Open to opportunities

Allen Zhang

@allenzhang

Full-stack software engineer focused on secure, privacy-preserving identity platforms for large-scale public and consumer systems.

United States

Message

What I'm looking for

I’m looking to apply my privacy-focused, security-first full-stack foundation to privacy-preserving identity solutions—building secure platforms with strong correctness, accessibility, and deployment reliability for public sector partners and millions of end users.

I’m a full-stack software engineer with 8+ years delivering backend services and web applications in statically typed languages—primarily Java—across commerce, logistics, and high-compliance security environments. I translate complex requirements into production-ready systems that meet rigorous security, privacy, and accessibility standards.

Most recently, I built and shipped full-stack features at Toast, writing Java backend services and React/TypeScript frontends consumed by millions of users daily. I design and expose REST API endpoints with a strong emphasis on security, correctness, and accessibility, and I improve observability and deployment reliability on AWS using Docker and CI/CD to reduce release cycle time and production incidents.

Earlier, at Gopuff, I led full-stack delivery across microservices on AWS and GCP, designing REST API and GraphQL endpoints and optimizing PostgreSQL query performance for critical order-management services. I’m especially drawn to privacy-preserving identity solutions—grounded in my work supporting PKI/TLS and federal certification processes, plus my long-term interest in responsible data handling from my time building cognitive and eye-tracking systems.

Experience

Work history, roles, and key accomplishments

Current

Full-Stack Engineer

Current

Toast

Aug 2024 - Present (1 year 11 months)

Built and shipped full-stack features for a large-scale restaurant commerce platform, developing Java backend services and React/TypeScript frontends. Designed secure, accessible REST APIs and improved AWS deployment reliability using Docker and CI/CD, while mentoring junior engineers.

Java React TypeScript REST APIs Security Accessibility AWS Docker CI CD Observability Mentoring

Full-Stack Engineer

Gopuff

Jul 2021 - May 2024 (2 years 10 months)

Led full-stack development of backend services and web applications for instant-commerce and logistics workflows using Java and TypeScript. Built REST and GraphQL endpoints and improved order-management service throughput through PostgreSQL query and hot-path optimization, applying privacy-focused data handling.

Java TypeScript Microservices AWS GCP REST APIs GraphQL PostgreSQL Order Management Data Privacy

Backend Engineer

Auctane

Jan 2021 - Jun 2021 (5 months)

Developed backend services for shipping and logistics software, extending REST API integrations and platform capabilities. Implemented Java features with unit and integration testing, optimized PostgreSQL queries/models, and supported CI/CD pipeline reliability while collaborating on cross-functional delivery.

Java REST APIs Unit Testing Integration Testing CI CD PostgreSQL Query Optimization AWS Azure

Software Engineer

Senseye, Inc.

Jul 2018 - Dec 2020 (2 years 5 months)

Built software for cognitive and eye-tracking research products, implementing backend data processing pipelines and full-stack features. Owned backend work in Java and Python plus frontend web components with validation and accessibility considerations, including privacy-aware handling of sensitive biometric research data.

Java Python Data Processing Web Components Accessibility Data Privacy Open Source Contributions

Software Engineer Intern

Cisco

Jun 2017 - Aug 2017 (2 months)

Independently built a packet generation tool in Python that constructs custom packets, sniffs traffic on multiple interfaces, and sends concurrent, customizable L2/L3 streams. Emulated network devices using ARP/ICMP requests and responses to validate traffic flows with live statistics in a government-technology–adjacent environment.

Python Packet Generation Networking ARP ICMP Network Testing

Software Developer Intern

Ixia

Jun 2016 - Aug 2016 (2 months)

Contributed security features that helped the product obtain federal certification. Designed and developed a tool to automate custom TLS certificate generation following PKI standards, including a user-friendly configuration tool driven by WebAPI (REST API) requests.

Security Engineering PKI Certificate Automation Web APIs REST APIs