Backend Engineer — Confidential AI Security Startup

Aionia; San Francisco (CA); Hybrid; USD 135,000 - 250,000; Full time

Job summary

Aionia is seeking a Backend Engineer to build and own production-facing backend services for their human risk platform. You will play a key role in ensuring the reliability, scalability, and performance of critical systems in a fast-paced hybrid environment.

The role demands experience in backend software development, API building, and integration with cloud systems like AWS. With a competitive salary range of $135,000 – $250,000, this is an opportunity to contribute directly to Aionia's growth.

Qualifications

• 3+ years of experience developing backend software.
• Designed and owned production‑facing services end‑to‑end.
• Experience at high‑growth or successful startups.

Responsibilities

• Design, implement, and own backend services for the human risk platform.
• Drive reliability and scalability of backend systems.
• Integrate with external APIs and data pipelines.

Skills

Backend software development

Scalable backend systems

API development

Data pipelines

Cloud infrastructure

Tools

AWS

Terraform

PostgreSQL

EKS

Job description

Backend Engineering · Production Ownership

Backend Engineer

Build the platform. Own production.

Confidential AI Security Startup · San Francisco, CA · Hybrid

San Francisco · Hybrid (3 days/week) Full-time · In-Office 3 Days/Week $135,000 – $250,000 + RSUs $31M Raised · ~55 Employees No Visa Sponsorship

About the Company

This is a confidential AI-driven human risk platform that directly shapes employee behavior inside enterprise organizations. Founded by alumni of a category-defining cybersecurity company and incubated by a top-tier venture firm before the raise closed, the company has secured $31M from two marquee investors.

The platform ingests complex employee behavioral data, processes it in real time, and deploys automated interventions at the point of risk. With a team of ~55 drawing from top-tier tech companies and leading CS programs, engineering density here is unusually high for the stage.

Founded by alumni of a multi-billion-dollar security exit. Backed by the same investors who backed them.

The company was incubated inside one of the venture firms that backed it before the raise — a path reserved for a very small number of founding teams. The founders bring direct pattern-matching experience on how to build a category-defining security platform at scale.

The Opportunity

This is a hands‑on backend engineering role building production‑facing services that power the human risk platform. You will design, implement, and own systems that ingest behavioral data, process it in real time, and trigger automated interventions — the data infrastructure here is the product, not a supporting function.

The company is experiencing explosive growth and sales close enterprise deals faster than engineering can keep up. The line between what you build and company growth is direct and measurable.

Data is the product, not a side function — and engineering is the bottleneck. The decisions you make will directly shape whether this company can scale to serve the world's largest enterprises.

What You'll Do

• Design, implement, and own production‑facing backend services that power the human risk platform
• Take ownership of backend systems and drive reliability, scalability, and maintainability at startup speed
• Work closely with product and engineering teams to translate customer requirements into durable platform designs
• Build and integrate with external APIs, relational DB backends, ETL/data pipelines, or distributed systems
• Contribute to cloud infrastructure using AWS, Terraform, and EKS
• Make thoughtful technical tradeoffs and build systems that anticipate evolving needs as the company scales

Requirements

• 3+ years of experience developing backend software
• Designed, implemented, and owned production‑facing services end‑to‑end
• Track record of building reliable, scalable backend systems
• Experience at high‑growth or successful startups
• Built APIs, data pipelines, or distributed systems
• Owned production‑facing backend services end‑to‑end — not just contributed to
• High‑trajectory individual contributor with strong growth mindset
• Thrives in fast‑paced, ambiguous startup environments independently

Nice to Have

• Experience building ETL and data pipelines
• Experience with relational DB backends (Django / PostgreSQL)
• Experience with AWS, Terraform, EKS, and cloud systems
• Experience building distributed systems and backends
• Experience building and integrating with external APIs

Traits to Avoid

• 10+ years / staff‑level background — focus is mid‑level, high‑growth builders
• Candidates without end‑to‑end production ownership (contributors only)
• Process‑heavy or large‑enterprise‑only background with no 0→1 startup experience
• AI/ML‑focused engineers without strong backend systems fundamentals
• Candidates not available for hybrid on‑site in SF (3 days/week non‑negotiable)