Senior Software Engineer - Front End - EXT

Job summary

Are you an accomplished Software Engineer looking for a role where you can make a real impact, using your technical experience to enable us to deliver our Statistics for the Public Good strategy for the UK?

We are looking for an experienced Software Engineer to join us. We are looking for forward-thinking people with a passion for Continuous Integration and Continuous Delivery working on the latest cloud and software applications. You will have an eye for detail and stakeholder management skills to provide technical and procedural expertise working within our Digital Services (DS) Directorate.

This campaign is for external candidates who wish to be based at either our Newport or Tichfield site. Therefore this campaign has been linked with the internal advert 460910 Senior Software Engineer - Front End. If you are an internal candidate to ONS please apply via the other campaign.The selection and interview process will be combined, so you do not need to apply to both campaigns.

Job description

A Software Engineer designs, develops, runs, tests and improve software that meets the user’s needs. They are responsible for writing clean, secure code following a test-driven approach. They create a code that is open by default and easy for others to use. A senior developer delivers and integrates complicated or higher risk software to form a complete service.

The ONS Design System has been developed to help teams deliver digital services that are consistent, accessible, and user centred, while reducing duplication of effort and speeding up delivery. Components developed within the Design System are used for all public-facing ONS sites including Census 2031, Survey Data Collection, and the new Website which is launching in 2026.

Responsibilities

The role will include:

• Maintaining the Design System, triaging and prioritising fixes and improvements in collaboration with the Product and Delivery Manager.
• Collaborating with User Research, Interaction Design, and stakeholders to understand the context for improvements to the Design System.
• Support web accessibility and web page performance.
• Contributing to improvements in related products, and in the team's ways of working.
• Technologies used within the team include: CSS, JavaScript, Nunjucks, Node, GitHub, some full stack development (terraform, config), HTML, WCAG and web standards, Craft CMS.

Person specification

Essential Skills Criteria

You will be working as a Front-end Software Engineer on the team. Key skills include:

• Software Engineer (Practitioner): Collaborates with others when necessary to review specifications. Uses these agreed specifications to design, code, test and document programs or scripts of medium to high complexity, using the right standards and tools. Contributes to code reviews and gives constructive feedback to others.
• Test engineering (Practitioner): Able to design, implement and execute a wide range of functional and non-functional testing techniques and to standardise their application across team. Able to make decisions on running types of test cases, and environments for testing. Able to raise defects with the business and help prioritise them based on defect severity. Develops, extends and maintains reusable test frameworks and tooling; maintains and adapts CI/CD pipelines to ensure effective test integration and quality gates. Guides and coaches others to create and maintain comprehensive standards and compliant automated tests, while researching future tools, methodologies and techniques.
• Service support (Practitioner): Identifies, locates, and competently fixes faults. Able to investigate undocumented issues and develop fixes. Can triage issues and build stories for more involved issues, document processes and support colleagues.
• User focus (Practitioner): Able to collaborate with user researchers and can represent users internally. Understands the difference between user needs and desires of the user. Able to champion user research to focus on all users. Can prioritise and defines approaches to understand the user story, guiding others in doing so. Can offer recommendations on the best tools and methods to be used.

Behaviours

We'll assess you against these behaviours during the selection process:

• Working Together
• Managing a Quality Service
• Delivering at Pace

Technical skills

We'll assess you against these technical skills during the selection process:

• Programming and Build (Practitioner)
• Test Engineering (Practitioner)
• Service Support (Practitioner)
• Communication between technical and non technical (Practitioner)

Benefits

Alongside your salary of £44,050, Office for National Statistics contributes £12,761 towards you being a member of the Civil Service Defined Benefit Pension scheme. Find out what benefits a Civil Service Pension provides.

The Office for National Statistics is part of the Civil Service, and as such we share a number of key benefits with other departments, whilst also having our own unique offerings to support our valued colleagues across the organisation.

Whether you are hearing about us for the first time or already know a bit about our organisation, we hope that our careers site will give you a great insight into the benefits and facilities available to our colleagues, and our fantastic working culture.

Inclusion & Accessibility

At ONS we are always looking to attract the very best people from the widest possible talent pool, and we are proud to be an inclusive, equal opportunities employer. As a Disability Confident Leader we’re committed to ensuring that all candidates are treated fairly throughout the recruitment process.

As part of our application process, you will be prompted to provide details of any reasonable adjustments to our recruitment process that you need. If you would like to discuss any reasonable adjustments before applying, please contact the recruitment team in the first instance.

If you would like an accessible version of any of the attachments or recruitment documents below or linked to in this advert, please contact the recruitment team who will be happy to assist.

Things you need to know

Artificial intelligence

Artificial intelligence can be a useful tool to support your application, however, all examples and statements provided must be truthful, factually accurate and taken directly from your own experience. Where plagiarism has been identified (presenting the ideas and experiences of others, or generated by artificial intelligence, as your own) applications may be withdrawn and internal candidates may be subject to disciplinary action. Please see our candidate guidance (opens in a new window) for more information on appropriate and inappropriate use.

Selection process details

This vacancy is using Success Profiles (opens in a new window), and will assess your Behaviours, Experience and Technical skills.

Security Clearance

For ONS the requirement for SC clearance is to have been present in the UK for 3 consecutive years immediately prior to applying and the department will consider eligibility by exception on a case-by-case basis. You will be asked to provide information regarding your UK residency during your application, and failure to provide this will result in your application being rejected.

If you are unsure that you meet the eligibility above, please read the information available on Gov.uk on this link, or contact the recruitment email on the advert before applying to discuss, as failure to meet the residency requirements will result in your security clearance application being rejected and any offer of employment being withdrawn.

At the point of SC application, you will need to provide or give access to the following evidence:

• Departmental or company records (personnel files, staff reports, sick leave reports and security records)
• UK criminal records covering both spent and unspent criminal records
• Your credit and financial history with a credit reference agency
• Security Services records

For full guidance in relation to the use of AI through the recruitment process, please read A candidate’s guide to artificial intelligence (AI) in recruitment

Please note that all campaigns may be subject to withdrawal at any stage if the internal resource position changes.

Application Process

Number of Stages: 2 stage process

Stage 1: Application

Stage 2: Interview

Stage 1 – Application

The assessment process at the application stage will be based on your work history, skills, experience, CV, and personal statement. It is important that your application is tailored to highlight the skills, knowledge, and experience relevant to the role.

A personal statement is required at application stage, the maximum wordcount allowed is 1250 words, which should not be exceeded. You should provide evidence for each essential skill criterion listed in the person specification. As these criteria are scored, it is advisable to give clear examples for each one, including the impact of your actions, ideally utilising the STAR technique (Situation, Task, Action, Result).

Please note that Success Profiles Behaviour examples are not required at this stage of the application process.

When a high volume of applications are received, the sift pass mark may be adjusted. Candidates will be invited to interview based on their merit order, with those achieving the highest scores being prioritised. Applicants who score below the adjusted pass mark but still pass will be placed on hold and may be invited to interview at a later date.

Stage 2 – Interview

If invited to interview, you will be assessed using techniques aligned with the Civil Service Success Profiles framework, covering all behaviours listed in the job advert and any required technical skills.

A presentation may be required at interview.

Interviews may be in person or via Microsoft Teams.

A reserve list may be held for a period up to 12 months from which further appointments may be made.

The Sift will be conducted from 01/06/2026

Interviews will be conducted from 10/06/2026

For the full terms and conditions of the post, please see attachment.

Near Misses

We often have similar roles available at different grades. If a candidate is suitable for a similar role or a lower grade than they have applied for, we may offer the candidate that role without the need to go through a further selection process providing the role has the same behaviours and essential skills.

GDD Pay

This role is eligible for the Government Digital and Data (GDD) Capability and Pay Framework. If you are successful at interview, your salary will be directly linked to your capability outcome, as determined by your performance in the Technical section of the interview.

• Capability Outcome: Assessed based on scores achieved during the technical interview.
• Salary Determination: Your starting salary will reflect the capability level assigned.
• Feedback: Full feedback on your capability outcome will be provided at the point of offer.

All successful candidates are required to undertake an annual capability assessment as part of their ongoing employment terms. The outcome of this assessment directly influences individual pay levels:

• Higher Capability Outcome: Results in an increase in pay.
• Lower Capability Outcome: Results in a decrease in pay.

Completion of the assessment is mandatory. Failure to complete the annual capability assessment will result in the individual being transitioned to ONS pay terms and conditions, with a corresponding adjustment to their pay.

If you're already in a GDD Group 1 role and receiving GDD pay, and you make a lateral move (i.e. same grade, different role):

• Initial Capability Assessment:
• Development Plan:
• Reassessment at 6 Months:

Starting salary for roles within the Government Digital and Data (GDD) Capability and Pay Framework is determined solely by the capability outcome achieved during the recruitment process.

Please note:

• Existing allowances (scarce skills) will not be taken into account when calculating starting salary.
• This policy applies to all candidates, including existing Civil Servants and ONS colleagues transitioning to the GDD Capability and Pay Framework.

Curious about Government Digital and Data? Dive into the Candidate Pack to learn more

Feedback will only be provided if you attend an interview or assessment.

Security

Successful candidates must undergo a criminal record check.Successful candidates must meet the security requirements before they can be appointed. The level of security needed is security check (opens in a new window).

See our vetting charter (opens in a new window).People working with government assets must complete baseline personnel security standard (opens in new window) checks.

Nationality requirements

This job is broadly open to the following groups:

• UK nationals
• nationals of the Republic of Ireland
• nationals of Commonwealth countries who have the right to work in the UK
• nationals of the EU, Switzerland, Norway, Iceland or Liechtenstein and family members of those nationalities with settled or pre-settled status under the European Union Settlement Scheme (EUSS) (opens in a new window)
• nationals of the EU, Switzerland, Norway, Iceland or Liechtenstein and family members of those nationalities who have made a valid application for settled or pre-settled status under the European Union Settlement Scheme (EUSS)
• individuals with limited leave to remain or indefinite leave to remain who were eligible to apply for EUSS on or before 31 December 2020
• Turkish nationals, and certain family members of Turkish nationals, who have accrued the right to work in the Civil Service

Further information on nationality requirements (opens in a new window)

Working for the Civil Service

The Civil Service Code (opens in a new window) sets out the standards of behaviour expected of civil servants.

We recruit by merit on the basis of fair and open competition, as outlined in the Civil Service Commission's recruitment principles (opens in a new window).The Civil Service embraces diversity and promotes equal opportunities. As such, we run a Disability Confident Scheme (DCS) for candidates with disabilities who meet the minimum selection criteria.The Civil Service also offers a Redeployment Interview Scheme to civil servants who are at risk of redundancy, and who meet the minimum requirements for the advertised vacancy.

Diversity and Inclusion

The Civil Service is committed to attract, retain and invest in talent wherever it is found. To learn more please see theCivil Service People Plan (opens in a new window) and the Civil Service Diversity and Inclusion Strategy (opens in a new window).

Apply and further information

This vacancy is part of the Great Place to Work for Veterans (opens in a new window) initiative.Once this job has closed, the job advert will no longer be available. You may want to save a copy for your records.

Contact point for applicants

Job contact :

• Name : Government Digital and Data Recruitment Team
• Email : Government-Digital-and-Data-Recruitment@ons.gov.uk

Recruitment team

• Email : Government-Digital-and-Data-Recruitment@ons.gov.uk

Further information

If you feel your application has not been treated in accordance with the Recruitment Principles and you wish to make a complaint, in the first instance, you should contact recruitment.complaints@ons.gov.uk. If you are not satisfied with the response you receive from the Department, you can contact the Civil Service Commission here

Attachments

2721 DDAT Advert 1B Permanent - ONS National v1-00 Opens in new window (pdf, 87kB)