Senior Backend Software Engineer

Role Summary

You’ll build the backend systems that power Twenty’s cyber and electromagnetic capabilities—software that ingests real-time operational signals, models complex relationships, and serves high-throughput APIs at machine speed. You’ll design and ship reliable services in Go, working with known-hard problems like graph data modeling, event-driven architectures, and performance ’ll partner closely with product, frontend, and domain experts to turn operator needs into durable platform capabilities.

This role spans both cloud and on-premises environments supporting mission‑critical U.S. national security outcomes.

• You care about building systems that have real‑world impact, especially in national security and defense of democracies.
• You’re excited by hard backend problems: throughput, latency, correctness, and operability under pressure.
• You take pride in clean interfaces—APIs that are intuitive, consistent, and built to evolve.
• You think in systems: data models, services, and workflows that work together reliably.
• You’re pragmatic and iterative—ship value quickly, then harden, measure, and improve.
• You collaborate well across disciplines, communicate clearly, and welcome direct feedback.
• You default to ownership: you notice gaps, propose solutions, and drive them to completion.

• Design and implement scalable backend services in Go that improve operator decision‑making and response.
• Build high-performance APIs that power customer‑facing workflows and internal platform capabilities.
• Model complex relationships in graph databases and optimize schemas and queries for speed and clarity.
• Implement event-driven systems (e.g., with NATS) to process real-time operational data streams.
• Develop and maintain automated tests to protect correctness, security, and performance as the system evolves.
• Build and operate microservices deployed on AWS, with an eye toward resilience and cost‑aware scaling.
• Create and improve CI/CD pipelines that enable fast, secure delivery of new capabilities.
• Partner with cyber operations experts to translate domain needs into robust product features.
• Collaborate with frontend engineers on API contracts and data structures that are efficient and usable.
• Evaluate new technologies and patterns that could unlock better operational outcomes.

• You have 5+ years of professional software development experience building backend (or full‑stack) applications.
• You have strong proficiency with Go (Golang) and have shipped production services with it.
• You have experience working with graph databases (Neo4j, AWS Neptune, or similar), including schema design and query performance.
• You have working knowledge of event-driven architectures and message queues/streaming systems.
• You have experience building and maintaining APIs (REST and/or GraphQL).
• You have experience with cloud infrastructure, ideally AWS, and understand cloud-native deployment patterns.
• You have hands‑on experience with containerization and microservices architectures.
• You have a strong foundation in secure coding practices and can reason about security tradeoffs.
• You have a bachelor’s degree in Computer Science, Software Engineering, or a related field, or equivalent practical experience.

• You’ve delivered software in defense, security, or other mission‑critical environments.
• You’ve built systems for analysts, operators, or high‑tempo users where speed and reliability matter.
• You’ve integrated AI/ML capabilities into production systems (inference, pipelines, or tooling).
• You have experience with large‑scale data processing and analytics workloads.
• You’ve contributed meaningfully to open-source projects.
• You’ve used observability tooling (metrics, tracing, logging) to debug and improve production systems.

• Go (Golang), GraphQL/REST
• Graph databases (Neo4j, AWS Neptune) and complex graph schemas
• NATS and event-driven architectures
• AWS, microservices, containers
• CI/CD pipelines, automated testing frameworks, infrastructure-as-code patterns
• Monitoring and observability tools

• Health: medical, dental, and vision plan options. Life / AD&D, disability coverage options.
• Family:…