Lead App Security Engineer - Threat Modeling & Tooling

Klarna; Greater London; On-site; GBP 48,000 - 70,000; Full time

Job summary

Klarna in London is seeking a Lead Engineer for the Secure Development team to help prevent security flaws before they reach production. You will work hands-on with engineering, perform threat modeling and architecture reviews, and drive security improvements across services.

The role emphasizes building tooling, automation, and robust security processes, with opportunities to influence design decisions and mentor engineers across multiple Klarna platforms and countries.

Qualifications

• Experience solving security issues pragmatically with risk-based decisions.
• Ability to break down complex systems and propose practical fixes.
• Experience with web/mobile/security and cryptography is preferred.
• Strong English communication skills.

Responsibilities

• Perform threat modeling and architecture reviews with engineering teams.
• Drive security improvements through active architectural decisions.
• Build and improve Klarna's security tooling, automation, and processes.
• Conduct security assessments including code reviews and pen tests.
• Contribute to Klarna's internal security community.

Skills

Security engineering

Threat modeling

Code review

Penetration testing

English proficiency

Architectural reviews

Communication with engineers

Tools

Java

JavaScript

Python

Go

Erlang

Scala

NodeJS

Cloud

Job description

Klarna in London is seeking a Lead Engineer for the Secure Development team to help prevent security flaws before they reach production. You will work hands-on with engineering, perform threat modeling and architecture reviews, and drive security improvements across services.

The role emphasizes building tooling, automation, and robust security processes, with opportunities to influence design decisions and mentor engineers across multiple Klarna platforms and countries.