193 jobs found

Senior Backend Engineer (PHP) - OOP, PHP, MySQL, TDD - Fareham, Hampshire. This is an in office role. - Salary circa £60,000 plus benefits An exciting new opportunity for a Senior Backend Engineer to join an entrepreneurial business based in Fareham. Working within a dedicated LAMP environment and reporting to the project manager, you will be helping to plan and develop the product and its internal driven websites, data migration and help with support and maintenance of security and storage services. This innovative technology company have several brands specialising in a variety of high tech solutions including security, data backup and cloud storage platforms. You will be using latest release PHP and web technology including XHTML, CSS, jQuery and Agile/Scum methodology. The work is aimed at more back end development with an emphasis on Agile processes, systems optimisation, TDD and embracing modern development practices. The company also uses PHPUnit / Selenium to ensure high standards of development. Desired skill set that includes: OOP PHP5+ MySQL Git Beneficial Skills: Kubernetes Google Cloud / AWS Docker Load Balancing TDD Code Review The company offer an unrivalled volume of new projects, Greenfield development and the opportunity to work with and learn from some of the sharpest developers in the area. On top of a competitive salary the company offer some fantastic financial and lifestyle benefits including; free access to local gym and health spa, onsite chef (free cooked breakfast & lunch!), childcare vouchers, cycle to work scheme, pension, BUPA healthcare. To be considered for this position please send your CV to or call Spectrum IT Recruitment (South) Limited is acting as an Employment Agency in relation to this vacancy. JBRP1_UKTJ

Job Title: Senior Backend Developer Location: Liverpool City Centre on a hybrid working basis Salary: £65,000 - £75,000 depending on experience We're looking for a passionate Senior Backend Developer who thrives on solving complex problems and building systems that scale. You'll be at the forefront of creating next-generation backend services that genuinely make a difference for our customers and business. In this role, you'll have the freedom to lead, the support to grow, and the chance to mentor others - because we believe learning and sharing knowledge is what makes a team truly exceptional. We believe great work happens when talented people have the best tools. That's why you'll have top-of-the-range equipment and a workspace designed for creativity, collaboration, and getting things done. What You'll Do: Build and maintain scalable microservices in .NET 8.0 and Azure. Write clean, testable code with a focus on performance and maintainability. Collaborate with product owners and designers to shape features from concept to delivery. Participate in code reviews and mentor junior developers. Architect robust APIs and database solutions with clean, maintainable code. Deploy and manage applications using Docker and Azure cloud services. Contribute ideas, share feedback, and grow together with a team that values openness and collaboration. Bonus: Clean Architecture Understanding Clean Architecture and Mediator Pattern is a huge plus! If you have it, you'll help us build maintainable, testable systems that follow industry best practices. Our Tech Stack: Backend: C#, .NET 8.0, ASP.NET Core Database: SQL Server, Entity Framework Infrastructure: Docker, Azure Tools: Unit and Integration Testing, Git, Agile methodologies What We're Looking For: Proven senior-level experience building microservices running on Docker. Expertise in C#, .NET 8.0, and ASP.NET Core. Strong experience with SQL Server and Entity Framework. Hands-on experience with Unit and Integration Testing. A natural collaborator with strong communication skills - you thrive in a team setting. A culture fit who loves mentoring others, sharing ideas, and helping the whole team level up. Self-motivated, with a problem-solving mindset and a passion for building robust, scalable systems. Understanding Clean Architecture and Mediator Pattern is desirable but not mandatory. Bonus Points For: Understanding Clean Architecture, Mediator Pattern Solid grasp of asynchronous communication in distributed systems Experience with high-throughput, data-intensive systems Contributed towards systems utilising Event-Driven Architecture Why Join Us? Modern tech stack and a strong culture of engineering excellence Hybrid options within the UK Career progression into tech leadership or architecture Supportive environment with clear standards and plenty of opportunity to innovate Why Acorn Insurance? Acorn Insurance want to give you more than a job, we want to give you a purpose and a career. So, what can we offer you as an employer? Some of the "your tomorrow" benefits you will receive include: Wellbeing: Enhanced Annual Leave entitlement starting at 31 days and potentially increasing to 35 days per year depending on grade & length of service (including bank holidays) Enhanced paternity pay and 16 weeks full maternity pay. Colleague Assistance programme offers a suite of wellbeing services such as: 6 Free Counselling sessions per year Unlimited access to a telephone councillor 24/7 Access to a free 4-week programme of cognitive behavioural therapy (CBT) with a trained therapist mentor. Network of internal qualified mental health first aiders are available to provide support to colleagues. Financial: A core level of life assurance with the option to increase cover via salary sacrifice and add your spouse/partner Ability to access your earnings before payday via Dayforce Wallet. Refer a friend scheme with a £250 bonus for every colleague recommended on passing their probation period. Access to a flexible benefits platform including an annual flex pot allowance to spend on over 15 benefits of your choice. Ability to give back. You can opt into donating money to charity to climate positive organisations directly from your salary. Reward, Recognition and Culture: Long Service Award paid on 5,10- and 15-years' service A reward and recognition hub to celebrate and reward colleagues and peers. Consistent and engaging company events including company awards, competitions and charity fundraisers. Budgets for department leaders to use for social and engagement events. All roles are subject to DBS and Financial checks, any offer made will be conditional until checks are completed to a satisfactory standard. Candidates with experience or relevant job titles of; Software Developer, Senior System Developer, Software Engineer, Systems Developer, Software Tester, Backend Services, API's, API, Application Programming Interface may also be considered for this role.

Senior Python Backend Developer Central London - one day a week in the office £75-85k + benefits We're seeking a topflight Senior Python Backend Developer with a strong software engineering background including 7+ years majoring in writing Backend applications using Python and Django (Rest Framework). This is a seriously weighty, complex, technically challenging role; the successful Python Backend Developer will be 'red hot' on the core backend skill requirements. Demonstrably the 'go to' person in your role. DevOps expertise is strongly advantageous. The backend Python Developer will be joining a team of 45 at a world-class healthcare scaleup. With each integration of a new hospital group there is an acceleration of the rapid scaling of patient user numbers - you will help to solve these challenging scaling problems. Responsibilities: Work on new product features contributing to architecture and implementation Refactor existing code and services to support scalability and growth of complexity Proactively respond to analytics to ensure products are robust and meet users' needs Take technical ownership of areas of product Required: 7+ years of experience writing backend applications using Python and Django (Rest Framework) or related frameworks, e.g. Flask, FastAPI Good understanding of ORM (either Django or SQLAlchemy) Good understanding of Python Unit Testing frameworks and TDD practices Experience working with Cloud Infrastructure (Ideally AWS) Strong background in DevOps Good understanding of Git, and CI/CD Nice-to-haves: Deeper understanding of SQL Knowledge of front-end technologies such as Vue or React Experience with handling sensitive data (e.g. PII) Experience working in a startup environment Senior Python Developer Senior Backend Python Developer Senior Software Engineer

Chroma is currently working with a leading high-street retailer that's expanding their development team and looking to hire a Senior Full Stack Engineer. This role offers a salary of up to £80,000 , alongside 10% Annual Bonus , and a hybrid working model (2-3 days per week in their Central Manchester office).Their business is shifting from traditional operations to a digitally driven model, modernising its platforms and introducing innovative solutions to enhance customer experience. This is an exciting time to join as they invest heavily in scalable architecture, event-driven systems, and AI-driven capabilities. The Role We're looking for a forward-thinking Full Stack Software Engineer with experience in enterprise-scale environments and a passion for building exceptional digital experiences. This role offers the chance to work on mission-critical backend APIs (70%) and dynamic front-end applications (30%), leveraging modern frameworks and event-driven architecture. You'll also have the opportunity to lead and mentor a team (minimum 2 years' leadership experience required), fostering a culture of collaboration and continuous learning. Your work will directly shape the digital platforms that underpin the company's future growth. Key Responsibilities Deliver high-quality, performant backend microservices and APIs alongside engaging front-end experiences. Lead technical decision-making and coach team members to drive best practices. Translate business requirements into technical solutions, ensuring scalability and security. Troubleshoot and resolve complex issues across front-end and back-end systems. Advocate for engineering excellence, including CI/CD, TDD, and infrastructure as code. Stay ahead of emerging technologies and contribute to innovation initiatives. Skills & Experience Must Have: Proven experience in enterprise-scale organisations and consumer-facing businesses. Strong proficiency in current TypeScript, Node.js, React, Next.js. Expertise in event-driven architecture and building well-tested, reliable systems in the cloud. Minimum 2 years' experience managing or leading a team. Knowledge of CI/CD pipelines, observability, and infrastructure automation. Excellent communication skills and ability to engage stakeholders. Familiarity with Google Cloud Platform (GCP), Azure or AWS Desirable: Experience in Retail, QSR, or eCommerce industries. Background in driving extreme programming practices (TDD, pair programming, continuous delivery). If this role sounds of interest, please apply here or give Megan a call on .

Senior Full Stack Developer, London (Hybrid) Avanti Recruitment is working with an award-winning digital consultancy. They are seeking a Senior Full Stack Developer to join their growing team. This is an opportunity to work on high-impact digital projects for purpose-driven organisations and contribute to the evolution of a modern, innovative development function. You will collaborate closely with strategists, designers, and developers to build exceptional web applications, take full ownership of development projects, and help shape technical direction across the studio. This role is ideal for someone who thrives in a creative environment, enjoys solving complex problems, and values craftsmanship in engineering. Tech stack: Vue.js, Nuxt, Headless CMS, Laravel or Node.js Key Responsibilities • Lead end-to-end development of bespoke, responsive websites and digital experiences • Build modern front-end interfaces with Vue.js, Nuxt and contemporary tooling • Develop and integrate backend services and APIs within headless CMS architectures • Work with CSS pre-processors to create scalable, maintainable styling systems • Implement best practices in performance, accessibility, security, and SEO • Deploy and manage applications and server environments (Laravel Forge, AWS) • Develop and maintain GraphQL schemas, endpoints, and queries • Support and mentor other developers, contributing to a collaborative culture • Stay current with modern development trends and introduce new ideas to improve workflow and product quality Skills and Experience Required • Professional experience in full-stack or backend-focused roles • Advanced knowledge of Vue.js, Nuxt.js, JavaScript, TypeScript and SCSS • Strong backend development skills in Node.js, PHP / Laravel or equivalent • Solid experience working with headless CMS platforms and API-first ecosystems • Understanding of AWS services such as S3 • Experience with A / B testing tools, GraphQL and API development • Excellent communication skills and confidence working with non-technical stakeholders • Portfolio demonstrating high-quality development work (preferred) • Experience in a digital or creative agency environment (preferred) Why Apply You will be joining a supportive, ambitious, purpose-driven team working on projects that make a real impact. You will have the autonomy to shape technical decisions while collaborating with an inspiring multidisciplinary studio.

GenAI Full Stack Engineer - Consultant / Senior Consultant Salary: 45,000 - 70,000 pa + 4,000 Bonus plus benefits, perks and healthcare options Job Type: Permanent - Hybrid / 2 x days per week - Travel to client site Base Locations: London, Manchester, Newcastle, Glasgow Overview: We're looking for a GenAI Full Stack Engineer who is passionate about solving real-world challenges through technology. You'll work closely with senior stakeholders both internally and within key clients to create GenAI strategies that translate business issues into relevant technical solutions and competitive propositions that are scalable, secure, and sustainable. Your Role: Collaborate with the team to develop GenAI proof-of-concepts (POCs) for clients using technologies like Retrieval-Augmented Generation (RAG) and intelligent agents. Scale existing POCs to production-ready solutions for customer use. Design and develop Full Stack applications for both GenAI and non-GenAI projects. Support the development of infrastructure to enable robust end-to-end solutions. Grow your skills by exploring and experimenting with emerging technologies, including GenAI. Your skills and experience: Backend Development: Experience in building microservices using either Python with FastAPI, or TypeScript with Express or equivalent Frontend Development: Experience in building React applications using TypeScript, leveraging frameworks such as Next.js or Vite. GenAI Frameworks: Familiarity with tools like LangChain, LangGraph, CrewAI, or Vercel AI (in Python or JavaScript). LLM experience: Practical experience with Large Language Models (LLMs) such as OpenAI, Anthropic, Mistral, or Llama, and tools like Ollama. Cloud Platforms: Proficiency in AWS or Azure for hosting and deployment. Containerization and Orchestration: Hands-on experience with Docker, Kubernetes, and Docker Compose. Infrastructure as Code (IaC): Exposure to tools like Terraform. Monitoring Tools: Familiarity with LLM monitoring tools like Langsmith, Langfuse, or similar. CI/CD: Experience with continuous integration and deployment tools such as GitLab, GitHub, or Jenkins. Vector Databases: Experience with and (but not limited to) ChromaDB, Pinecone, PGVector, MongoDB , Qdrant etc. NoSQL: Familiarity with NoSQL databases (e.g., MongoDB preferred). SQL: Experience working with SQL databases like PostgreSQL. Proficient in Git and version control platforms like GitHub, GitLab, etc. To be successfully appointed to this role, it is a requirement to obtain Security Check (SC) clearance. If you're ready to take the next step in your career and thrive in a fast-paced, innovative environment, we want to hear from you! Please send updated CV to

Senior Android Engineer (Native Integration & Security) We are seeking an exceptional Senior Android Engineer to join a newly-founded joint venture backed by five of the world's leading telecommunications companies. Our mission is to restore trust in voice communication by building a network-native intelligence layer to combat the global epidemic of voice fraud and AI-driven scams. In this role, you will be the owner of our most critical, user-facing feature: the Telco-Verified Security Shield. You will be responsible for the magic moment of our product, delivering an instant, network-verified trust indicator to a user's device in the moments before they answer the call. This is not a standard mobile app role; it is a deep, Real Time systems challenge that requires you to architect and implement a high-performance, secure, and reliable solution that integrates directly with the Android operating system's native call-handling services. Your primary objective is to own the client-side implementation of our sub-500ms Time-to-Trust (TtT) metric. You will be the driving force behind the trust in our product, working at the intersection of native mobile engineering, Real Time data processing, and client-side security. This position offers a unique opportunity to build a category-defining security product from the ground up, leveraging proprietary, network-level data that no pure-OTT competitor can access. Key ResponsibilitiesNative OS Integration & Performance Architect, build, and own the entire native call interception flow using Android's CallScreeningService to intercept and analyze calls as they ring. Design and engineer the high-performance Trust Indicator overlay, obsessing over every millisecond of client-side processing to ensure we meet our strict sub-500ms Time-to-Trust (TtT) metric. Implement the client-side logic to consume and display Explainable AI reasoning (eg, Recent SIM Swap Detected, Verified Business) provided by our Back End services. Build a robust, efficient, and scalable client-side API integration layer to consume Real Time security signals (like our proprietary Scam_Score) from the AI Core. Security & Quality Implement and champion our mandatory Zero Trust security architecture at the client level, ensuring all network data and user PII are handled with the highest level of security. Define and enforce best practices for performance, code quality, and testing for the entire Android security stack. Work closely with the QA Engineer to build test harnesses and instrumentation to rigorously validate the sub-500ms latency target and ensure a false-positive rate of less than 1%. Cross-functional Collaboration Partner with the Senior Backend Engineer (Application & AI Orchestration) to define the API contracts and Real Time data flow needed to power the Security Shield. Collaborate with the UX/UI Designer to iterate on a seamless, intuitive, and trustworthy user experience for the trust indicator and its explanations. As a foundational engineering hire, you will help define our Android engineering culture, mentor future hires, and set the standard for technical excellence. Required QualificationsEducation & Experience Bachelor's degree in Computer Science, Engineering, or a related field. 5+ years of hands-on experience in native Android development, with a portfolio of high-performance, public-facing applications. Required Technical & Android Skills Expert-level, production-grade experience with native Android development (Kotlin required). Demonstrated, deep expertise with Android's native call-handling APIs, specifically the CallScreeningService framework. This is a critical, non-negotiable skill for this role. Proven experience building high-performance, Real Time user interfaces that are deeply integrated with the Android OS. Strong understanding of mobile security principles and best practices, including secure data storage, network communication (mTLS), and threat modelling. Proficiency in consuming RESTful APIs and Real Time data streams (eg, WebSockets) in a mobile environment. Strong understanding of Android performance profiling tools and techniques to debug and optimize for latency. Experience with multi-threaded and asynchronous programming on Android. Preferred Qualification Advanced Education & Industry Experience Master's degree in Computer Science or a related field. Previous experience in the telecommunications, cybersecurity, or anti-fraud/anti-spam industries. Experience building applications for a global audience with localization and compliance requirements. Experience with the Android NDK (C++) for performance-critical operations. Familiarity with Real Time audio processing on Android. Deep knowledge of mobile network protocols and security. Experience building or integrating SDKs. Advanced Systems & Security Expertise This is a permanent position with hybrid working of two days a week in the central London office and the rest WFH. The salary is very much Dependent on experience with a guide between £110k-£140K basic + package.

Senior Backend Engineer (Application & AI Orchestration) Overview We are seeking a deeply technical and security-minded Senior Backend Engineer to join a newly-founded, high-impact AI joint venture. Backed by five of the world's leading telecommunications giants, our mission is to restore trust in global voice communication. Our mission is to restore trust in voice communication by building a network-native intelligence layer to stop fraud and create a new category of secure, AI-powered user experiences. We are a Phase 2 company, meaning we are building the foundational engineering team that will define our culture and our success. This role is the Core Logic Owner for our flagship AI experience: the Personal Welcome Manager. While our Security Shield product leverages unique, pre-call telco data to provide sub-500ms trust indicators, the Welcome Manager is our AI innovation showcase and primary monetization driver. This product features an AI agent that screens unknown callers as they ring, provides a live transcript, and allows for mid-call user intervention. As the Senior Backend Engineer for Application & AI Orchestration, your central challenge will be solving the cumulative latency puzzle. You will be singularly responsible for orchestrating a best-in-class, buy, don't build AI stack (STT - LLM - TTS) to deliver a seamless, natural, and responsive voice-to-voice (V2V) experience, targeting a sub-1000ms latency from the moment a caller stops speaking to the moment our AI begins its response. You won't just be integrating APIs; you will be architecting the Real Time, high-throughput nervous system of our core AI product. Key ResponsibilitiesAI Orchestration & Core Logic Own the end-to-end Back End architecture for the Personal Welcome Manager, our flagship conversational AI product. Design, build, and optimize the core AI orchestration pipeline (STT - LLM - TTS) to meet our 1000ms V2V latency target. Serve as the technical lead for our "Buy, Don't Build" AI strategy, integrating, managing, and evaluating third-party AI services from providers like Vapi, Deepgram, and Cartesia. Implement the core application logic for all Welcome Manager features, including intent-capture, post-call summarization with entity extraction, and error handling. API & Application Development Design, build, and scale the mission-critical, high-availability RESTful APIs that serve our mobile clients (Android-first). Architect and manage the Real Time streaming data flows (audio and text) required for the live transcription feature, utilizing technologies like WebSocket. Implement the Back End logic for user-facing features, such as mid-call intervention (allowing a user to accept a call during pre-screening). System Architecture & Quality Collaborate on the design of our cloud-native, microservices-based architecture to ensure all application services are scalable, resilient, and cost-efficient. Work with the Platform & Security engineer to ensure all services adhere to our mandatory Zero Trust security architecture and protect sensitive user data. Implement comprehensive monitoring, logging, and alerting for the entire AI pipeline, with a focus on our key latency (V2V), quality, and cost metrics. Cross-functional Collaboration Partner closely with the Senior Android Engineers to define robust API contracts and ensure a seamless, low-latency experience for the live transcript and mid-call intervention features. Collaborate with the Senior Backend Engineer (Telco Integration) to consume and orchestrate the proprietary network signals that power our Security Shield. Work with the Product Manager and UX/UI Designer to translate complex product requirements and the 1000ms UX flow into a concrete technical reality. Collaborate with the DevOps Engineer on CI/CD pipelines, Kubernetes-based service deployment, and infrastructure scaling. Required QualificationsEducation & Experience Bachelor's degree in Computer Science or a related technical field, or equivalent practical experience. 7+ years of hands-on experience in Back End development, building and maintaining high-availability, high-throughput systems in production. Technical & Backend Skills Expert-level proficiency and at least 5 years of production experience with Go (Golang) . This role is centered on Go, and we require deep experience with its concurrency patterns and performance tuning. Strong, proven experience designing, building, and scaling high-availability RESTful APIs for mobile or web clients. Deep experience with distributed systems, microservices architecture, and event-driven patterns. Demonstrated experience with Real Time applications and data streaming technologies (eg, WebSockets, gRPC, Kafka). Experience integrating third-party AI/ML APIs (eg, LLMs, STT/TTS, or other complex services) into production systems. Experience with containerization (Docker, Kubernetes) and deploying/managing services on a major cloud platform (AWS, GCP, or Azure). This is a permanent position with hybrid working of two days a week in the central London office and the rest WFH. The salary is very much Dependent on experience with a guide between £110k-£140K basic + package.

Senior Android Engineer (UI/UX & Welcome Manager) Overview We are seeking an exceptional Senior Android Engineer to join a newly-founded joint venture backed by five of the world's leading telecommunications companies. Our mission is to restore trust in voice communication by building a network-native intelligence layer to combat the global epidemic of voice fraud and AI-driven scams. This is a rare opportunity to be a foundational hire, shaping the future of a product designed to protect hundreds of millions of users. We are building two core products: the Telco-Verified Security Shield (our primary, pre-call fraud detection) and the Personal Welcome Manager (our premium, AI-powered call screening experience). As the Senior Android Engineer for the Welcome Manager, you are the User-Facing Owner of our AI innovation showcase. This isn't just another UI/UX role; you will be the primary architect of a novel conversational interface. Your challenge is to build the magic: the live transcription, the mid-call intervention, the post-call summaries, that defines our premium user experience. You will own the app that we will showcase to the world at Mobile World Congress (MWC) 2026, and your work will be the primary driver for our monetization strategy. Key Responsibilities Conversational UI Architecture: Own the end-to-end development of the Personal Welcome Manager's conversational interface on Android. You will build a fluid, intuitive, and polished user experience from the ground up. Designer-in-Lockstep Collaboration: Work hand-in-glove with our dedicated UX/UI designer, engaging in rapid daily iteration to translate high-fidelity, interactive prototypes into pixel-perfect, production-ready code. Real Time Data Streaming: Engineer the high-performance live transcript view, which displays the AI-screened conversation as the phone is ringing. This involves consuming Real Time streaming text data from our Back End AI orchestration layer via WebSockets. Mastering Perceived Performance: Implement the critical mid-call intervention feature, allowing a user to seamlessly accept a call from the AI agent. You will become an expert in designing for our < 1000ms V2V (voice-to-voice) latency budget, ensuring the entire UX flow feels fast and responsive. API & Backend Integration: Partner with our Back End (Application & AI Orchestration) engineers to define and integrate the client-side APIs and data models required to power the Welcome Manager's features, from live transcription to post-call entity-extracted summaries. MWC Demo Ownership: Be directly responsible for the polish, stability, and performance of the Welcome Manager application for its critical debut at MWC 2026. Cross-Functional Partnership: Collaborate closely with the other Senior Android Engineer (who owns the native CallScreeningService and Security Shield overlay) to ensure a seamless and unified user experience between our two core products within a single application. Required Qualifications? Education & Experience ? Bachelor's degree in Computer Science or a related field, or equivalent practical experience. ? 5+ years of hands-on experience in native Android development, with a strong portfolio of shipped, consumer-facing applications. ? Required Technical & UI/UX Skills ? Deep expertise in native Android UI/UX development, including Kotlin and modern frameworks (eg, Jetpack Compose, Coroutines, Flow). ? Demonstrated experience building complex, Real Time, data-intensive user interfaces (eg, chat applications, financial dashboards, Real Time streaming apps). ? Strong experience integrating with Back End APIs and services, particularly consuming Real Time data via WebSockets, gRPC, or similar protocols. ? Proficiency in translating high-fidelity designs (eg, Figma, Sketch) into beautiful, performant, and maintainable code. ? A strong understanding of Android UI performance optimization, memory management, and threading models. ? Experience with the full mobile development life cycle, from ideation and prototyping to testing, release, and maintenance. Preferred Qualifications ? Advanced UI/UX & Conversational AI ? Prior experience designing or building conversational interfaces (eg, chatbots, voice assistants). ? A strong portfolio that explicitly showcases beautiful, complex, and highly responsive mobile UIs you have built. ? Relevant Technical Experience ? Familiarity with Android's native call-handling APIs (eg, CallScreeningService, ConnectionService), as you will be integrating closely with the engineer who owns this. ? Experience with performance testing and profiling Android applications to hunt down and eliminate bottlenecks. ? Knowledge of mobile application security best practices. ? Industry & Environment ? Previous experience working in a fast-paced, agile startup environment. ? Experience in the telecommunications or voice AI space. This is a permanent position with hybrid working of two days a week in the central London office and the rest WFH. The salary is very much Dependent on experience

Senior Backend Engineer We are seeking a deeply technical and security-minded Senior Backend Engineer to join a newly-founded, high-impact AI joint venture. Backed by five of the world's leading telecommunications giants, our mission is to restore trust in global voice communication. This is not a standard Back End role. We are seeking a foundational engineer to own our single greatest strategic asset: our unique, privileged access to network-level intelligence via the GSMA CAMARA API standard. This is our right to win, and you will be the engineer responsible for building the bridge to it. You will be the Critical Path Owner for Track Zero, the 30-day foundational sprint to validate and integrate the first-ever CAMARA-based signals (like sim-swap and device-roaming-status) from our telco founders. Your success is the Go/No-Go gate for our MWC 2026 launch. You will be directly responsible for building the out-of-band data path that enables our flagship Telco-Verified Security Shield and its sub-500ms Time-to-Trust metric, our core differentiator that no over-the-top competitor can replicate. This position offers a unique opportunity to define a new category of network-aware security, working directly with the world's leading carriers to turn their network data into a Real Time defense against global fraud. Key Responsibilities Telco Integration & Architecture Own and build the Security Signal Ingestion path, the secure, low-latency, and out-of-band data channel connecting to our founding members' network API gateways. Architect and implement a carrier-agnostic, vendor-agnostic connector layer to consume RESTful APIs from a heterogeneous global landscape of telco partners and IMS vendors (eg, Nokia, Ericsson, Mavenir). Serve as the primary technical liaison to the engineering teams at our telco founders (Deutsche Telekom, Singtel, SKT, etc.), working hand-in-glove to navigate, validate, and productionize their new CAMARA network APIs. Design and build the high-throughput microservices that will query, ingest, normalize, and cache network signals (eg, sim-swap, device-roaming-status) to be used in our Real Time Scam_Score model. Implement a mandatory Zero Trust security model for this critical integration, our most sensitive asset. This includes mTLS, least-privilege IAM, and network micro-segmentation. System Ownership & Performance Serve as the Critical Path Owner for Track Zero, our 30-day sprint to validate and integrate Real Time signals from at least two telco partners, culminating in a Go/No-Go demo. Ensure all network API integrations meet the stringent P99 latency budgets (eg, < 150ms) required to support our sub-500ms Time-to-Trust product goal. Collaborate with the platform team to build a parallel development path using mocked data to mitigate risks of network API delays. Define and own the data contracts and pipelines that feed this "ground-truth" network data from the integration layer to our core AI Service Bus (Apache Kafka). Cross-functional Collaboration Work closely with the Scam Detection Service and AI/ML teams to define the feature vectors and data payloads needed from the network to power our proprietary machine learning models. Partner with product and leadership to define the Phase 2 (post-MWC) roadmap for co-developing new, proprietary network APIs (like Caller_Velocity from CDRs) that will become our long-term, indefensible moat. Document integration architectures, data schemas, and security controls to create setup guides for our Founding Member partners. Collaborate with our external InfoSec vendor to ensure the integration layer is continuously validated and hardened against threats. Required Qualifications Education & Experience Bachelor's degree in Computer Science, Engineering, or a related field. 7+ years of hands-on experience in Back End engineering, with a proven track record of building and maintaining high-performance, distributed systems in production. Required Technical Skills A minimum of 5 years of production experience with C++ or Go (Golang). Strong, demonstrable experiefnce with Real Time, low-latency data processing. You obsess over milliseconds and understand the trade-offs. Proficiency with cloud platforms (AWS, GCP, or Azure) and containerization technologies (Kubernetes, Docker). Deep understanding of API design (REST, gRPC, Webhooks) and API security (OAuth 2.0, mTLS, JWTs). Knowledge of (or deep, demonstrable curiosity about) telecommunications protocols and architectures. You must be comfortable talking to network engineers. Experience with high-throughput messaging or streaming platforms (eg, Kafka, Pulsar). This is a permanent position with hybrid working of two days a week in the central London office and the rest WFH. The salary is very much Dependent on experience with a guide between £130k-£160K basic + package.

Senior Backend Engineer (Golang) Overview We are seeking a deeply technical and security-minded Senior Backend Engineer to join a newly-founded, high-impact AI joint venture. Backed by five of the world's leading telecommunications giants, our mission is to restore trust in global voice communication. Our mission is to restore trust in voice communication by building a network-native intelligence layer to stop fraud and create a new category of secure, AI-powered user experiences. We are a Phase 2 company, meaning we are building the foundational engineering team that will define our culture and our success. This role is the Core Logic Owner for our flagship AI experience: the Personal Welcome Manager. While our Security Shield product leverages unique, pre-call telco data to provide sub-500ms trust indicators, the Welcome Manager is our AI innovation showcase and primary monetization driver. This product features an AI agent that screens unknown callers as they ring, provides a live transcript, and allows for mid-call user intervention. As the Senior Backend Engineer for Application & AI Orchestration, your central challenge will be solving the cumulative latency puzzle. You will be singularly responsible for orchestrating a best-in-class, buy, don't build AI stack (STT LLM TTS) to deliver a seamless, natural, and responsive voice-to-voice (V2V) experience, targeting a sub-1000ms latency from the moment a caller stops speaking to the moment our AI begins its response. You won't just be integrating APIs; you will be architecting the Real Time, high-throughput nervous system of our core AI product. Key Responsibilities AI Orchestration & Core Logic Own the end-to-end Back End architecture for the Personal Welcome Manager, our flagship conversational AI product. Design, build, and optimize the core AI orchestration pipeline (STT - LLM - TTS) to meet our 1000ms V2V latency target. Serve as the technical lead for our "Buy, Don't Build" AI strategy, integrating, managing, and evaluating third-party AI services from providers like Vapi, Deepgram, and Cartesia. Implement the core application logic for all Welcome Manager features, including intent-capture, post-call summarization with entity extraction, and error handling. API & Application Development Design, build, and scale the mission-critical, high-availability RESTful APIs that serve our mobile clients (Android-first). Architect and manage the Real Time streaming data flows (audio and text) required for the live transcription feature, utilizing technologies like WebSocket. Implement the Back End logic for user-facing features, such as mid-call intervention (allowing a user to accept a call during pre-screening). System Architecture & Quality Collaborate on the design of our cloud-native, microservices-based architecture to ensure all application services are scalable, resilient, and cost-efficient. Work with the Platform & Security engineer to ensure all services adhere to our mandatory Zero Trust security architecture and protect sensitive user data. Implement comprehensive monitoring, logging, and alerting for the entire AI pipeline, with a focus on our key latency (V2V), quality, and cost metrics. Cross-functional Collaboration Partner closely with the Senior Android Engineers to define robust API contracts and ensure a seamless, low-latency experience for the live transcript and mid-call intervention features. Collaborate with the Senior Backend Engineer (Telco Integration) to consume and orchestrate the proprietary network signals that power our Security Shield. Work with the Product Manager and UX/UI Designer to translate complex product requirements and the 1000ms UX flow into a concrete technical reality. Collaborate with the DevOps Engineer on CI/CD pipelines, Kubernetes-based service deployment, and infrastructure scaling. Required Qualifications Education & Experience Bachelor's degree in Computer Science or a related technical field, or equivalent practical experience. 7+ years of hands-on experience in Back End development, building and maintaining high-availability, high-throughput systems in production. Technical & Backend Skills Expert-level proficiency and at least 5 years of production experience with C++ OR Go (Golang) . Strong, proven experience designing, building, and scaling high-availability RESTful APIs for mobile or web clients. Deep experience with distributed systems, microservices architecture, and event-driven patterns. Demonstrated experience with Real Time applications and data streaming technologies (eg, WebSockets, gRPC, Kafka). Experience integrating third-party AI/ML APIs (eg, LLMs, STT/TTS, or other complex services) into production systems. Experience with containerization (Docker, Kubernetes) and deploying/managing services on a major cloud platform (AWS, GCP, or Azure). This is a permanent position with hybrid working of two days a week in the central London office and the rest WFH. The salary is very much dependent on experience with a guide between £130k-£160K basic + package. Seniority Level Director Industry Telecommunications Information Services Technology, Information and Media Employment Type Full-time Job Functions Information Technology Skills REST

Job Title: Software Engineer / Senior Software Engineers - Linux, C++, Networking, Python (All Levels) Location: Bristol - Hybrid Type: Full-time, 12 month FTC Salary: Competitive, commensurate with experience Whether you have 18 months or 5+ years of relevant experience, if you're passionate about building high-performance systems in a dynamic environment, we'd love to hear from you. About the Role We are partnering with a well-established high-tech scale-up to find experienced Software Engineers to join their dynamic and innovative team. This is a hands-on engineering role where you'll be instrumental in the design, development, and maintenance of advanced systems and associated platforms. You'll work across planned software feature development, real-time troubleshooting, and complex systems integration. This is a great opportunity to deepen your skills in high-performance software and modern infrastructure while working in a collaborative, fast-paced environment. Key Responsibilities Develop, enhance, and maintain robust software solutions for mission-critical systems. Design and implement multithreaded C++ applications for data processing. Script tools and automation in Python to improve system workflows. Integrate software with diverse hardware and networked systems. Troubleshoot and resolve issues in real-time production environments. Collaborate across multidisciplinary teams to deliver high-quality, scalable solutions. Essential Experience 2+ years working with Linux and command-line interfaces. Strong C++ programming experience, including multithreading for data processing. Solid understanding of networking, including Ethernet protocols. Python proficiency for scripting and developing applications/tools. Experience with DevOps pipelines for building and deploying software. Familiarity with Kubernetes and containerised backend services. Desirable Knowledge of Docker for container management. What We Offer A chance to work with cutting-edge technologies on challenging, impactful projects. Opportunities for rapid professional growth and career progression. Flexible working arrangements to support work-life balance. A collaborative, inclusive culture within a fast-growing, high-tech scale-up. Please apply via the link for immediate consideration!

Development Team Lead (PHP8, API's, MySQL)UK Remote Working£65000 - £75000 + Equity Please note my client cannot offer VISA sponsorship for this position. Your new company I am working to recruit an experienced PHP Development Team Lead for a hyper-growth business in the UK as they look to expand globally. It's a really unique opportunity working for an online, technology first organisation that are looking to challenge the leading names in Ecommerce. This role will be split 80% hands-on and 20% leadership/mentoring.The role is offered fully remote but you must be within the UK and must not require any form of Visa Sponsorship to apply. Your new role The Development team has mirrored the general pattern in the company; grow quickly, iterate, have fun, make an impact. As they've scaled over the last year Development squads have been formed so you'll join a team of 4-5 to ensure everyone is focussed and to provide a progression path for all.This company operates like a start-up but with a product that's been in Development for 10+ years. You will understand there is some legacy/maintenance as part of the role building on a custom monolith - but plenty of new work in Laravel to sink your teeth into.Under the guidance of a new Head of Development the team have invested heavily in software best practice and development processes so it's an exciting environment to be joining as they move into new territories globally and launch a mobile app.To fit in here you'll collaborate openly with other Devs, enjoy problem solving and will buy into the vision of the company to disrupt and become number 1 in their field. What you'll need to succeed A hands-on technical leader responsible for developing and maintaining high-quality PHP8 code, managing backend services and APIs, and optimising system performance. 10 years of programming experience as a minimum, experience with Laravel is a bonus. This role will be split 80% hands-on and 20% leadership/mentoring. Oversees a team of developers, providing mentorship, setting priorities, and ensuring timely project delivery through Agile practices. Collaborates closely with Product Managers and stakeholders to align development with business goals, while championing coding standards, CI/CD practices, and continuous improvement. Acts as a key liaison across departments, fostering a collaborative and high-performing engineering culture.Experience building RESTful API's and working with MySQL is essential, and desirable skills include GCP Cloud, RabbitMQ, NoSQL and TDD/Microservices exposure.If you've worked on large scale Ecommerce applications with multiple service calls and databases that would be standout, as would experience working in Agile squads. What you'll get in return The company offers good flexibility both in terms of working hours and remote working (within the UK). There's no micromanagement here and joining at this stage in their journey you'll have a chance to share in the profits (Sharesave scheme) plus there's annual pay reviews. You'll get 26 days holiday + bank holidays and funding for technical courses/training. The company have bi-annual socials to meet and celebrate success. What you need to do now To find out more and to be considered for this position please apply directly, or contact Max Wilcock, Senior Business Director on .At Hays Technology, we are shaping the future of recruitment. The rapid adoption of cloud, which is making customer interfaces more engaging and creating a seamless engagement with businesses, means that from the foundation of your organisation up, software developers are critical to success. As the competition for talent grows, we're ready and waiting to help developers really make an impact on organisations, so talk to us today. We are Hays Technology. Hays Specialist Recruitment Limited acts as an employment agency for permanent recruitment and employment business for the supply of temporary workers. By applying for this job you accept the T&C's, Privacy Policy and Disclaimers which can be found at hays.co.uk

Senior Backend Engineer High-Growth Cybersecurity Scale-Up Fully Remote (Global) Are you ready to build the core systems that power one of the fastest-growing cybersecurity platforms on the planet? This is your chance to join a research-driven, venture-backed security scale-up that's trusted by some of the world's biggest enterprises and critical infrastructure providers. Recognised by Gartner, armed with $29M+ in funding, and scaling aggressively worldwide, they're on a mission to reshape how organisations stay ahead of real-world cyber threats. As a Senior Backend Engineer , you'll play a key role in building scalable, high-performance backend systems that ingest, process, and serve data on millions of assets-helping global security teams uncover exposures before attackers do. What you'll be doing: Designing and building backend services and data pipelines powering a cutting-edge cybersecurity platform Architecting scalable microservices and APIs to process massive volumes of security data Working closely with product and frontend teams to integrate backend services into the platform experience Continuously improving systems performance, deployment, and monitoring as the company scales globally What they're looking for: 5+ years' experience designing and maintaining mission-critical backend applications Strong Python engineering skills , with a track record of building performant, maintainable, and testable systems Solid background in microservices architecture Proficiency with Postgres & MongoDB (relational + non-relational) Experience with event-driven architectures and asynchronous workflows (Kafka, Airflow, etc.) Solid coding practices (clean, testable, automated) The mindset of a builder: thrives in fast-paced startup environments, takes ownership, solves complex challenges Bonus points if you've worked with: large-scale data processing, ETL pipelines, cloud deployments, or DevOps/CI-CD practices. Why join? Competitive salary + benefits Ownership and impact in a high-growth cybersecurity scale-up Work with cutting-edge technology and some of the brightest minds in the industry Fast-tracked career growth with internal progression opportunities Remote-first culture with the best tools and kit to succeed This is more than a backend engineering role - it's a chance to be part of a team building technology that helps some of the world's largest enterprises stay ahead of attackers. Interested? Let's talk - this one won't be around for long.

Senior Full Stack Engineer Cybersecurity Scale-Up Fully Remote (Global) Want to use your full stack skills to help stop real-world cyber attacks? This is your chance to join a fast-growing, VC-backed cybersecurity innovator , recognised by Gartner and trusted by Fortune 500s and critical infrastructure providers worldwide. They're building cutting-edge technology that helps organisations continuously understand how they could be compromised - and they're scaling fast. Now, they're looking for a Senior Full Stack Engineer to join their Client Facing Applications (CFA) team, where you'll help shape the customer experience for some of the world's largest enterprises. What you'll be doing: Designing and developing enterprise-grade SaaS features across backend and frontend systems Building secure, scalable, and high-performing APIs and services (NestJS, GraphQL, REST) Creating data-driven dashboards and UIs with React, Next.js, and Chakra UI Translating product and design requirements into elegant, maintainable solutions Troubleshooting and optimising performance across the full stack Collaborating with product managers, designers, and engineers to deliver seamless client experiences Driving continuous improvements in engineering practices, tooling, and processes What they're looking for: 5+ years' experience building enterprise SaaS products (ideally in cybersecurity or data-heavy environments) Strong backend development with TypeScript, NestJS, Sequelize ORM, GraphQL, REST APIs Frontend expertise with ReactJS, NextJS, Typescript, Chakra UI Experience with MySQL and NoSQL databases Familiarity with messaging/event-driven systems (Kafka) Ability to work closely with designers (Figma) and translate complex business logic into intuitive UI/UX Problem-solver with strong debugging, troubleshooting, and optimisation skills Thrives in high-growth startup/scale-up environments, with adaptability and ownership mindset Bonus points if you have: AWS or Kubernetes experience Workflow engine knowledge (Xstate, Argo Workflows) Broader understanding of networking and infrastructure Why join? Competitive compensation & benefits A key role in a high-growth cybersecurity scale-up solving global challenges Cutting-edge tools and kit to help you succeed Endless growth opportunities - internal promotion is core to their culture Collaborate with cybersecurity experts and work on problems that really matter This isn't just another engineering role. It's your chance to build technology that protects enterprises from real-world attacks while shaping the future of offensive security at scale. Interested? Apply now - this one won't stay open for long.

Senior Java Developer - Leeds City Centre (Hybrid) Up to £60,000 4 Days in Office, Friday WFH AI & Machine Learning I'm recruiting for a forward-thinking tech company based in Leeds City Centre that's transforming how retailers harness AI and machine learning to boost profitability and stay competitive in a rapidly evolving market. They're looking for an experienced Senior Java Developer to join their talented team of 7 engineers, reporting directly to the Engineering Manager. You'll play a pivotal role in developing intelligent, data-driven software used by major retail clients across the UK, Europe, North America, and Australia. The Opportunity This is a hands-on senior role - ideal for someone who thrives on technical challenges, loves solving complex problems, and wants to build systems that make a tangible business impact. You'll be working closely with data scientists and product specialists to deliver scalable, high-performance software solutions that integrate the latest AI and ML technologies. Tech Stack & Tools Essential Skills: 8+ years' experience in Java development (commercial) Strong expertise in Spring / Spring Boot Solid experience with Hibernate Desirable Skills: Python or R - exposure to data or ML integration SQL - for data management and optimisation JavaScript - for front-end collaboration Grails - nice to have, not essential Environment & Tools: Cloud: AWS / Azure DevOps: Git, CI/CD, Docker, Kubernetes Agile, collaborative environment with code reviews and shared ownership What You'll Be Doing Designing and developing enterprise-grade Java applications using Spring and Hibernate Collaborating with data scientists to embed AI/ML insights into real-world systems Building scalable, high-availability solutions for global retail clients Driving code quality, performance, and architecture best practices Mentoring junior engineers and contributing to continuous improvement What We're Looking For 8+ years' experience in Java software development Proven background delivering complex, scalable backend systems Deep understanding of Spring Boot and Hibernate Familiarity with cloud-based environments (AWS or Azure) Strong communicator and team player Able to work 4 days on-site in Leeds City Centre, with Friday working from home What's on Offer Up to £60,000 Hybrid working - 4 days in the office, Friday from home Global exposure - clients across the UK, Europe, North America & Australia Work with cutting-edge AI and machine learning technologies Collaborative, supportive team of 7 developers Career growth opportunities with direct access to the Engineering Manager Oscar Associates (UK) Limited is acting as an Employment Agency in relation to this vacancy. To understand more about what we do with your data please review our privacy policy in the privacy section of the Oscar website.

Location: UK Remote Salary: £65 000 - £75 000 Sector: Full Stack Developer Type: Permanent We're looking for a Senior Full Stack Engineer to help shape and deliver innovative features for SaaS platforms. You'll work across the stack, contributing to both front-end and back-end development, ensuring a seamless user experience while maintaining technical excellence. This role involves close collaboration with Delivery Managers, Product Managers, and other Senior Engineers, as well as providing technical leadership to ensure high-quality, scalable solutions. Key Responsibilities: Deliver high-quality features for SaaS products, working across both front-end and back-end technologies. Provide technical leadership and support team members to deliver dependable estimates and evolve best practices. Collaborate with senior stakeholders to refine and execute the technical roadmap. Contribute to building a strong developer community by sharing knowledge and driving best practices. Actively participate in sprint planning and execution. Document technical approaches with a focus on testing, CI/CD, and scalability. Key Requirements: Frontend: Experience with React, Redux, and TypeScript. Backend: Expertise in Node.js microservices and familiarity with REST, GraphQL, asynchronous messaging, and JSON. Proficiency with NoSQL databases (e.g. MongoDB) and search technologies (e.g. Elasticsearch or Atlas Search). Strong understanding of automated testing, CI/CD pipelines, and integration/unit testing. Excellent communication, leadership, and mentoring skills in a remote, collaborative environment. Pragmatic problem-solving skills and adaptability to change. Passion for personal growth and improving ways of working. Desirable Skills: Familiarity with AWS services (SNS/SQS, S3, CloudFormation) and DevOps principles. Experience with Docker, AWS ECS, or Kubernetes. Knowledge of modern frontend frameworks/tools such as Vite and Next.js. Experience with end-to-end testing tools like Cypress. Backend frameworks such as Express and Apollo Server. Agile methodology experience in a fast-paced SaaS environment. Understanding of configuring scalable and customizable features for enterprise clients.