Senior Fullstack Engineer — Authentication Platform

Remote | Europe & North America Preferred

Build the Security Infrastructure Powering Global Investing

Have you built and operated scalable backend services while delivering modern frontend applications?

Do you enjoy solving engineering challenges around security, authentication, high availability and distributed systems?

Have you worked on systems serving millions of users, handling thousands of requests per second or supporting mission-critical applications?

Would you like to help rebuild the authentication infrastructure powering investing platforms around the world?

If so, we'd love to speak with you.

About Alpaca

Alpaca is a global brokerage infrastructure company powering investing products for fintechs, banks, brokerages and trading platforms worldwide.

Our APIs and platforms support over 10 million brokerage accounts across 40+ countries, providing access to stocks, ETFs, options, crypto, fixed income and more.

Backed by over $430 in funding, we're building the global infrastructure layer for investing.

The Opportunity

We're looking for a Fullstack Engineer to join our Platform Authentication team and help build the systems that secure access to Alpaca's products, applications and APIs.

Our Authentication team is responsible for ensuring that customers, partners and employees can securely access the right products and services through authentication, authorization and identity-provider infrastructure.

We're currently modernizing our authentication platform, replacing legacy systems, standardizing authentication across products and preparing our infrastructure for global, multi-region operations.

Our services already handle approximately 15,000 requests per second, and we're solving complex challenges around security, scalability, resilience and high availability.

You'll join a small engineering team with significant ownership across backend services and frontend applications, helping design, build, deploy and operate the infrastructure that powers secure access across Alpaca.

We believe in engineers owning outcomes, not just tickets.

What You'll Be Working On

• Authentication Platform: Design and build authentication and authorization services securing Alpaca's products and APIs.
• Platform Modernization: Help replace legacy authentication systems and migrate identity providers toward a centralized Keycloak-based solution.
• Multi-Region Infrastructure: Build secure, highly available services capable of operating reliably across multiple geographical regions.
• Fullstack Development: Build and maintain login, user management, permissions and credential-management interfaces.
• High Availability & Reliability: Design resilient systems using caching, service independence and fault-tolerant architecture.
• Developer Platform: Help develop shared libraries, SDKs and developer-facing infrastructure that make integrating with Alpaca easier.
• End-to-End Ownership: Take projects from architecture and implementation through deployment, monitoring and production support.

Tech Stack

• Backend: Go, REST APIs, gRPC
• Frontend: React, TypeScript
• Database: PostgreSQL
• Authentication: Keycloak, OAuth 2.0, OpenID Connect, JWT
• Infrastructure: Kubernetes, Helm
• Additional Technologies: Java, Kafka/Redpanda, Grafana

What We're Looking For

• 5+ years of software engineering experience, ideally within product-focused or high-growth technology companies.
• Strong backend engineering skills, with experience designing, building and operating production services.
• Hands-on React and TypeScript experience, with the ability to independently deliver frontend features.
• Experience building scalable, reliable applications and working with relational databases.
• Strong understanding of software architecture, API development and production engineering.
• Engineers who enjoy taking ownership from initial requirements through deployment and ongoing operation.
• Comfortable working autonomously within a small, collaborative and globally distributed engineering team.
• An interest in authentication, security and building reliable platform infrastructure.

Bonus Points

• Experience with authentication, authorization or identity and access management.
• Knowledge of OAuth 2.0, OpenID Connect, SAML or JWT.
• Experience integrating with Keycloak, Okta, Cognito or other identity providers.
• Experience building high-availability or multi-region distributed systems.
• Production experience with Go/Golang.
• Familiarity with Kubernetes, Helm or cloud-native infrastructure.
• Experience with role-based access control, API security or developer platforms.

You don't need to be an authentication specialist or already know Go. We're equally interested in strong fullstack engineers who are excited to develop expertise in this domain.

Why Join Alpaca?

• Build Critical Infrastructure. Work on the authentication systems securing access to a global brokerage platform used by millions of investors.
• Solve Meaningful Engineering Challenges, tackle real problems involving high availability, multi-region architecture, platform modernization and security.
• Significant Engineering Ownership
• Join a small team where your technical decisions and contributions will have a direct impact on the platform, work across the Full Stack
• Own backend services and frontend functionality, with opportunities to influence architecture, reliability and developer experience.
• Fully Remote, Globally Distributed, collaborate with talented engineers across different countries and time zones, with the autonomy to do your best work.

Location & Compensation

Alpaca is a fully remote company. For this opportunity, we're particularly interested in candidates based in Europe and North America.

In addition to competitive compensation, Alpaca offers equity, comprehensive benefits and the opportunity to help build the infrastructure powering the future of global investing.