Senior Backend Architect: APIs, Real-time, Equity

Mosaic.tech; San Francisco (CA); On-site; USD 215,000 - 270,000; Full time

Job summary

Hex is hiring a Senior Backend Software Engineer to design and evolve core systems used across our platform. You will own APIs, realtime transport, data access frameworks, and job orchestration, leaning into scalable, secure backend infrastructure.

You'll collaborate with product teams to turn recurring needs into shared abstractions, drive architectural direction, and mentor others while improving reliability, performance, and observability.

Qualifications

• 5+ years of professional software engineering experience with a strong backend focus.
• Experience 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 with relational databases and data modeling at scale.

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.

Skills

5+ years background

Typescript/Node.js

SQL

APIs

Distributed systems

Relational databases

AWS

Communication

Tools

GraphQL

WebSockets

BullMQ

Temporal

Postgres

Redis

Kubernetes

Terraform

Helm

Express

Job description

Hex is hiring a Senior Backend Software Engineer to design and evolve core systems used across our platform. You will own APIs, realtime transport, data access frameworks, and job orchestration, leaning into scalable, secure backend infrastructure.

You'll collaborate with product teams to turn recurring needs into shared abstractions, drive architectural direction, and mentor others while improving reliability, performance, and observability.