Staff Fullstack Engineer

Who We Are:

Alpaca is a US-headquartered, global leader in agent-first brokerage infrastructure for stocks, ETFs, options, crypto, fixed income, 24/5 trading, and more. Amongst our subsidiaries, Alpaca is a licensed financial services company, serving hundreds of financial institutions across 40 countries with our institutional-grade APIs. This includes broker-dealers, investment advisors, wealth managers, hedge funds, and crypto exchanges, totalling over 10 million brokerage accounts. Our global team is a diverse group of experienced engineers, traders, and brokerage professionals who are working to achieve our mission of opening financial services to everyone on the planet. We're deeply committed to open-source contributions and fostering a vibrant community, continuously enhancing our award-winning, developer-friendly API and the robust infrastructure behind it. Alpaca is proudly backed by $400 million in funding from top-tier global investors including Portage Ventures, Spark Capital, Tribe Capital, Social Leverage, Horizons Ventures, Opera Tech Ventures, SBI Group, Derayah Financial, Unbound, Peak XV, Elefund, and Y Combinator. Our Team Members:

We're a dynamic team of 400+ globally distributed members who thrive working from our favorite places around the world, with teammates spanning the USA, Canada, Japan, Hungary, Nigeria, Brazil, the UK, and beyond! We're searching for passionate individuals eager to contribute to Alpaca's rapid growth. If you align with our core values—Stay Curious, Have Empathy, and Be Accountable—and are ready to make a significant impact, we encourage you to apply.

About the Role

We are seeking a Staff Full Stack Engineer to lead the technical direction of the team that builds Alpaca's Trading API product. Trading API serves developers, traders, and institutions who trade directly with Alpaca. The team owns that customer experience end to end: how customers access the platform, how their accounts are structured and secured, and the applications they use to trade.

The work spans the stack: customer-facing trading applications, the identity, account, and permission systems behind them, and integrations for partner apps and AI agents. The team also builds customer-facing trading features end to end, across our API.

This is a high-trust domain. These systems decide who can act on an account and what they are allowed to do. A defect can expose customer data, let the wrong person place a trade or move money, or lock a customer out at the moment they need to trade. The customer-facing surfaces also carry real-time trading: an order ticket or positions view that shows stale or wrong data can lead to a bad trade. We are looking for an engineer who has built and owned systems like this — identity and authorization, account models, and trading or financial applications — and who is as comfortable designing an authorization model as shipping the interface built on top of it.

You will not manage people directly. You will lead through architecture, code, design reviews, and mentorship, and you will remain a principal contributor. You will be the senior technical anchor for the team, partnering with the engineering manager, Product, and Design, and working closely with the trading, margin and risk, and platform teams behind the API.

Key Responsibilities

Own the architecture and technical roadmap for how customers access and use Trading API: identity and authentication, authorization and permissions, account and sub-account models, partner OAuth, and customer-facing trading and account-management applications.

Design the access model for increasingly complex account structures — multiple users per account, sub-accounts, entity and advisor accounts, and delegated API and agent access — so that permissions are explicit, auditable, and enforced on the server.

Lead technical delivery of next-generation Trading API customer applications, including real-time market data, order entry, and positions and order views, as the product expands to new customer surfaces.

Drive the move from legacy monolith endpoints to a dedicated application backend, with clear API contracts between customer applications and platform services such as trading, accounts, transfers, ledger, and market data.

Set the security bar for customer-facing systems: session and credential handling, MFA and passkeys, OAuth flows, rate limiting, input validation, and fast, durable responses to security findings.

Set the standard for safe delivery: feature flags, staged rollouts, preview environments, testing strategy, and production observability.

Partner with Product, Design, Compliance, Security, Brokerage Operations, and adjacent engineering teams to define behaviour and integration boundaries.

Lead design reviews, mentor senior and mid-level engineers, and raise the engineering bar as the team grows.

Act as a technical point of escalation for production issues on customer-facing Trading API systems, and drive durable prevention after incidents.

Qualifications

8+ years of software engineering experience, with significant time on both backend services and customer-facing applications. Evidence of scope and ownership matters more than a strict year count.

Proven ownership of a production system where a defect could expose customer data, grant the wrong access, or cause financial loss.

Deep experience with authentication and authorization: OAuth 2.0 and OpenID Connect, session and token management, MFA, and role- or attribute-based permission models.

Strong backend expertise in Go, or deep experience in Java, Kotlin, C#, or Rust and a clear willingness to work primarily in Go.

Strong frontend experience with TypeScript and React, including complex, state-heavy applications. Experience with real-time data over WebSockets or other streaming protocols is strongly preferred.