Role Introduction

We are looking for an experienced Senior ServiceNow Developer – NowAssist & TPSM to take agreed requirements and process designs through to working, tested, supportable configuration on the ServiceNow platform. This role makes the technical decisions that determine whether a solution scales, performs, and can still be maintained three releases from now.

You will be the senior technical voice in the Workflow Development team — building the platform's generative AI capability into live service operations, extending TPSM to support how we serve our customers, and setting the build standards the rest of the team works to. You will be expected to challenge requirements where a simpler or more sustainable technical approach exists, and to be clear about where AI genuinely earns its place and where it does not.

What You Will Do

Key Responsibilities:

• Designing and building solutions across the ServiceNow platform, with particular focus on NowAssist capabilities (generative AI skills, AI agents, Virtual Agent, AI Search) and the TPSM product suite.
• Configuring and tuning NowAssist skills — including prompt design, grounding against the right data sources, and evaluating output quality before release.
• Building and extending TPSM capability, including case management, install base and product catalogue, entitlements, order management and Service Bridge integrations where relevant.
• Translating requirements and process designs into technical designs, then into configuration and code, making and documenting the trade-offs along the way.
• Support in the building integrations between ServiceNow and adjacent systems using the appropriate pattern (REST/SOAP, IntegrationHub, Flow Designer, MID Server) and defending the choice of pattern.
• Writing and maintaining automated and manual unit tests, and supporting the Business Analyst through end-to-end and multi-application testing.
• Owning the technical quality of releases — code review, adherence to platform best practice, upgradeability, and keeping customisation to the minimum the requirement genuinely needs.
• Taking changes through platform governance, including CAB submission, technical risk assessment and post-release verification.
• Setting the team's development standards and definition of done, and technically guiding and mentoring other developers.
• Diagnosing and resolving complex platform issues, including those arising from ServiceNow family releases and upgrades.
• Working with the Business Analyst, process leads and SMEs to challenge requirements where a better technical approach exists.

#LI-PB1

What You Will Have

 

• 6-8 years hands-on ServiceNow development experience, including complex, multi-application delivery.
• Deep working knowledge of the platform: data model, ACLs, Flow Designer, Business Rules, Script Includes, Client Scripts, UI Builder or Service Portal, and release management via update sets or source control.
• Strong JavaScript, with the judgement to know when scripting is the right answer and when configuration is.
• Practical experience building with NowAssist — generative AI skills, AI agents or Virtual Agent — in a production or near-production setting, not solely proof of concept.
• Experience with TPSM, CSM or a comparable customer-facing ServiceNow product line, including install base and entitlement models.
• Proven integration experience across REST/SOAP, IntegrationHub and MID Server, including authentication, error handling and volume considerations.
• Experience through full family release upgrade cycles, with an understanding of what makes a build survive them.
• The ability to explain technical decisions and risk clearly to non-technical stakeholders, and to push back constructively when a requirement is unworkable.
• Experience mentoring or technically leading other developers

Desirable: 

• ServiceNow Certified Application Developer plus CIS accreditation in CSM, TPSM/TSM or ITSM.
• Experience with Now Assist Skill Kit. 
• AI Search tuning or the Generative AI Controller. 
• Automated Test Framework and CI/CD tooling 
• A background in a software vendor, MSP or technology provider environment. 

   Success Looks Like:

• TPSM supports the customer-facing service model with minimal customisation, and remains upgrade-safe.
• Builds pass through family release upgrades with little or no remediation.
• Integrations are stable at volume and fail predictably, with errors surfaced rather than swallowed.
• Development standards and a definition of done exist, are followed by the team, and code review is routine rather than exceptional.
• Technical risk reaches leadership early, framed in terms they can act on.
• Other developers in the team are visibly better at their craft than when they joined.

 

What We Do For You

• Wellbeing focused – Our people are our greatest assets, and ensuring everyone feels their best self to come to work is integral. 
• Annual Leave – 20 days of annual leave, plus public holidays 
• Employee Assistance Programme – Free advice, support, and confidential counselling available 24/7.
• Personal Growth - Regardless of where you are at in your career, we’re committed to enabling your growth personally and professionally
  • Development Programmes – From Future Managers to Leadership Training, our development programmes help you get where you need to go
  • Online Learning Platform: SkillsHub! - Learning at your fingertips, anytime from anywhere. You can access our online library with relevant content for your career growth. 
• Life Insurance - 3x annual salary 
• Personal Accident Insurance - providing cover in the event of serious injury/illness.
• Performance Bonus – Our Group-wide bonus scheme enables you to reap the rewards of your success

Who We Are

At OneAdvanced, we are at the forefront of delivering sector-focused technology solutions that simplify complexity, drive meaningful progress, and help build a fairer, more inclusive society.

 

We’re much more than a software company. We deliver SaaS workflow applications and IT services that power organisations across Education, Government, Healthcare, Legal, Manufacturing, Housing, Retail, and more.

OneAdvanced is one of the UK’s largest business software and services companies. Based in Birmingham (The Mailbox), operating across the UK, Ireland, India, and Australia.

Our secure, scalable platform, including OneAdvanced AI, our private AI service for UK organisations, powers connectivity and innovation across critical sectors. Alongside our software are our IT services, including hosting, managed services, and application modernisation.

We strive to create an inclusive workplace that drives innovation and collaboration, championing diverse perspectives and ideas. Our Environmental, Social and Governance (ESG) strategy is embedded in everything we do, guiding us to create meaningful impact for our people, our customers and the planet.

 

Proud to be recognised in the Financial Times’ Best Employers 2026 list for the second-year running, an independent and data led ranking based on employee feedback. Join us and become part of a team that’s powering the world of work and making a real difference.

Join us and become part of a team that’s powering the world of work and making a real difference.

 

Learn more at www.oneadvanced.com