Senior Software Engineer

H Company; Greater London; Hybrid; GBP 70,000 - 90,000; Full time

Job summary

A leading AI startup is seeking a Senior Software Engineer to define and lead technical architecture, develop scalable systems, and mentor engineers. This hybrid role in London requires 5+ years of backend development experience, preferably in Python and Golang, along with expertise in distributed systems and cloud computing (AWS). Join a dynamic team to shape the future of AI and enjoy a competitive salary and opportunities for professional growth.

Benefits

Competitive salary

Professional growth opportunities

Collaborative environment

Qualifications

• 5+ years of experience in backend development, preferably in Python and Golang.
• In-depth experience with distributed systems or cloud computing, preferably in AWS.
• Expertise in building APIs and integrating with external services.

Responsibilities

• Define and lead technical architecture and long-term engineering roadmap.
• Develop and maintain high-performance scalable systems.
• Mentor and guide engineers across teams.

Skills

Backend development

Python

Golang

Distributed systems

Cloud computing (AWS)

API development (REST/GraphQL)

Relational databases

Message queueing (SQS/RabbitMQ/Kafka)

Mentorship

Cross-Functional Communication

Job description

About H

H exists to push the boundaries of superintelligence with agentic AI. By automating complex, multi‑step tasks typically performed by humans, AI agents will help unlock full human potential.

About the Team

The Product Engineering team is responsible for developing H’s Enterprise Platform, providing all the tools and services to support critical operational use‑cases for our customers. Our platform includes key services, from executing computer‑use agents at scale, to orchestrating complex workflows and providing a complete observability, troubleshooting and evals suite of tools. Our Product Engineering team is at the heart of our company’s development, bridging the gap between AI research and real‑world impact, and works closely with all parts of the organization.

Key Responsibilities

• Define and lead technical architecture, design, and long‑term engineering roadmap.
• Develop and maintain complex, high‑performance, and scalable systems.
• Mentor and guide engineers across multiple teams, fostering technical excellence.
• Conduct thorough code and design reviews, ensuring quality and security best practices.
• Collaborate with Research, Product, and other stakeholders to deliver impactful solutions.
• Drive improvements in system reliability, scalability, and observability.
• Establish and enforce engineering standards, tooling, and processes.
• Champion technical innovation and proactively address technical debt.

Requirements

• Technical skills
  • Previous demonstrable role(s) as Senior Software Engineer with relevant set of responsibilities and achievements
  • Strong 5+ years of experience in backend development (Python & Golang preferred)
  • In-depth experience with distributed systems or cloud computing, preferably in AWS
  • Experience building and shipping end to end solutions
  • Experience building APIs (REST and/or GraphQL) and integrating with external services
  • Expertise in relational and non‑relational databases
  • Experience working with message queueing technologies (SQS/RabbitMQ/Kafka/etc.)
  • Solid understanding of coding standards, architectural patterns and test frameworks
  • Expertise in instrumentation, observability and monitoring
• Soft skills
  • Mentorship & Influence - You inspire and elevate engineers across teams - you are a true force multiplier.
  • Cross-Functional Communication - You communicate effectively with engineers and business leaders, switching between technical and business contexts.
  • Technical Leadership – You are able to guide teams through complex technical decisions, balancing short-term delivery with long-term architectural health.

Location

• Paris or London.
• This role is hybrid, and you are expected to be in the office 3 days a week on average.
• Please expect some travel between offices on a reasonable cadence (e.g., every 4-6 weeks).

What We Offer

• Join the exciting journey of shaping the future of AI, and be part of the early days of one of the hottest AI startups.
• Collaborate with a fun, dynamic, and multicultural team, working alongside world‑class AI talent in a highly collaborative environment.
• Enjoy a competitive salary.
• Unlock opportunities for professional growth, continuous learning, and career development.

If you want to change the status quo in AI, join us.