JavaScript / API Engineer

JavaScript/API EngineerAre you passionate about revolutionizing capitalism and supporting noble causes? Do you enjoy crafting innovative products that can significantly impact people's lives?At Percent, we aspire to build a world where doing good is effortless. Our inaugural mission is to channel 1% of global retail spending towards charitable initiatives.With our third round of funding secured to turn this vision into reality, we are searching for an exceptional JavaScript/API Engineer to join our enthusiastic team. You will play a pivotal role in developing an array of remarkable features for our key stakeholders, including some of the largest charitable organizations globally.We offer:A supportive and enjoyable team environmentA strong focus on people and collaborationA substantial and impactful projectA modern office located in central LondonDelicious company lunches every TuesdayAn opportunity to address global challenges while maintaining a positive mindsetA creative and unconventional work cultureYou should possess:A passion for contributing to a better worldA willingness to take shared ownership of a significant projectStrong proficiency in Object-Oriented JavaScript and Node.jsExperience with various database technologiesCapability to handle high-volume API calls and scale solutions globallyUnderstanding of networking protocolsFamiliarity with numerous AWS servicesKnowledge of network configurationsExperience with monitoring systems, continuous integration, and testingA creative and unconventional approachAdditionally, while not mandatory, it would be beneficial to have knowledge of:Serverless architectures (AWS Lambda)HTTP/2Containerization technologiesVideo streaming solutionsInfrastructure as codeA fondness for tea breaksWe provide:Competitive compensation for the right candidate along with excellent equity optionsAn opportunity to become a partner in our missionA prime location in Soho/PiccadillyA highly comfortable workspaceFresh fruit every day (or biscuits for those with a sweet tooth)A fully stocked luxury coffee and tea machine available at all times

Role Overview Legal & General Group is hiring an Engineering Manager with deep experience in Typescript and Javascript. This position is based in London and focuses on guiding a skilled engineering team to deliver strong technical solutions for clients. What You Will Do Lead and support a team of engineers working with Typescript and Javascript Oversee project schedules and ensure milestones are met Mentor junior engineers and help them grow their skills Work closely with other teams to deliver solutions that fit client needs About Legal & General Group Legal & General Group is committed to building strong engineering practices and values leaders who bring both technical expertise and a collaborative approach.

xai seeks a Backend Engineer in London, UK to focus on API development. This role involves designing and building APIs that form the backbone of the company’s products and services. Key responsibilities Design and implement APIs to support xai’s solutions Collaborate with frontend developers and product managers to ensure seamless feature integration Optimize API performance and maintain reliability This position offers the chance to work closely with both technical and product teams, shaping the way xai’s services communicate and perform.

Role overview Wise seeks an Engineering Lead to focus on API experience in London. The role involves leading a team that designs and builds API solutions for customers at scale. This position centers on both technical leadership and team guidance. What you will do Guide and support engineers as they develop Wise’s API products Encourage new ideas and drive technical improvements within the team Oversee the creation and maintenance of scalable, reliable APIs Work to ensure Wise APIs align with customer needs and meet industry standards Location This position is based in London.

Join us in revolutionizing travel!Travel is more than just a journey; it connects us with loved ones, opens up new adventures, and creates unforgettable experiences. Yet, the frustrations of travel can often overshadow the excitement. Over 4 billion airline passengers depend on outdated technology that fails to meet the expectations of today's connected traveler.At Duffel, we are on a transformative mission to modernize the travel infrastructure. We aim to simplify complex systems and develop innovative tools that ensure a seamless travel experience for everyone.As part of the Y Combinator S18 cohort, we are proudly backed by notable investors including Benchmark, Blossom, Index Ventures, and Kima Ventures, who have played a pivotal role in the growth of some of the world’s leading companies.Position OverviewIf you are passionate about customer success and excel at solving intricate technical challenges, this is the perfect opportunity for you. Duffel is seeking a Customer Success Engineer (CSE) to deliver expert technical support to our key clients. In this role, you'll assist customers by answering their inquiries and recommending effective ways to leverage our APIs to create outstanding travel experiences. Furthermore, you will work closely with various teams across Duffel, including Product, Engineering, Finance, and Travel Operations, to guarantee an exceptional customer journey with our products and services.

Corgi is an AI-driven insurance company serving tech startups. After raising $108 million and becoming a licensed carrier, Corgi is expanding into the UK and EU. The platform relies on Django, Stripe for payments, and AI-powered underwriting to simplify the insurance process. Role overview The JavaScript Engineer role is based in London. Corgi values engineers who can build and launch products independently, without waiting for detailed project plans. Candidates who have shipped side projects, weekend builds, or live products used by real people will stand out. What we look for Motivated, energetic engineers comfortable in a startup setting Evidence of independently developed and launched projects Ability to deliver results quickly, often in hours or days Comfort working across the stack and tackling a range of technical challenges Strong opinions balanced with openness to feedback and change Low-ego approach, focused on outcomes rather than titles How we work Decisions are made quickly, not delayed for perfect solutions New products and improvements launch regularly, not just quarterly We ship and iterate, avoiding drawn-out review cycles Energy stays high during launches and quieter periods alike Transparency guides decision-making; no private backchannels Top performers raise the bar for the whole team This position is for doers who want to make an impact, not those looking to coast. Behaviors that will end employment Office politics, blame-shifting, or gossip Taking feedback personally instead of using it to improve Adding unnecessary complexity instead of simplifying Missing deadlines after committing to them How to apply Send links to your GitHub, personal website, live projects, or shipped products Do not send a CV Email applications to: sergio@corgi.com If you cannot provide evidence of shipped work, this role is not a fit Location and compensation Based in London; on-site and hybrid options available Base salary: £75,000 to £140,000, plus equity Salary depends on proven ability to ship, not job title

Role overview Wise is hiring an Engineering Lead to guide the API Experience Team in London. This position centers on building and refining API services that enable smooth integration and support reliable user experiences. The Engineering Lead manages a talented group of engineers and collaborates with teams across Wise to strengthen API products. What you will do Lead and mentor the API Experience engineering team Oversee the development and improvement of API services Work closely with teams from different functions to enhance product offerings Promote solutions that simplify integration for Wise’s partners and users

Join ClearBank as an API Integration Analyst and play a pivotal role in enhancing our banking solutions through seamless API integrations. You will work closely with cross-functional teams to analyze, design, and implement integration solutions that meet our clients' needs. This is a fantastic opportunity for someone who is passionate about technology and its application in the financial sector.

About UsAt Perlego, we are a dedicated team of nearly 100 professionals striving to democratize education. We believe that access to high-quality, affordable learning materials is essential for unlocking potential. Knowledge should be readily available, free from exorbitant costs.Over the last seven years, we have focused on empowering students across the UK and Europe to enjoy access to quality books. Following our recent $20 million funding round, we are excited to expand our reach to students globally, particularly in the US, while developing a platform that transcends traditional books, enabling students to study more effectively.Position OverviewWe are seeking a talented Software Engineer with proficiency in JavaScript, React, NextJS, Node.js, TypeScript, AWS, and Test-Driven Development (TDD). You will become a key member of our learner Tribe, collaborating within a squad dedicated to leveraging data-driven insights to enhance our technical SEO initiatives, improving the experience for logged-out users and optimizing payment subscription processes for our direct-to-consumer customers.Working EnvironmentOur teams operate in cross-functional squads, all focused on achieving common data-driven objectives. This role will join a squad made up of 4 Engineers, an Engineering Manager, a Data Engineer, a QA Engineer, a Designer, and a Product Manager.Technology Stack:NextJSReactTypeScriptNode.jsAWSPreferred Qualifications:Experience with Stripe payment systemsFamiliarity with Optimizely A/B testing toolsKey QualificationsYou are a great fit if you possess:A solid background in developing high-performance web applications using JavaScript, React/NextJS, Node.js, and TypeScript.A deep understanding of architectural principles such as Microservices, REST, object-oriented, and functional programming, as well as relational and NoSQL database design.Extensive experience with AWS and other cloud computing platforms.Expertise in modern JavaScript development techniques and tools.Experience in ideation and executing A/B tests to assess the impact of various features and monetization strategies.Experience working in an Agile environment emphasizing Test-Driven Development and CI/CD practices.Commercial experience as a software engineer.The ability to communicate complex technical issues in a simplified manner to non-technical stakeholders.⭐ Bonus Points If You Have:A degree in a computing-related field.Experience in technical SEO or payment-related projects.Experience in a startup setting.

Join the dynamic team at Sony Interactive Entertainment Global as a Senior Software Engineer specializing in Rendering API. In this pivotal role, you will be responsible for developing and optimizing rendering technologies that enhance the gaming experience for millions of users worldwide. You will collaborate closely with cross-functional teams to bring innovative solutions to life, ensuring top-notch performance and visual fidelity in our gaming products.

Join Us in Revolutionizing Travel!Travel is an integral part of life, whether it’s to reconnect with loved ones, embark on thrilling adventures, or attend significant business engagements. Unfortunately, many travelers face challenges due to outdated technology. Over 4 billion airline passengers depend on systems that fail to meet the expectations of the modern, connected traveler.At Duffel, we are on a mission to transform the travel industry by rebuilding its infrastructure. Our goal is to simplify complex systems and create innovative tools that make travel seamless and enjoyable.As a proud participant of Y Combinator's S18 cohort, we are backed by leading investors such as Benchmark, Blossom, Index Ventures, and Kima Ventures, who have supported the growth of some of the world’s largest companies.We are seeking a passionate Customer Success Engineer (CSE) to provide exceptional technical support to our key customers. In this role, you will address customer inquiries, guide them in utilizing our APIs effectively, and collaborate with various departments including Product, Engineering, Finance, and Travel Operations to enhance the overall customer experience.

Join our dynamic team as a Senior JavaScript Automation Developer where you'll have the opportunity to work fully remote and outside of IR35 regulations. With a competitive daily rate of up to £400, this role requires you to leverage your extensive expertise in test automation and JavaScript programming.Your responsibilities will include:Joining an Agile development team focused on Front End and API development.Creating comprehensive test automation suites using JavaScript.Implementing BDD principles with tools like Cucumber and TestCafe.Collaborating with clients, analysts, and engineers throughout the software development lifecycle.Supporting test cycle execution, tracking defects, and providing test results to clients.

Join our innovative team at version1 as a Senior JavaScript Developer, where you'll play a vital role in developing high-quality web applications. You will be responsible for designing, implementing, and maintaining complex software solutions using the latest technologies. If you are passionate about coding and thrive in a collaborative environment, we want to hear from you!

We are seeking a talented Apigee Application Developer to join our dynamic team in London or Swindon. The ideal candidate will have expertise in Apigee, Java, and JavaScript, and will play a pivotal role in delivering RESTful APIs as part of our agile development team.Key Responsibilities:Actively participate in the development of RESTful API solutions as an Apigee Developer.Deliver high-quality code in Java and JavaScript from often ambiguous requirements.Adhere to stringent coding standards, including unit testing and deployment practices.Mentor junior developers and engage in peer code reviews.Demonstrate a proven track record in Java-based project delivery, utilizing tools such as Maven, Git, and Eclipse.Familiarity with PaaS platforms, NoSQL databases, and microservices architecture is a plus.

At Flowdesk, we are on a mission to establish a global financial institution for digital assets, meticulously crafted to foster market integrity and enhance efficiency.In a swiftly evolving market landscape, we employ a disciplined, first-principles methodology in all our operations. This approach is woven into our core services, including institutional liquidity provision, trading solutions, OTC execution, and extensive treasury management services. By adhering to these principles, we navigate the complexities of the financial world, constructing robust and scalable systems across our diverse business lines.We invite individuals who share our passion for systematic approaches to join us in revolutionizing the financial markets infrastructure to be more transparent and efficient.Our APIs serve as the gateway for external trading interactions, and we are excited to announce an opening for a Senior Software Engineer – API Trading. In this role, you will design, develop, and scale our public trading APIs to a competitive standard. You will take ownership of the API surface that clients integrate with (REST, WebSocket, FIX), ensuring it is clear, well-documented, and collaborates closely with trading, product, and security teams to deliver a best-in-class experience.This is a hands-on, senior individual contributor role that emphasizes technical ownership and cross-team collaboration.Your mission will involve:Designing and building competitive trading APIsArchitecting and implementing public trading APIs (REST, WebSocket, and FIX) using Rust.Ensuring low-latency and high-throughput access to trading workflows including orders, balances, positions, and executions.Owning the API lifecycle from start to finishDefining and maintaining OpenAPI specifications and related interface contracts.Keeping APIs consistent, versioned, and simple for external client integration.Creating clear, accurate, and engaging API documentation that developers will find valuable.Building secure and robust authentication flowsDesigning and implementing authentication and authorization for public trading APIs.Applying best practices for key management, signatures, rate limiting, replay protection, and preventing abuse.Collaborating across trading, product, and engineering teamsWorking closely with stakeholders to understand trading needs and constraints.Translating trading and product requirements into clean API designs and dependable backend workflows.Partnering with frontend and tooling teams (TypeScript) to ensure seamless integration.Raising the bar on reliability and qualityEnsuring APIs are observable, thoroughly tested, and resilient under peak loads.Contributing to the development of standards, patterns, and tools for API development across the team.Mentoring team members and participating in code reviews.

Role overview Ebury Partners UK Limited is seeking a Senior Product Manager to lead its API Platform in London. This position shapes the company’s API strategy and drives execution, working with teams throughout the business to enhance and grow product capabilities. What you will do Direct the development of API products that align with business goals and client requirements. Collaborate with engineering, design, and commercial teams to launch new features and refine existing ones. Prioritize projects and initiatives, drawing on product management experience to deliver results on schedule. Leverage expertise in API technologies to spot opportunities for improvement and innovation. Requirements Solid track record in product management, particularly with API platforms or similar technologies. Strong communicator with experience working across multiple teams. Skilled at turning client needs into actionable product solutions. This role is based in London. Ebury is a fintech company dedicated to building solutions that help clients advance their business.

Join Tripadvisor as a Solution Architect specializing in Viator API Implementation!In this pivotal role, you will:Partner Enablement & Solution Design:Work alongside B2C platforms, OTAs, and travel e-commerce partners to assess their business goals and technical specifications.Design comprehensive solutions utilizing Viator’s APIs tailored to meet partner requirements, aiming to enhance their commercial success.Offer expert advice on API functionalities and best practices that boost conversion rates.Assist partners in crafting an implementation roadmap, providing support pre and post-development to leverage Viator's API effectively for business growth.Collaborate closely with Viator’s product, engineering, and business development teams to ensure partner feedback drives continual improvement of our API offerings.Technical Leadership:Act as the primary technical liaison for partners during the API integration phase.Conduct API demonstrations to empower partner teams.Identify and resolve technical challenges, providing solutions to facilitate smooth integrations.Help partners enhance the performance of Viator’s APIs to ensure scalability and optimal user experience.

Role overview Ebury is seeking a Group Product Manager to lead API Connectivity from its London office. This position sets the direction for API-driven products, focusing on features that simplify integration for both clients and partners. The work centers on shaping product strategy and ensuring smooth execution for API connectivity across the platform. What you will do Define and drive the vision and roadmap for API connectivity throughout Ebury’s platform Collaborate with engineering, design, and commercial teams to deliver new API features Spot opportunities to enhance integration and improve the client experience Guide product evolution to address changing client needs Collaboration This role works closely with teams across the business to strengthen and expand Ebury’s API offerings. Regular interaction with stakeholders is part of the job, ensuring priorities stay aligned and the API products deliver clear value.

Convera is hiring a Product Marketing Manager focused on Partnerships and API Solutions, based in London. This position centers on shaping and delivering marketing strategies that support both partner relationships and API-driven products. Role overview The Product Marketing Manager will take the lead in planning and executing campaigns to strengthen Convera’s partnerships and promote API solutions. Working closely with teams across the company, this role aims to increase product adoption and deepen customer engagement. Key responsibilities Develop and implement marketing strategies for partnerships and API offerings Collaborate with cross-functional teams to align product messaging and positioning Drive initiatives that encourage product adoption and ongoing client engagement Collaboration This role involves regular coordination with product, sales, and client success teams to ensure that solutions align with client needs and market demands.

Join the innovative team at Difrent Group, a leader in digital transformation within government and healthcare sectors. We are currently seeking a talented and experienced Automation Tester to join our specialist team on a contract basis. This role provides an exciting opportunity to contribute to high-profile digital transformation projects for our public sector clients.As an Automation Tester, you will play a crucial role in ensuring the functionality and performance of our products. Your primary responsibility will be to validate that all systems and their interfaces meet specified requirements before release.To excel in this position, candidates should possess robust knowledge in functional, API, automation, and performance testing. Experience within an Agile environment, including participation in stand-ups and sprints, is also essential.