14 systems integration developer jobs found in London

Senior NetSuite Developer £500 - £550 per day (Outside IR35) This freelance opportunity offers the chance to lead complex NetSuite transformation programmes across multi-entity, international environments. You will take ownership of end-to-end solution design and delivery, working closely with senior stakeholders to shape scalable NetSuite architectures that support long-term business transformation. The Company They are a global organisation operating across multiple regions and business units, undergoing significant systems and process transformation. NetSuite sits at the centre of their finance and operational landscape, supporting growth, optimisation, and integration across the wider technology estate. The environment is complex, fast-moving, and collaborative, with a strong focus on long-term platform value. The Role and Deliverables Lead end-to-end NetSuite solution architecture and delivery across multi-entity and multi-country implementations. Run discovery...

KDB Developer - Outside IR35 Contract London, UK - Hybrid Working Up to £800 per day Long-Term Engagement on a Rolling Contract May Start Date Our client, a leader in the FinTech space are searching for a KDB Developer to add to their Client Engineering team! You'll be working alongside Software teams to develop, test and maintain all code for client applications. Responsibilities will include : Gather and translate business requirements into technical solutions for market data and analytics applications Design, develop, test and maintain kdb+ applications and supporting services Support full project delivery lifecycle, including debugging, optimisation and production support Perform data analysis and build reporting/analytics outputs for stakeholders Mentor junior developers and contribute to code quality, standards and team delivery Technical Skills needed : Hands-on experience with kdb+ and strong proficiency in q for time-series data...

Frontend Developer Remote with very occasional client visits £400pd - Outside IR35 6 - 8 month contract Primarily Remote - occasional on-site presence at Lisburn (paid for) Our client, an established and successful Technology company are looking for an experienced Frontend Developer to join them on a contract basis They are an industry leading Smart technology company with clients around the globe such as Claridges, Nobu and Belgravia You will be working on a critical-infrastructure platform being developed at Belfast Hospital, currently in a UK Government commercial and financial audit. The work is React component build against a published 1,300-line developer build specification, with an established design system, audit-log integration requirement, and live data feeds We are looking for: Expert knowledge of React and TypeScript Comfort working alongside AI-assisted development tools. The internal team works with AI tooling in daily development; you must...

Senior NetSuite Developer £500 - £550 per day (Outside IR35) This freelance opportunity offers the chance to lead complex NetSuite transformation programmes across multi-entity, international environments. You will take ownership of end-to-end solution design and delivery, working closely with senior stakeholders to shape scalable NetSuite architectures that support long-term business transformation. The Company They are a global organisation operating across multiple regions and business units, undergoing significant systems and process transformation. NetSuite sits at the centre of their finance and operational landscape, supporting growth, optimisation, and integration across the wider technology estate. The environment is complex, fast-moving, and collaborative, with a strong focus on long-term platform value. The Role and Deliverables Lead end-to-end NetSuite solution architecture and delivery across multi-entity and...

Role: Data and AI Tech Lead Role Type: Outside IR35 Contract Rate: Negotiable Location: London, UK - Hybrid (Hybrid 1 or 2 Days Onsite a week) Note: No of positions 1. Role Overview: We are seeking a Data & AI Technical Lead to drive the Discovery & Design phase of a large-scale M&A program for a Retail & CPG client. This role will lead the technical direction across a complex, multi-cloud data landscape spanning Azure, AWS, GCP, Databricks, and Snowflake. You will oversee and guide senior Data Architects, ensuring architectural alignment, technical quality, and business relevance. The role sits at the intersection of business strategy, data architecture, and platform engineering, acting as a key liaison between client stakeholders, IT teams, and the Chief Data Office. This is a high-impact leadership role requiring both hands-on architectural depth and stakeholder influence at senior levels. Key Responsibilities: 1. Technical...

Salesforce Developer 6-12 month Contract London (Hybrid, 2 days a week in the office) £300-£350 per day outside IR35 I'm currently working with a well-known not-for-profit organisation looking to hire a Salesforce Developer to play a key role in a complex CRM migration, helping to shape and enhance a growing Salesforce environment within a mission-driven organisation. The role would suit someone with strong hands-on Salesforce development experience, who enjoys building scalable solutions, developing integrations, and working closely with stakeholders to deliver impactful platform improvements. The Salesforce Developer will: Design, develop, and implement custom Salesforce solutions across the platform Build and maintain Apex, Lightning Components, Flows, and integrations with third-party systems Collaborate with Business Analysts and stakeholders to translate requirements into scalable technical solutions Support the ongoing optimisation and enhancement of the...

Salesforce Developer 6-12 month Contract London (Hybrid, 2 days a week in the office) £300-£350 per day outside IR35 I’m currently working with a well-known not-for-profit organisation looking to hire a Salesforce Developer to play a key role in a complex CRM migration, helping to shape and enhance a growing Salesforce environment within a mission-driven organisation. The role would suit someone with strong hands-on Salesforce development experience, who enjoys building scalable solutions, developing integrations, and working closely with stakeholders to deliver impactful platform improvements. The Salesforce Developer will: Design, develop, and implement custom Salesforce solutions across the platform Build and maintain Apex, Lightning Components, Flows, and integrations with third-party systems Collaborate with Business Analysts and stakeholders to translate requirements into scalable technical solutions Support the ongoing optimisation and...

Salesforce Developer 6-12 month Contract London (Hybrid, 2 days a week in the office) £300-£350 per day outside IR35 I'm currently working with a well-known not-for-profit organisation looking to hire a Salesforce Developer to play a key role in a complex CRM migration, helping to shape and enhance a growing Salesforce environment within a mission-driven organisation. The role would suit someone with strong hands-on Salesforce development experience, who enjoys building scalable solutions, developing integrations, and working closely with stakeholders to deliver impactful platform improvements. The Salesforce Developer will: * Design, develop, and implement custom Salesforce solutions across the platform * Build and maintain Apex, Lightning Components, Flows, and integrations with third-party systems * Collaborate with Business Analysts and stakeholders to translate requirements into scalable technical solutions * Support the ongoing optimisation and enhancement of...

Salesforce Developer 6-12 month Contract London (Hybrid, 2 days a week in the office) £300- £350 per day outside IR35 I 'm currently working with a well-known not-for-profit organisation looking to hire a Salesforce Developer to play a key role in a complex CRM migration, helping to shape and enhance a growing Salesforce environment within a mission-driven organisation. The role would suit someone with strong hands-on Salesforce development experience, who enjoys building scalable solutions, developing integrations, and working closely with stakeholders to deliver impactful platform improvements. The Salesforce Developer will: * Design, develop, and implement custom Salesforce solutions across the platform * Build and maintain Apex, Lightning Components, Flows, and integrations with third-party systems * Collaborate with Business Analysts and stakeholders to translate requirements into scalable technical solutions * Support the ongoing...

Senior .NET / Full Stack Developer – Hybrid – £500/day Outside IR35 | C# | Azure | Event-Driven Systems | Payments | API-Driven We have a unique opportunity for a Senior .NET / Full Stack Developer to join a payments company. As a Senior .NET / Full Stack Developer , you’ll play a key role in building and scaling a high-throughput payments platform as the business enters its next phase of growth. This includes launching new products, enabling new partner integrations, and expanding a platform that already powers multiple live financial services products used globally. You’ll be building on top of a modern, cloud-native platform built with .NET and Azure , designed around API-first architecture and event-driven microservices . The platform supports complex payment flows, partner integrations, and high-volume transaction processing. This is a hands-on senior engineering role where you’ll contribute to architectural discussions, drive engineering best...

About BigHand BigHand offers technology solutions for busy legal professionals that provide data and insights to increase value and profits. Through our expert knowledge and innovative technology, we enable our customers to achieve enhanced efficiency, better decision-making and harness their competitive edge. We build with tomorrow in mind, transforming ideas into action and empowering our customers to succeed in a world of constant change. We make big happen for our customers. We are a business driven by our values and have these at the centre of everything we do. Our BigHanders are dedicated to building a culture where We Win Together, We Love to Learn, We Do the Right Thing, We Own It and We Find the Fun. About the role We're looking for 4 Azure DevOps Consultants to work on a greenfield AI transformation programme. Building Azure cloud services from scratch, you will actively promote DevOps ways of working and SRE best practices within teams. Work...

Business Analyst (Microsoft Dynamics CRM) Location: Hybrid - London or Northampton Contract: 9 months (Initial) Rate: £330 per day (Outside IR35) Start Date: ASAP Only candidates with housing experience and Microsoft Dynamics CRM will be considered for this position. Overview Endeavour Recruitment is working on behalf of a housing client seeking an experienced Business Analyst to support a newly developed Asset Management System built on Microsoft Dynamics CRM. The successful candidate will play a key role across multiple projects, focusing on integration, compliance, and ensuring effective system interconnectivity. Key Responsibilities Work across multiple concurrent projects within the asset management and systems landscape Gather, analyse, and document business and technical requirements Support system integration initiatives across platforms Ensure compliance requirements are accurately captured and implemented Collaborate with stakeholders across business...

Opening: Join the Mission We deliver secure, mission‑critical platforms and services for government and regulated organisation’s operating in high‑assurance environments. Our teams work at the intersection of cloud engineering, DevSecOps, and platform enablement, helping organisation’s adopt Google Distributed Cloud (air‑gapped GCP). This role offers the opportunity to shape automation‑first testing strategies for new cloud‑native platforms, influence tooling and quality standards, and ensure solutions are secure, resilient, compliant, and testable by design. Role Purpose As an Automation Test Engineer, you will be responsible for designing, building, and operating automated testing capabilities across platform and application delivery teams. You will: Define and implement test automation strategies aligned to IaC, CI/CD, and DevSecOps practices Select, evaluate, and trade‑off test tooling suitable for air‑gapped Google Distributed Cloud environments Build and...

Lead C# Engineer - Agentic Workflows & Native AI Engineering, .Net 8/9, AWS (Lambda, SQS) – OUTSIDE IR35 Reporting to the Director of Engineering, this is a genuinely outstanding contract opportunity for a rockstar Senior C# Engineer to lead the development of a greenfield SaaS product . We’re looking for a ‘best of breed’, deeply senior, technically hands-on engineer who thrives in complex problem spaces and fast-moving start-up & scale-up environments. You’ll need a genuinely Product Centric mindset and approach twinned with experience of AI-Native Engineering and Agentic Workflow . Skills We’re Looking For: Senior–Staff-level backend engineer with deep, current expertise in C# and .NET Core 8/9 , capable of architecting and leading the design of distributed REST API microservices at scale. Authority in AWS serverless architecture; Lambda-first, with strong working knowledge of API Gateway, SQS, Step Functions, EventBridge and IAM, and...