1 to 25 of 35 Permanent JSON Jobs in London

Quality Assurance Engineer

Hiring Organisation
Harnham
Location
London Area, United Kingdom
such as HTML, CSS and JavaScript. • Hands‐on experience with tools such as Selenium, Playwright or similar automation frameworks. • Solid understanding of API testing, JSON/XML formats and tools such as Postman or Swagger. • Familiarity with CI/CD pipelines and version control. • Comfortable working in data‐rich environments ...

Mid-Senior Ruby on Rails Engineer (B2B SaaS | Hybrid | UK)

Hiring Organisation
Transreport
Location
London Area, United Kingdom
experience with PostgreSQL, including performance tuning and complex queries. Experience with background job processing using Sidekiq and Redis. Solid understanding of RESTful API design, JSON serialization, and authentication (e.g., JWT, SSO). Hands-on experience with AWS services and containerised deployments (Docker). Experience troubleshooting and supporting production systems. Comfortable ...

QA Automation Engineer

Hiring Organisation
Harnham - Data & Analytics Recruitment
Location
London, South East, England, United Kingdom
Employment Type
Full-Time
Salary
£60,000 - £65,000 per annum
building UI tests with tools such as Selenium or Playwright. * Working knowledge of test frameworks such as JUnit or TestNG. * Understanding of APIs, HTTP, JSON and related testing tools. * Comfortable working in data-rich environments and validating data accuracy. * Experience using AI tools within your engineering workflow to accelerate development ...

Java Architect (with Capital Markets)

Hiring Organisation
DXC Technology
Location
City of London, London, United Kingdom
optimizing SQL queries on PostgreSQL databases. Strong experience with multithreading, data structures, and concurrency scenarios. Proficient in using REST APIs, XML, JAXB, and JSON in creating layered systems. Experience with AWS Services (AWS Lambda, AWS CloudWatch, API Gateway, ECS, ECR, SQS, SNS). Familiarity with Open AI APIs, Agentic ...

DevOps / Cloud Engineer

Hiring Organisation
Lynx Recruitment Ltd
Location
London, South East, England, United Kingdom
Employment Type
Full-Time
Salary
Salary negotiable
serverless technologies (e.g. AWS Lambda, API Gateway) Solid knowledge of Linux-based systems Ability to write code/scripts (ideally Python, plus YAML/JSON) Experience working with distributed, enterprise-level systems Strong communication skills and ability to work with stakeholders Additional Desirable Skills Experience with tools such as Ansible ...

Lead Solution Architect Endur (ETRM Gas & Power Trading)

Hiring Organisation
BP Energy
Location
South West London, London, United Kingdom
Employment Type
Work From Home
services (strongly preferred) and cloud-native patterns C# or Java Containerisation (Kubernetes/Docker/OpenShift) Infrastructure as code (Terraform) Integration and messaging (APIs, JSON/Swagger/OpenAPI, AMQ or similar) CI/CD and DevOps tooling; Git-based workflows Nice to have Endur modernisation experience (e.g., upgrades, cloud ...

Front End React Developer

Hiring Organisation
Ascend Consulting
Location
NW7, Mill Hill, Greater London, United Kingdom
Employment Type
Permanent
Salary
£45000 - £75000/annum Great Benefits
core principles Experience with Redux and RTK (RTKQuery also a bonus) Familiarity with RESTful APIs Knowledge of modern authorization mechanisms, such as JSON Web Token Familiarity with modern front-end build pipelines and tools (Github actions a bonus) Experience with common front-end development tools such as Babel, Webpack ...

Senior AI Engineer

Hiring Organisation
Harnham
Location
City of London, London, United Kingdom
first products that deliver measurable value. • Develop and deploy production‐grade AI agents on GCP using ADK, integrating with internal systems via REST and JSON APIs. • Build and maintain robust evaluation and monitoring frameworks, including online and offline testing, A/B experiments and performance dashboards. • Integrate AI agent functionality ...

Head of Software Engineering

Hiring Organisation
Jobleads-UK
Location
Greater London, England, United Kingdom
asset security protocols. Technical Experience: Experience designing/leading a team that is API-forward and has built distributed scalable,systemsusingOpenJDK, Gradle,Intellij,Postgresql, JSON, JUnit, Quartz, JWT, JOOQ, Liquibase, Docker, Kubernetes, AWS Cloud Stack, Confluentand more. Hands-on experience with modern engineering tools and practices (e.g., Kubernetes, microservices ...

Network Automation Engineers

Hiring Organisation
Tech Mahindra
Location
London, United Kingdom
Employment Type
Permanent
Salary
£60000 - £75000/annum
Cisco NSO – Service development and lifecycle Apache Airflow Hasi Corp Vault Openshift Automation development Python Fast API Rest API Netconf Yang modelling XML/Json Jinja/TextFSM Pytest Unit testing Database MongoDB DevOps Docker Git CI/CD Kubernetes Networking Ciena 517x/8180/8114 Nokia BNG/ ...

Java Developer Contract

Hiring Organisation
Atrium (EMEA)
Location
London Area, United Kingdom
tools such as Apache Spark or in this instance LakeFS, for data processing and management. Useful: R, Apache Spark Very Useful: Python, SQL, JSON, LakeFS ...

Senior Data Modeller

Hiring Organisation
Harnham - Data & Analytics Recruitment
Location
London, South East, England, United Kingdom
Employment Type
Full-Time
Salary
£80,000 - £88,000 per annum
migration/transformation programmes* Expertise across conceptual, logical, and physical modelling* Strong stakeholder management skills* Experience working in Agile environments* Knowledge of UML, RDBMS, JSON/XML* Knowledge/experience of Erwin Desirable: * Knowledge of industry data standards (e.g. fpML, FIX, FIBO)* Experience with ontologies (RDF/OWL/ ...

Systems Integration Engineer | E-commerce | Shopify | Fully Remote | £280 Outside IR35

Hiring Organisation
VirtueTech Recruitment Group
Location
City of London, London, United Kingdom
integration environments Strong API integration experience (Shopify, Magento, SAP, Oracle etc.) Experience integrating with ERP, OMS & PIM systems Knowledge of integration methods (API, EDI, JSON, XML, streaming) Familiarity with AWS, SQL & analytics/reporting tools Experience working in Agile environments Strong problem-solving & stakeholder management skills 🌟 This is a high ...

Systems Integration Engineer | E-commerce | Shopify | Fully Remote | £280 Outside IR35

Hiring Organisation
VirtueTech Recruitment Group
Location
East London, London, United Kingdom
integration environments Strong API integration experience (Shopify, Magento, SAP, Oracle etc.) Experience integrating with ERP, OMS & PIM systems Knowledge of integration methods (API, EDI, JSON, XML, streaming) Familiarity with AWS, SQL & analytics/reporting tools Experience working in Agile environments Strong problem-solving & stakeholder management skills 🌟 This is a high ...

Java Developer – Market Connectivity

Hiring Organisation
Solytics Partners
Location
City of London, London, United Kingdom
Platform. Experience with electronic market protocols: FIX (4.x/5.x) Market-specific APIs (Tradeweb, Bloomberg, MTS, etc.) Binary/Streaming protocols (ITCH, FAST, SBE, JSON over TCP). Familiarity with low-latency patterns, high-throughput messaging, and microservices. Additional Skills Experience with Linux, shell scripting, and performance analysis tools. Knowledge ...

Lead AI Automation Engineer

Hiring Organisation
PaymentGenes
Location
City of London, London, United Kingdom
reporting Build event-driven workflows across email, Teams, APIs, and databases Architect Agent Systems Modular task decomposition Guardrails and validation layers Structured output validation (JSON schemas, rule checks) Logging, observability, fallback logic, and confidence scoring Secure credential and secrets management Governance & Scale Ensure explainability and traceability Design compliant automation aligned ...

Head of Engineering

Hiring Organisation
Zeus® | AI-Powered Logistics
Location
London Area, United Kingdom
/S/4HANA patterns), TMS, WMS, carrier/telematics platforms, customer master systems Own integration architecture across: Inbound/outbound APIs (REST/JSON), event-driven messaging (queues/topics), batch feeds, file-based interfaces (S3-based exchanges), structured email fallbacks Demonstrate practical experience with API management and integration ...

Guidewire Integration Lead - £800/day inside - 9 months

Hiring Organisation
Hawksworth
Location
City of London, London, United Kingdom
10+ years of Guidewire Integration development experience Proven experience leading integration teams (PolicyCenter, BillingCenter, ClaimCenter). Java, Gosu; REST/SOAP Web Services; XML, JSON Integration Gateway, Cloud API, Batch/Async processing Agile/Scrum delivery environments and using JIRA. Desirable, but not essential.. Guidewire ACE certified integration specialist ...

Ruby on Rails Backend Engineer

Hiring Organisation
Rise Technical Recruitment
Location
Fulham, London, United Kingdom
Employment Type
Permanent
Salary
£60000 - £80000/annum Private Healthcare + Holiday + Pensi
Rails developer with deep expertise in PostgreSQL and background processing via Sidekiq and Redis. You should be highly proficient in building RESTful APIs, managing JSON serialisation, and implementing secure authentication methods like JWT or SSO. Beyond coding, you will possess knowledge of Docker and AWS, alongside the communication skills required ...

GTM Engineer

Hiring Organisation
Loctax
Location
City of London, London, United Kingdom
APIs (Claude, GPT, etc.) programmatically from application code. You will build workers that use AI for classification, scoring, and reasoning — constructing structured prompts, parsing JSON responses, handling errors, and managing the boundary between what the AI decides and what the code enforces. This is not prompt engineering in a chat ...

Principal Solutions Consultant

Hiring Organisation
Jobleads-UK
Location
Greater London, England, United Kingdom
customer experience platforms.* 3+ years leading large, strategic, and complex enterprise deals.* Deep technical fluency with web/scripting technologies (HTML, CSS, JavaScript, JSON, LLMs, MCP) and SaaS architectures.* Proven success in positioning the business value of technical solutions and the strategic role of Professional Services and Partners.* Hands ...

PKI Engineer

Hiring Organisation
Lorien
Location
London Area, United Kingdom
OpenSSH, Kubernetes and service mesh certificate architectures (mTLS, SPIFFE/SPIRE style identities). Proficiency with scripting and automation (Python, PowerShell, Bash, Go, JSON) and IaC tools (Azure DevOps, Terraform, Ansible). Experience modernising TLS certificate and SSH key management processes, uplifting protocol versions, and improving trust configurations. Knowledge ...

DocuSign & SharePoint Integration Specialist (Microsoft 365/APIs)

Hiring Organisation
Rothstein Recruitment Ltd
Location
London, United Kingdom
Employment Type
Any
Salary
GBP Annual
would be beneficial. Interested? Please Apply! DocuSign, DocuSign CLM, eSignature, DocuSign Administrator, SharePoint Online, Microsoft 365, M365, Microsoft Graph API, REST API, APIs, Webhooks, JSON, OAuth, Azure, Azure Functions, Logic Apps, API Integration, System Integration, Workflow Automation, Document Management, Contract Lifecycle Management, Salesforce integration, Power Automate, Power Apps, Nintex ...

Senior/Principal Data Modeller

Hiring Organisation
Harnham - Data & Analytics Recruitment
Location
London, South East, England, United Kingdom
Employment Type
Full-Time
Salary
£70,000 - £90,000 per annum
migrations. Shape and document metadata, lineage, catalogues and source-to-target mapping. Contribute to ETL design and data movement patterns across platforms. Work with JSON, XML, Parquet and other semi-structured formats used across financial systems. Engage senior stakeholders and guide best practice within multidisciplinary teams. Principal level: provide thought ...

Solution Consultant

Hiring Organisation
Mirakl
Location
London, England, United Kingdom
with a track record of leading design sessions and crafting detailed, technical solutions for SaaS platforms You are familiar with web technologies and frameworks (JSON/XML, CSV, Responsive Design, Restful APIs). Fluency in English. We welcome collaborators with their diverse perspectives and experiences to power us forward. These ...