Lead Software Engineer

TPXImpact Holdings PLC; Greater London; Hybrid; GBP 67,000 - 107,000; Full time

Job summary

Manifesto, part of the TPXimpact group, seeks a senior Umbraco Platform Lead to steer advanced Umbraco environments. You will drive architectural standards, plan upgrades, and manage client expectations across complex digital ecosystems.

You will collaborate with principal engineers, shape delivery plans, and mentor engineers while staying current with Umbraco roadmaps and AI-assisted engineering trends. This UK-wide role offers a competitive salary and impact-driven work.

Qualifications

• Deep Umbraco expertise across recent versions with content modelling and package ecosystem.
• Strong .NET and C# capability with modern practice.
• Experience planning and delivering major Umbraco version upgrades on live platforms.
• Experience maintaining platforms over years and debt management.
• Experience designing APIs and integrations within complex ecosystems (CRM, payments, marketing).
• Security-focused development with data protection in mind.
• Experience leading agile delivery and mentoring engineers.

Responsibilities

• Provide senior technical leadership on the Umbraco platforms we manage.
• Set standards for building, extending and maintaining client platforms.
• Plan and lead major Umbraco upgrades and assess compatibility.
• Maintain technical health and surface risk early.
• Decide hosting and deployment strategies on Umbraco Cloud or equivalents.
• Lead the delivery of high quality software on time and budget.

Skills

Umbraco expert

C# .NET

API design

Agile leadership

Security best practices

WCAG accessibility

Azure cloud

CI/CD pipelines

CRM integrations

Headless Umbraco

Tools

Azure

React

WordPress

Job description

Salary: £67,000 - 107,000 per year

Requirements:

• Deep, demonstrable Umbraco expertise across recent major versions, including content modelling, custom development and the package ecosystem.
• Strong .NET and C# capability, with a solid grasp of modern .NET practice.
• Proven experience planning and delivering major Umbraco version upgrades on live platforms.
• Experience maintaining and evolving established platforms over years, with an understanding of technical debt management.
• Experience designing and implementing APIs and integrations within complex digital ecosystems, including CRM, payment and marketing platforms.
• Strong expertise in database design and efficient querying in a web application context.
• Practical experience with cloud platforms and managed hosting, particularly Azure and Umbraco Cloud, plus CI/CD pipelines and environment management.
• Experience building responsive, accessible interfaces with a component-based approach.
• Deep commitment to building to WCAG standards.
• Proven ability to apply security best practice throughout the development lifecycle, particularly around personal and payment data.
• Proven leadership in agile delivery, with a focus on quality outcomes and collaborative teams.
• Exceptional problem-solving ability and confidence managing technical client relationships directly.
• Desirable: Azure services, headless or decoupled Umbraco, modern front-end frameworks such as React or Next.js, donation or payment platforms, Drupal or Wordpress, AI-assisted engineering practice, or experience in the charity, non-profit or membership sector.

Responsibilities:

• Provide senior technical leadership on the Umbraco platforms we are responsible for.
• Set and uphold standards for how we build, extend and maintain client platforms.
• Make architectural decisions appropriate to the clients budget, team and long-term maintenance capability.
• Plan and lead major Umbraco version upgrades, assessing package and integration compatibility and managing risk.
• Maintain a clear view of the technical health of the platforms we support and surface risk early.
• Make sensible decisions about hosting, environments and deployment on Umbraco Cloud and equivalent platforms.
• Contribute to shared Umbraco standards and practice across the business.
• Consult with principal engineers and contribute to high-level architecture during the Foundations phase of a project.
• Provide broad plans for technical delivery, including themes, risk, size and delivery order.
• Produce estimates that clearly state what is in scope, out of scope and any assumptions.
• Manage client expectations about agile delivery and sprint outcomes.
• Lead the delivery of high quality software on time and to budget.
• Ensure project team members are engaged throughout development.
• Ensure agile ceremonies happen at the right time with the right people present.
• Ensure the team delivers committed work by the agreed deadline.
• Uphold quality through code review and maintain standards under delivery pressure.
• Apply particular rigour to donation journeys, payment integrations and supporter data.
• Ensure the team collaborates well and escalates issues appropriately.
• Act as the senior technical point of contact for clients.
• Lead the technical response when issues occur and direct the fix.
• Ensure clients are supported by the appropriate team members.
• Ensure the smooth operation of support boards and unblock technical team members.
• Provide technical continuity for long-term retainer clients.
• Develop engineers through pairing, review and structured mentorship.
• Stay current on tools, standards and trends, including the Umbraco roadmap and AI-assisted engineering practice.
• Contribute ideas for the growth of the engineering team.
• Collaborate with principal engineers and engineering leadership to deliver departmental goals.
• Produce relevant content on software engineering and agile delivery to raise the profile of the department.

Technologies:

• AI
• Azure
• C#
• CI/CD
• Cloud
• CRM
• Drupal
• Support
• Marketing
• React
• Security
• Umbraco
• Web
• WordPress
• ASP.NET
• API
• CMS
• DevOps
• GraphQL
• LESS
• REST

More:

We are Manifesto, the digital experience agency for changemakers, and part of the TPXimpact group, a Certified B Corporation. We create award-winning digital experiences, products and services that are ethical, inclusive, accessible, sustainable and joyful for clients including UNICEF UK, Breast Cancer Now, Trussell, Woodgreen, The Royal Academy of Arts, Zoological Society London, Historic Environment Scotland and Fauna & Flora. We are a team of 130 digital product leaders, creative designers, user experience designers, engagement specialists, software engineers and experience strategists. This is a UK-wide role with a salary of 55,000 to 62,000 per annum. We are committed to having a positive impact on the clients and communities we serve and actively encourage applications from all genders, ethnicities, disabled people, members of the LGBTQIA+ community and those from lower socio-economic backgrounds. If you do not meet 100% of the criteria, we still want to hear from you, and we welcome requests for adjustments during the recruitment process.