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Monolith

Principal Software Engineer

On site

London, United kingdom

Senior

Full Time

07-12-2025

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Skills

Communication Leadership Python Kubernetes Stakeholder Management Prioritization Decision-making Architecture Systems Architecture Organization Azure AWS Spark

Job Specifications

We're seeking a Principal Software Engineer to lead the architectural evolution of our platform as we scale to meet growing demand from the world's largest engineering companies. This is a hands-on technical leadership role where you'll drive critical architectural initiatives while mentoring our engineering team.

You'll be owning in conjunction with the VP Engineering the technical vision and execution of our platform's evolution to a more distributed architecture, making it AI-agentic ready for the next generation of AI applications.

Key Responsibilities

Technical Leadership & Architecture

Drive the ongoing transition from monolithic to distributed architecture
Design and implement architecture to be AI-agentic ready, enabling rapid deployment of AI products and MCP server integrations
Own technical decisions balancing immediate business needs with long-term architectural goals

Hands-On Development

Write production-quality Python code for critical platform components
Build and optimize distributed compute services
Implement reliable workflow orchestration patterns

Team Mentorship & Collaboration

Mentor mid-level developers, elevating the technical capabilities of the entire team
Establish engineering best practices and architectural patterns
Collaborate with product and business stakeholders to translate requirements into technical solutions
Guide technical decision-making and prioritization across the engineering organization
Interview and onboard new engineers

Technical Requirements

Must-Have

12+ years of software engineering experience with at least 2 years in principal/staff engineering roles
Expert-level Python development skills with production experience at scale
Deep expertise in distributed systems architecture
Strong Kubernetes experience with production workloads
Hands-on experience with workflow orchestration tools (Temporal, Airflow, or similar)
Cloud platform expertise (AWS required, Azure beneficial)
Experience with data processing frameworks (Spark, Athena, or similar)
Proven track record of leading architectural transformations in growing companies
Excellence in technical communication and stakeholder management
Experience with systems having ML Engineering and ML Ops aspects

What We're Looking For

Technical Excellence: You write clean, maintainable code and design systems that scale
Pragmatic Problem-Solver: You balance perfectionism with shipping, making smart trade-offs between short-term delivery and long-term goals
Strong Leadership: You proactively identify problems and drive solutions forward
Mentorship Mindset: You elevate others through knowledge sharing and patient guidance
Ownership Mentality: You take full responsibility for outcomes and drive initiatives to completion
Customer Obsession: You understand that our success is measured by our customers' success

About the Company

Monolith is trusted by the world’s top engineering teams to build self-learning models that empower your engineers to do less testing, more learning, and develop better quality products in half the time. Our end-to-end cloud platform enables any engineer to use their test data and expertise to solve intractable physics problems. It's designed by engineers, for engineers. Quickly design AI pipelines and train models without advanced programming or data science experience. Understand how your design works and which paramete... Know more