Senior Backend Software Engineer

The role

You will build backend systems that power cyber and electromagnetic capabilities. You will design and ship reliable services in Go, working with graph data modeling, event-driven architectures, and high-throughput APIs.

What you will do

• Design and implement scalable backend services in Go.
• Build high-performance APIs for customer-facing workflows and internal platform capabilities.
• Model complex relationships in graph databases and optimize schemas and queries.
• Implement event-driven systems to process real-time operational data streams.
• Develop and maintain automated tests.
• Build and operate microservices deployed on AWS.
• Create and improve CI/CD pipelines.
• Partner with cyber operations experts to translate domain needs into product features.
• Collaborate with frontend engineers on API contracts and data structures.
• Evaluate new technologies and patterns.

Required qualifications

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

Nice to have

• Delivered software in defense, security, or other mission-critical environments.
• Built systems for analysts, operators, or high-tempo users where speed and reliability matter.
• Integrated AI/ML capabilities into production systems.
• Experience with large-scale data processing and analytics workloads.
• Contributed meaningfully to open-source projects.
• Used observability tooling (metrics, tracing, logging) to debug and improve production systems.

Benefits

• Medical, dental, and vision plan options.
• Life / AD&D, disability coverage options.
• Paid parental leave: 12 weeks for birthing parents, 4 weeks for non-birthing parents, 6 weeks for adoptive, foster, or intended parents.
• Paid holidays and flexible PTO.
• 401(k) with pre-tax and Roth options.
• HSA/FSA options.
• Dependent care FSA.

Before you apply

• Role is limited to U.S. citizens.
• Some positions may require eligibility to obtain and maintain a U.S. Government security clearance.

About the company

Founded in 2024, Twenty Technologies industrializes offensive cyber operations for the U.S. and its allies. Headquartered in Arlington, Virginia, Twenty has raised $168M from various investors.