Senior Software Engineer | API Enterprise | Full-Stack

About the role

You will own the design and delivery of the features that define how global enterprises discover, adopt, and scale DeepL's API platform. You will translate complex enterprise requirements into robust, production-grade solutions that drive measurable adoption and long-term trust. You will act as a product missionary, responsible for understanding the why behind every initiative before defining the how with technical precision. You will partner closely with security, compliance, and operations teams to ensure every capability meets the strictest standards for governance and reliability. You will own the full lifecycle of your services, from initial design through rollout and ongoing optimization in a fast-paced, mission-critical environment. You will contribute to a culture where clarity, accountability, and craftsmanship are non-negotiable. You will help shape the future of how the world communicates by building the infrastructure that makes cross-language collaboration seamless and secure.

Key facts

What you'll do

Design and implement new features for the DeepL API Enterprise platform, focusing on usage insights, cost controls, and consumption governance.

Build and maintain the backend capabilities that power enterprise-grade controls such as roles and permissions, projects, and data residency.

Champion production reliability by participating in on-call rotations and driving observability, monitoring, and SLO enforcement for public API services.

Implement rigorous contract testing and quality gates to prevent breaking changes and ensure secure, predictable behavior for enterprise consumers.

Collaborate with stakeholder teams across the organization to navigate dependencies and deliver cohesive, end-to-end platform capabilities.

Architect and evolve integrations that connect DeepL's API platform with enterprise identity, billing, and security systems.

Optimize the developer and admin experience for enterprise IT and security teams through clear, intuitive tooling and dashboards.

Ensure compliance and auditability by designing controls that meet regulatory requirements and support enterprise risk assessments.

Work within the existing technical and organizational landscape of DeepL's API and enterprise ecosystems to ship reliable, scalable solutions.

Support the transition from a software-first mindset to a product-first mindset by focusing on long-term adoption and user outcomes.

Requirements

You have a Bachelor's or Master's degree in Computer Science, Software Engineering, or a related technical field.

You have 5+ years of professional software development experience with at least 3 years focused on backend systems.

You have deep expertise in C# and .NET, including building scalable backend systems, RESTful API design, and distributed architectures in production environments.

You are experienced working with high-scale distributed systems and understand how to design for reliability, performance, and maintainability.

You have a strong grasp of API design principles, including versioning, security, and idempotency, and you apply them consistently in your work.

You are comfortable owning services end-to-end, including monitoring, observability, logging, and incident response as part of production on-call responsibilities.

You understand enterprise IT and security concerns such as RBAC, data residency, audit trails, and compliance requirements, and you design with these in mind.

You are a strong communicator who can collaborate effectively with cross-functional teams and stakeholders, including enterprise customers when needed.

Nice to have

Experience building and operating platform products in a SaaS environment.

Familiarity with modern observability tools and practices for distributed systems.

Knowledge of authentication, authorization, and identity integration patterns in enterprise contexts.

Experience working with regulated industries and compliance frameworks relevant to data handling.

Practical notes

Location: London

Engagement: Full-time

Candidates must be eligible to work in the United Kingdom without sponsorship.

The role is based in DeepL's London office, and remote work arrangements are not available for this position.

Interviews will be conducted in English.

About DeepL

DeepL is hiring for Senior Software Engineer | API Enterprise | Full-Stack. The listing location is London.

This Senior Software Engineer | API Enterprise | Full-Stack opening is posted for London.