Senior Security Engineer — Go, AWS, Product Security

numi; Greater London; On-site; GBP 120,000 - 160,000; Full time

Job summary

numi Partners is seeking a senior engineer with deep security expertise to join a small engineering team building mission-critical infrastructure for government and law enforcement clients. You will ship production Go services and React front-ends on AWS, ensuring what is shipped withstands adversarial scrutiny.

You will embed security throughout design, development, and operations, setting the standard for secure engineering and driving threat modelling, secure SDLC practices, and incident

Qualifications

• Five+ years as a software engineer with security-focused work.
• Strong backend development; Go preferred, other languages acceptable.
• Hands-on ownership of cloud security in production AWS environments.
• Experience with application security in web apps and relational DBs.
• Familiarity with threat modelling as a regular discipline.

Responsibilities

• Design, write, review, and ship production Go and React code.
• Lead threat modelling on new features and architecture changes.
• Own AWS security posture: IAM, network segmentation, secrets management, data isolation.
• Incorporate security into the SDLC: dependencies, vulnerabilities, CI/CD controls, static/dynamic analysis.
• Develop security features: audit trails, access controls, tamper evidence, data isolation.
• Lead incident response activities: detection, investigation, remediation, drills.

Skills

Go

React

Security engineering

Threat modelling

AWS

PostgreSQL

CI/CD security

Code review

Tools

Go

React

PostgreSQL

AWS

Job description

numi Partners is seeking a senior engineer with deep security expertise to join a small engineering team building mission-critical infrastructure for government and law enforcement clients. You will ship production Go services and React front-ends on AWS, ensuring what is shipped withstands adversarial scrutiny.

You will embed security throughout design, development, and operations, setting the standard for secure engineering and driving threat modelling, secure SDLC practices, and incident