Senior Backend Engineer

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Senior Backend Engineer designing and building backend systems for AI-powered financial workflows at Semiotic Labs. Working on backend services, APIs, and integrations in a collaborative team environment.

Posted 5/26/2026full-timeRemote • California, New York • 🇺🇸 United StatesSeniorWebsite

Tech Stack

Tools & technologies

Distributed SystemsPostgresPythonReactRedisTypeScript

About the role

Key responsibilities & impact

Design, build, and maintain scalable async backend services and APIs in Python.
Own core systems end-to-end: architecture, implementation, testing, deployment, and operational excellence.
Build systems for multi-tenant workflows, fine-grained permissions, integrations, and agent-driven product experiences.
Write and review database migrations and row-level security policies in a compliance-sensitive environment.
Improve reliability, observability, and performance across critical paths.
Collaborate closely with product, design, and research to translate user needs into robust backend architecture.
Contribute to engineering standards, code review culture, and team ways of working.
Help shape technical direction in a fast-moving environment with evolving product requirements.

Requirements

What you’ll need

5+ years of professional software engineering experience with substantial backend development experience.
Strong production experience building backend services in Python.
Strong experience with asynchronous programming in Python, such as asyncio, async database access, or high-concurrency service development.
Deep PostgreSQL experience, including schema design, query tuning, transactions, and production migrations.
Experience designing or implementing multi-tenant data isolation and access control.
Strong software design fundamentals: modular architecture, testing discipline, maintainability, and clear interface design.
Experience with Redis or similar infrastructure for caching, queues, rate limiting, or pub/sub.
Ability to independently own projects and make sound technical tradeoffs in ambiguous environments.
Strong communication skills and a collaborative, low-ego working style.
Strongly preferred: Experience with FastAPI, Starlette, Litestar, or another modern Python web framework.
Experience building backend systems for AI products, agentic workflows, or LLM-powered applications, such as RAG pipelines, tool-calling agents, or orchestration layers.
Experience with security-sensitive or enterprise systems, including access controls, audit logging, and compliance-driven engineering constraints.
Experience with OpenTelemetry or comparable production observability tooling.
Nice to have: Experience with pgvector, SurrealDB, or other vector retrieval systems.
Exposure to SOC 2, fintech, healthtech, or other regulated environments.
Experience with agent runtimes, sandboxing, or MCP integrations.
Familiarity with distributed systems, asynchronous processing, and performance optimization.
Startup or zero-to-one experience.
Comfort reading TypeScript or React during frontend-backend integration work.

Benefits

Comp & perks

Work on technically challenging products at the intersection of AI, security, and enterprise software.
Join a small, senior team with deep experience in research, distributed systems, and production engineering.
Have meaningful influence over architecture, product direction, and engineering culture.
Build products with real-world impact, not just prototypes.

ATS Keywords

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Applicant Tracking System Keywords

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Hard Skills & Tools

Pythonasynchronous programmingPostgreSQLRedisFastAPIStarletteLitestarOpenTelemetrydatabase migrationssecurity-sensitive systems

Soft Skills

strong communication skillscollaborative working styleindependent project ownershiptechnical tradeoffslow-ego working style