Software Engineer, Foundations Team

Hex Technologies•San Francisco, CA

8h•$215,000 - $270,000

About The Position

About the team The Foundations team builds and evolves the application-level infrastructure that powers Hex. We own the shared backend systems, frameworks, and primitives that other teams depend on—helping the company move faster while maintaining reliability, performance, and security. Our work spans APIs, realtime transport, storage frameworks, background processing, and internal tooling. Rather than shipping isolated features, we focus on creating durable systems that scale with the company and make product development easier for everyone. About the role We’re looking for a Senior Backend Software Engineer to help design, maintain, and evolve the core systems used across Hex. This role is centered on backend architecture and shared infrastructure, with responsibility for APIs, realtime communication, data access frameworks, job orchestration, and internal admin tooling. You’ll work closely with product engineering teams to understand their needs, then turn common patterns into robust, reusable systems. You’ll help define standards, influence architecture, and raise the quality bar across the backend. Frontend experience is helpful for understanding end-to-end workflows, but this role is primarily backend-focused. Core Contributions You will help contribute to and evolve several foundational areas, including: APIs GraphQL (schema design, performance, developer ergonomics) Authentication & authorization (security, scalability, correctness) Multiplayer & collaboration APIs (realtime state, concurrency) Transport WebSockets and realtime communication infrastructure Storage Frameworks Postgres (schema design, query optimization, migrations) S3, DynamoDB, Redis Job & Workflow Systems BullMQ and background job processing Temporal or similar workflow orchestration systems Internal Tooling Internal admin tools for debugging, operations, and customer support

Requirements

5+ years of professional software engineering experience with a strong backend focus
Experience working with Typescript/Node.js and SQL
Experience building and maintaining shared backend systems or frameworks used by multiple teams
Strong understanding of API design, distributed systems, and asynchronous workflows
Experience working with relational databases and data modeling at scale
Familiarity with background job systems, queues, or workflow orchestration tools
Comfort operating and evolving production systems over time
Experience with cloud infrastructure (AWS preferred)
Strong communication skills and a collaborative, leverage-oriented mindset

Nice To Haves

Experience with Python
Hands-on experience with GraphQL, WebSockets, BullMQ, or Temporal
Familiarity with observability tooling (metrics, tracing, logging)
Background in data platforms, developer tools, or collaborative systems
Experience with frontend technologies (e.g. React, TypeScript) for end-to-end context
Open-source contributions, especially in backend or infrastructure projects

Responsibilities

Design and build backend frameworks and services used across the company
Own and evolve critical shared systems, including APIs, realtime transport, and job orchestration
Improve reliability, performance, observability, and security of foundational backend infrastructure
Partner with product teams to turn recurring needs into shared abstractions
Lead technical design discussions and help set architectural direction
Drive refactors, migrations, and system upgrades that reduce long-term complexity
Improve internal tooling to support debugging, operations, and customer-facing workflows
Mentor other engineers and contribute to strong engineering standards and practices