Software Development Engineer III

About Osto

Osto is a protection-first, all-in-one cybersecurity platform that makes startups enterprise-ready in minutes. We secure cloud, apps, APIs, devices, and data with real enforcement — no security engineer required.

Role Overview

We're hiring an SDE3 Backend Engineer (Go) to architect and build the core of Osto's security platform. You'll work directly with founders, own critical services end-to-end, and shape the technical foundation for a fast-moving cybersecurity product.

What You'll Do

• Own assigned backend services end-to-end: design implementation testing deployment monitoring.
• Collaborate with business, product, design, and frontend to ship features rapidly while maintaining strong engineering standards.
• Model complex security and infrastructure concepts (iam, endpoints, networks, cloud assets, risks etc) into clean domain models and data flows
• Improve code quality through reviews, technical design docs, and mentoring mid/junior engineers
• Own/Assist in increasing the adoption rate of your own built features.

What We're Looking For

• 4+ years of experience in backend / product engineering, with at least 3+ years working heavily with Go.
• Strong experience designing and building distributed systems, APIs, and event-driven or message-based architectures.
• Comfortable leading scoping, breaking down, and delivering complex projects independently (SDE3-level ownership).
• Have a voracious and intrinsic desire to learn and fill in missing skills and an equally strong talent for sharing learnings clearly and concisely with others
• Bonus: Experience in security products (WAF, EDR, CSPM, SIEM, scanners) or infra-heavy systems is a strong plus.

What's In It For You

• Build a mission-critical security platform used by high-growth startups and engineering teams.
• Work directly with founders, shape the architecture, and influence product and tech direction from the early days.
• High ownership, low bureaucracy, and a culture of rapid iteration and pragmatic engineering.
• Clear path to grow into Staff Engineer / Architect / EM as the product and team scale.