ECS and Fargate.
3. Manage cloud infrastructure using Terraform.

4. Monitor production systems and investigate performance and reliability issues.

    

Level and experience

• 5+ years of professional full-stack development experience.
• Strong production experience with TypeScript, React, and Node.js.
• Experience building and operating customer-facing web products.

• Ability to own features from product requirements through deployment and production support.

   

Must-have skills

• Strong proficiency in React, TypeScript, and Node.js.
• Experience designing REST APIs and integrating external services.
• Production experience with MongoDB, including data modelling and query optimization.
• Understanding of authentication platforms such as Clerk, Auth0, or Cognito.
• Knowledge of OAuth 2.0, OpenID Connect, JWTs, sessions, MFA, and role-based access control.

• Experience with automated testing, CI/CD, monitoring, and incident investigation.

   

Nice-to-have skills

• Strong AWS experience, particularly ECS, Fargate, IAM, CloudWatch, and networking.
• Experience managing infrastructure with Terraform.
• Experience with brokerage, trading, fintech, payments, or KYC products.
• Familiarity with WebSockets and real-time applications.

• Experience handling financial data, audit trails, and reconciliation.

   

Tech stack

• Frontend: React, TypeScript
• Backend: Node.js, TypeScript
• Database: MongoDB
• Authentication: Clerk, OAuth 2.0, OpenID Connect
• Cloud: AWS, ECS/Fargate, IAM, CloudWatch
• Infrastructure: Terraform, Docker
• Delivery: CI/CD and automated testing