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# Principal Software Engineer

- **Company:** Hargreaves Lansdown
- **Location:** Bristol, UK
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** Java (Programming Language), PHP (Programming Language), Amazon Web Services, Architectural Patterns, Cloud Engineering, Software Design Patterns, Industry Standard Architecture, Node.Js, TypeScript, Data Logging, Enterprise Software Applications, ReactJS, Event Driven Architecture, Kubernetes, Amazon Simple Queue Service (SQS), Terraform, Docker
- **Published:** October 16, 2026
- **Apply:** https://hargreaveslansdown.wd3.myworkdayjobs.com/HargreavesLansdown/job/Welcome-Building/Principal-Software-Engineer_R9712

## About the Role

Essential:

 * Demonstrated leadership in legacy technology transformation.

 * Strong expertise in modern architectural patterns, cloud-native design, and container orchestration.

 * Skilled communicator able to influence and engage at every level of the organisation.

 * Proven ability to balance trade-offs, costs, and technical constraints.

 * Experience coaching teams towards engineering and architecture best practices.

 * Deep understanding of design patterns, security, networking, observability, and system flows.

 * Adept at producing clear, concise architectural documentation.

Tech stack:

 * TypeScript / React / Node.js / Terraform

 * AWS: Kubernetes / ECS / Docker / Lambda / SQS / DocumentDB

Desirable:

 * Previous experience as a Solution or Enterprise Architect.

 * Background in enterprise systems and legacy-to-modern transitions.

 * Familiarity with PHP and/or Java

 * Understanding of Developer Experience optimisation tools and frameworks., Full-time, with hybrid working, a minimum of 2 days in our Bristol office.

## Description

As a Principal Software Engineer in our Investment Growth Tribe, you'll be a senior technical leader, playing a key role in our technology transformation.

This is a strategic role, where you'll shape and communicate high-level architectures, set clear and supportive guardrails, work on POCs with teams, support them during challenging times, and empower engineering teams to deliver high-quality, data-driven solutions. It's about influence, clarity, and enabling teams to thrive - with a focus on being approachable, engaged, and collaborative.

What You'll Be Doing

 * Define and document high-level solution architectures, clearly outlining trade-offs, risks, and dependencies.

 * Provide clear architectural principles and best-practice guidelines that empower teams to design excellent solutions.

 * Foster a culture of data-driven decision-making, defining cross-team metrics that support continuous improvement.

 * Promote strong documentation practices, including Architectural Decision Records, Solution Memos, and C4 diagrams.

 * Guide cloud architecture choices, particularly around container orchestration and the use of AWS services.

 * Champion best practices for observability, logging, security, and networking.

 * Identify opportunities to enhance Developer Experience and efficiency through smarter tooling and frameworks.

 * Support engineering teams with mentoring, pairing, and skills development.

 * Lead conversations around Event-Driven Architecture, cost forecasting, and designing for the future state.

 * Partner with Product and Engineering Managers to align priorities and delivery approaches.