215,132+ Codebase Engineer Jobs in UK — Top Companies Hiring June 2026

Professional job seekers finding United Kingdom jobs through Expertini
750,000+ professionals on Expertini 750,000+ Candidates
Join our global community
Expertini Penguin Mascot Resume Score™
Resume Score™ Instantly
Upload Your CV
Quick 30-second process

Apply Today & Jumpstart Your Career on Expertini, Trusted Since 2008.

Reset

Create Job Alert

 
   
Reset

Principal Engineer Codebase, Platform & DevOps Assessor

Intelance is an independent enterprise architecture, technology and cybersecurity advisory firm. We have been appointed to lead a board-level, independent technology and data review for a large UK omnichannel retailer.A big part of this retailer's technology is home-built. We need a hands-on princi ...

Principal Engineer Codebase, Platform & DevOps Assessor

Intelance is an independent enterprise architecture, technology and cybersecurity advisory firm. We have been appointed to lead a board-level, independent technology and data review for a large UK omnichannel retailer.A big part of this retailer's technology is home-built. We need a hands-on princi ...

Head of Support Engineering — Own Live Debug & Scale

Connecting Education is seeking a Senior Support Engineer to lead the support function and work closely with the Engineering team. You will directly diagnose and fix issues in the codebase, while also managing the existing Support Engineer. The role is pivotal, requiring ownership, strong technical ski ...

Embedded Software Engineer

OverviewExpleo are seeking an experienced Embedded Software Engineer to support the delivery of a software engineering work package for ongoing vehicle intercom development. The role focuses on developing low-level peripheral drivers and system software for an embedded platform based on the NXP i.MX8 (A5 ...

Senior C++ Engineer for High Performance Spectral Platform

Wiley is seeking a Senior Software Engineer (P3) to drive the modernization of the KnowItAll platform. The role involves working with a large, mature C++ codebase, focusing on performance and scientific correctness. Candidates should have strong professional C++ experience and be comfortable improving ...

Senior Cloud Test Engineer – Private Cloud Automation

Stars Arena is seeking a Senior Software Test Engineer for their Apple Private Cloud project in London, UK. This full-time position demands in-depth experience in software automation and development, along with strong programming skills in Python, Swift, and Bash. Candidates should have familiarity with Git and ...

Defence Software Engineer—AI, Cloud, Hybrid Role

Faculty is seeking an ambitious Software Engineer to join our Defence team in the UK. You will work on cloud and edge computing, collaborating closely with technical leaders and integrating solutions in a hybrid working environment. The ideal candidate will have experience with Python and other languag ...

Owner First Full Stack Engineer for AI Tools

Aperture is seeking a serious engineer to own the Aperture OS codebase. This role demands end-to-end feature development, API integrations, and a strong understanding of performance marketing tools. We're a remote-first team focused on impact, allowing you to work flexibly while ensuring high-quality o ...

Platform Engineer: Terraform, CI/CD & Equity

Golang Works is seeking a Platform Engineer in London, UK. This full-time role involves working within a Python and Go codebase, developing infrastructure-as-code with Terraform, and managing CI/CD pipelines. As part of an ambitious startup, you will have the chance to engage directly with the founders and contr ...

Senior C++ Engineer for High Performance Windows Apps

Wiley is seeking a Senior Software Engineer in the UK to enhance the KnowItAll platform. You will work on performance-sensitive algorithms and improve a C++ codebase fundamental to scientific analysis, collaborating closely with domain experts. This role requires strong C++ skills and a commitment to g ...

Senior Software Engineer: Python & C/C++ Refactor Lead

Data Careers is seeking a MOD DV Cleared Senior Software Engineer for a permanent position located in Fareham. This role involves hands-on maintenance, enhancement, and evolution of complex software systems with a competitive salary ranging from £80,000 to £90,000 plus benefits. The successful candidat ...

Senior Frontend Architect for AI Driven SaaS

A leading AI-driven SaaS company is seeking a Mid-Senior Front-End Engineer to architect scalable web applications. You will define patterns for a React + TypeScript codebase, enhance developer experiences, and mentor teams. The ideal candidate has 8+ years in large-scale web applications and a passion for perfo ...

Senior AI Native Software Engineer: Orchestrate AI Delivery

Benivo is seeking a Senior Software Engineer (AI-Native Development) to enhance software development speed and quality through effective AI orchestration. The ideal candidate will combine deep engineering judgment with the ability to leverage AI tools throughout the software lifecycle, maintaining strict qual ...

Senior Full Stack Engineer: Architect & Ship Web Features

Legora, based in Greater London, is seeking a Software Engineer to help build and ship products that empower legal professionals globally. You will take ownership of your codebase, ensuring high-quality, secure, and timely development. The ideal candidate has several years of experience in full stack d ...

Frontend Engineer II (React/TypeScript) Scale Checkout

BigCommerce Pty is seeking a Software Engineer II - Frontend to work in London, UK. This role focuses on building high-quality features using React and TypeScript while enhancing the performance and maintainability of the codebase. Ideal candidates will have at least 3 years of relevant experience and ...

Remote First Junior Full Stack Engineer (TypeScript/React)

Story Terrace Inc. is seeking a junior Full Stack Software Engineer to improve internal LegalTech systems. You'll work with a TypeScript codebase and collaborate with legal and operational staff to develop features and debug issues. Ideal candidates have a Bachelor's in a Scientific or Technology field ...

Embedded Software Engineer (Bare Metal / Device Driver Development)

Overview Expleo are seeking an experienced Embedded Software Engineer to support the delivery of a software engineering work package for ongoing vehicle intercom development. The role focuses on developing low-level peripheral drivers and system software for an embedded platform based on the NXP ...

Senior Search Platform Engineer — Elasticsearch & Python

9fin is seeking a Senior IC Engineer to manage their Elasticsearch cluster and collaborate on the search infrastructure. You will play a pivotal role in improving the codebase and mentoring junior engineers, ensuring delivery of efficient solutions. Your expertise in Elasticsearch, Python, and APIs wil ...

Remote First Full Stack Engineer (TypeScript/React)

Story Terrace Inc. is looking for a Full Stack Software Engineer to maintain and improve their internal LegalTech systems. The candidate will work on a production TypeScript codebase, contributing to both frontend and backend development, integrating third-party APIs, and participating in code reviews. <p ...

Senior iOS Engineer — Scale Apps, Learn & Grow

ASOS.com is looking for a Senior iOS Engineer to enhance our Customer Experience team and contribute to the success of our iPhone and iPad apps. The role involves delivering high-quality experiences using modern iOS technologies at scale for over 8 million global users. Key responsibilities include col ...

Kotlin Multiplatform Mobile Engineer – Equity & Impact

A leading reusable packaging provider in London seeks a Mobile Software Engineer to own the migration to Kotlin Multiplatform and impact waste reduction directly. The role involves developing a unified codebase for iOS and Android, collaborating on backend services, and maintaining client applications. The ideal ...

Senior Test Engineer in London LinuxRecruit

Senior Test Engineer London, United Kingdom Tech stack GitLab JUnit CI/CD Java SOLID Qualifications Solid understanding of all things automation; strong preference for coding with Java as the primary codebas ...

Platform Solutions Engineer — Hybrid + Equity

Story Terrace Inc. is seeking its first Solutions Engineer to engage customers throughout the entire lifecycle, from sales to post-sales support. You'll provide technical demos, manage onboarding for enterprise clients, and contribute to the Kratix codebase, helping steer product development. The ideal ...

Principal Software Engineer: Cloud Modernisation Lead

AVEVA Denmark is seeking a Principal Software Engineer to lead the modernisation of sophisticated process optimisation platforms. This role combines architectural leadership with hands-on software development, transforming a legacy C++ codebase and shaping the future of industrial software. The ideal c ...

Mid Level Web Engineer React/TypeScript, Hybrid Role

Trainline is looking for a Mid Level Web Engineer to enhance our platform with innovative features. You will work with React, Typescript, and various modern tools to maintain a high-quality codebase and ensure customer satisfaction. This position offers fantastic benefits such as private healthcare, generous wor ...

Senior .NET Engineer: Build scalable web apps

A software development company in the UK is seeking a Senior Software Engineer to join its Product Engineering teams. The ideal candidate has extensive experience in collaborative software development, specifically with Microsoft .NET and C#. Responsibilities include delivering high-quality software, managing te ...

Lead Mobile Engineer: Kotlin Multiplatform & Equity

Jack & Jill is seeking a Mobile Software Engineer to lead the migration of mobile applications to a unified Kotlin Multiplatform codebase. You'll work closely with the Head of Tech in a dynamic climate tech startup that focuses on reducing environmental waste. The ideal candidate has 1-2 years of exper ...

VP Full Stack Engineer (Kotlin/Python) – Hybrid & Growth

Citigroup Inc. is seeking a Full Stack Engineer (Kotlin and/or Python) at the VP level to design and develop innovative solutions within Equities Technology. In this role, you'll enhance trader workflow tooling and engage with business users globally. You will have the autonomy to influence technology decisions ...

Frontend Engineer in London MoonPay

Frontend Engineer London, United Kingdom Responsibilities Write fully tested, high‑quality, and performant code on an existing codebase. What You’ll Be Working With Typescript React and Next.js Node.js TypeORM, TypeDI, TypeGr ...

Algorithms Software Engineer

Join to apply for the Algorithms Software Engineer role at Morson Talent This range is provided by Morson Talent. Your actual pay will be based on your skills and experience — talk with your recruiter to learn more. Base pay range Direct message the job poster from ...

Mobile Software Engineer (£40k–£45k + Equity) at Cauli

Job Title Mobile Software Engineer Salary £40,000–£45,000 + Equity Company Description Cauli is the UK's largest reusable packaging provider, led by Forbes 30 Under 30 CEO Josephine Liang. They utilize IoT and AI-driven technology to replace single-use waste at ...

Lead Engineer (Contract)

This is initially a rolling contract engagement. For the right person, there is a potential path to a permanent role with equity. About the company We're an early-stage B2B fintech building verification and credit management infrastructure for the UK and European markets. Our platform rep ...

Senior Support Engineer Own the support function at a fast growing EdTech with serious techni[...]

Are you a strong Support Engineer who wants more than a ticket queue? Ready to own a support function, get hands‑on in the codebase every day, and help scale a product that’s genuinely making schools better? This might be the role for you. The company Our client is a fast‑growing EdTech c ...

Senior Software Test Engineer Apple Private Cloud in London Apple Inc.

Senior Software Test Engineer - Apple Private Cloud London, United Kingdom Tech stack Objective-C Bash Swift Python Git Cloud C Minimum Qualifications In-depth experience in software automati ...

Software Engineer

Software Engineer – Desktop applications and real-time systemsA global high-tech engineering company in the semiconductor sector is seeking a Software Engineer to support the modernisation and evolution of the software that powers their platforms used worldwide.If you enjoy working with complex, ...

Senior Software Engineer

**Brighton, United Kingdom****Senior Software Engineer**LocationBrighton, United KingdomDepartmentEngineeringRequisition IDJOBREQ-2615823**Role description** **The opportunity** Parsec creates ultra-low latency, high-performance remote desktop technology that emp ...

Product Design Engineer AI

Product Design Engineer - AI (Contract | UK Remote) You design it. You build it. You ship it. If that's how you work, read on. We're hiring for one of the world's most recognisable tech brands - a contract role until December 2026, 100% remote within the UK, paid we ...

Product Design Engineer AI

Product Design Engineer - AI (Contract | UK Remote) You design it. You build it. You ship it. If that's how you work, read on. We're hiring for one of the world's most recognisable tech brands - a contract role until December 2026, 100% remote within the UK, paid we ...

Product Design Engineer AI

Product Design Engineer - AI (Contract | UK Remote) You design it. You build it. You ship it. If that's how you work, read on. We're hiring for one of the world's most recognisable tech brands - a contract role until December 2026, 100% remote within the UK, paid we ...

Product Design Engineer AI

Product Design Engineer - AI (Contract | UK Remote) You design it. You build it. You ship it. If that's how you work, read on. We're hiring for one of the world's most recognisable tech brands - a contract role until December 2026, 100% remote within the UK, paid we ...

C++ Production Support Engineer

Job Title: C++ Production Support Engineer Location: Hybrid London, UK (3Days/Week) Duration: 6months+ 500GBP/Day Inside IR35 Role Overview We are looking for a hands-on C++ Production Support Engineer to support and enhance a legacy ...

C++ Production Support Engineer in London

Job Title: C++ Production Support Engineer Location: Hybrid London, UK (3Days/Week) Duration: 6months+ 500GBP/Day Inside IR35 Role Overview We are looking for a hands‑on C++ Production Support Engineer to support and enhance a legacy ...

Senior Software Engineer

This role is a perm position. Clearance: DV Location: Portsmouth - 3 days a week onsite. Requirements Senior hands‑on engineer for complex maintenance and upgrade work across the primary languages and interop patterns used (e.g., Python with C/C++ bindings; MATLAB/Si ...

Senior Frontend Software Engineer (Vue3) PoS Team in London Boost inc

Boost Inc. Job Opportunity Boost Inc. is on a mission to redefine unattended retail. As we continue to scale our global UI platform, migrating legacy front-ends to a modern, consolidated Vue 3 codebase with Composition API, we’re seeking a Senior Frontend Software Engineer to accelerate... R ...

Software Engineer (Ruby on Rails)

Addooco is a managed IT, cloud, and communications solutions provider specializing in enterprise-grade services for businesses of all sizes. Established in 2008, the company operates across the United Kingdom region and beyond, focusing on proactive management and in-house developed solutions delivered thr ...

Founding Product Engineer

Overview Engineering workforce planning is broken. There's never really been a solution. Spreadsheets passed between people who don't speak the same lingo. Engineering says one thing, finance hears another, the powers that be get a number that's already wrong. And now whole companies are burning ...

Senior / Mid Level .NET Engineer (Game Integrations)

Senior / Mid-Level .NET Engineer (Game Integrations) Location: North West England (Hybrid/Remote Options) Salary: £45,000 - £55,000 (Dependent on experience) Reporting to: Software Engineering Manager About the Role We are an iGaming company who specialise in the ...

Mobile/ Frontend Engineer

Location London, UK - Hybrid – 3 days in office - Office location: Central London (Victoria area) About the Role We are looking for a Front-End Engineer with strong React Native and TypeScript experience to help build and improve a tablet-based Point of Sale (POS ...

MOD DV Cleared Senior Software Engineer

MOD DV Cleared Senior Software Engineer. Permanent position located Portsmouth / Home (on site 3 days a week). Salary: £80,000 – £90,000 (benefits). This is a hands‑on senior engineering role focused on maintaining, improving and evolving complex software systems. Key Responsibilities ...

🚀 Boost Your Hiring Chances with Our AI-Powered Tool-Kit

Stand out from thousands of applicants. Use our proven career tools to optimize your applications and land your dream job faster.

To-Do Planner

Organize your job search and personal tasks. All data is confidential.

Open Planner

Wellbeing Center

Access your confidential wellness report and resources to manage job search stress.

Check Wellbeing

Skill Coach

Plan your skill development with O*NET support to stay competitive in your field.

Start Coaching

Outfit Helper

Get AI-powered suggestions on what to wear for your next interview.

Find Outfit

Income Tax Calculator

Plan your finances with our calculator, updated for 2025 tax regulations.

Calculate Tax

Salary Benchmark

Get accurate, AI-supported salary trends to know your worth and negotiate better.

Check Salaries

Interview Practice

Practice for any interview with AI-enabled Q&A sessions. All data is private.

Start Practicing

Interview Predictor

Use our AI-supported tool to predict potential interview questions based on your resume.

Predict Questions

Interview Practice Timer

Use our mock interview trainer to perfect your answers under timed conditions.

Start Timer

Behavioral Mastery

Ace tricky behavioral interviews with our AI-powered practice module.

Master Answers

Question Journal

Confidentially record interview questions you were asked for future reference.

Open Journal

Interview Ace

A comprehensive tool to help you master every aspect of your interviews.

Become an Ace

Q&A Logs

Confidentially track your answers to common questions and refine them over time.

View Logs

Application Planner

Schedule and organize your job applications in one confidential planner.

Open Planner

Cover Letter Tool

Create perfect, tailored cover letters for each application with AI support.

Generate Letter

Resume Score

Get instant feedback on your resume with our NLP-supported analysis tool.

Check My Score

ATS Score

Check your resume's compatibility with Applicant Tracking Systems (ATS).

Check ATS Score

Application Analyzer

Use AI to analyze job descriptions and optimize your application materials.

Analyze Application

Career Visualizer

Confidentially plan and visualize your long-term career path and goals.

Visualize My Career

Offer Genius

Get intelligent insights and strategies to confidently negotiate job offers.

Negotiate Offers

JobFlow

Track your entire job search progress from application to offer with this intelligent tool.

Track My Flow

JobSense

Our intelligent matching engine that provides smart job recommendations.

Get Smart Matches

Networking Toolkit

Tools to build and manage your professional connections. All data is confidential.

Build Network

Professional CV

A classic, O*NET supported template for corporate and professional roles.

Use This Template

Executive CV

A premium, O*NET supported template designed for senior and C-level positions.

Use This Template

Modern CV

A fresh, stylish, O*NET supported template perfect for tech and modern industries.

Use This Template

Creative CV

A visually distinct, O*NET supported template for design and artistic roles.

Use This Template

Minimalist CV

A clean, simple, O*NET supported template that focuses purely on content.

Use This Template

Europass CV

The standard European Union recommended format for wide compatibility.

Use This Template

Student CV

An institution-recommended template perfect for internships and first jobs.

Use This Template

Graduate CV

An institution-recommended template for recent graduates entering the workforce.

Use This Template

Academic CV

The researcher-recommended format for roles in academia and research.

Use This Template

Developer/IT CV

A tech-savvy recommended template to highlight your technical skills.

Use This Template

Skilled Worker CV

A trades-recommended template to showcase hands-on skills and experience.

Use This Template

Monochrome CV

A sleek, black-and-white, O*NET supported template for a professional look.

Use This Template

Art CV

An artist-recommended template that allows your creativity to shine.

Use This Template

Harvard CV

A researcher-recommended template based on the classic Harvard format.

Use This Template

Volunteer Research

Help us improve our platform by joining our community research program.

Join Research

Review Us

Share your experience with our tools to help other job seekers.

Share Experience

Register

Create your free account to save jobs, build your profile, and track applications.

Create Account

Login

Access your dashboard, manage applications, and continue your job search.

Access Your Account

Profile Builder

Create a comprehensive professional profile that attracts recruiters and showcases your skills.

Build Your Profile

View Profile

See your public profile exactly as employers will see it. Make sure it's perfect.

Preview Profile

Bookmarked Jobs

Keep track of all your saved job opportunities in one organized place.

View Saved Jobs

Your Reviews

View and manage all the company reviews you've submitted.

See Your Reviews

Following

Manage the list of companies you follow to stay updated on their new openings.

Manage Following

Find Companies

Discover and research top employers in your country and industry.

Discover Employers

Standalone CV Builder

Use our O*NET supported CV builder to create a professional resume from scratch.

Build Your CV

PDF to DOC (Beta)

Convert your PDF resumes or documents into editable Word (DOC) format.

Convert PDF

DOC to PDF (Beta)

Create universally compatible PDF documents from your Word (DOC) files.

Create PDF

General FAQ

Find answers to common questions about our job site and platform.

Read FAQ

Job Seekers FAQ

Get help and find answers to questions specifically for job seekers.

Get Help

Job Matching

Learn about the technology and algorithms behind how we match you to jobs.

Learn How

Personalized Matching

Discover how we use your profile and activity to provide customized job suggestions.

Learn More

Quick Apply

Understand our fast application process and how to make the most of it.

Learn More

Alert Frequency

Learn how to manage your job alert settings so you get the updates you want.

Manage Settings

Job Alerts Guide

A complete guide to understanding how job alerts work and how to use them effectively.

Read Guide

Resume Matching

Learn how our system matches your resume to job requirements.

Learn More

Ethical Branding

Read our guide to building a professional and ethical personal brand.

Read Guide

Candidate Visibility

Learn how to increase your visibility to recruiters on our platform.

Increase Visibility

Verified Badge

Find out how you can get a verified badge to build trust with employers.

Get Verified

AI ATS Technology

Learn about the advanced AI and ATS technology that powers our platform.

Learn More

ATS Ranking

Understand how Applicant Tracking Systems rank you as an applicant.

Learn More

Semantic Matching

Learn how our AI-powered semantic matching goes beyond keywords.

Learn More

    Codebase Engineer Jobs in United Kingdom Job Search Guide, Trends and Insights