Senior Software Engineer - Transforming Music Technology

Innovative Music Technology - On-Demand Vinyl ProductionJoin elasticstage as a Senior Software Engineer and be part of a revolution in the music industry. We have developed a groundbreaking technology that allows for the production of on-demand vinyl records and created a web platform that empowers music creators to effortlessly create and sell their product…

Stacks is hiring an Interim Recruiter for a full-time contract based in London. This position runs for 3 to 6 months and centers on scaling Go-To-Market (GTM) teams, including Sales, Marketing, Customer Success, and Implementation. The team values in-person collaboration, working primarily from the London office to encourage teamwork and spark new ideas. Role overview This contract role calls for an experienced recruiter who can manage commercial hiring from start to finish. The Interim Recruiter will partner closely with hiring managers, keep multiple searches on track, and ensure candidates have a positive experience throughout the process. Building strong pipelines and refining hiring processes are central to this position. Main responsibilities Lead end-to-end recruitment for GTM roles (Sales, Marketing, Customer Success, Implementation) Handle several open positions at once, balancing speed and quality Build candidate pipelines through sourcing, outreach, referrals, and networking Oversee screening, assessment, and candidate management through to offer stage Work with hiring managers to define needs and set hiring priorities Coordinate interviews, feedback, and decision timelines Share market insights and regular updates on pipelines with stakeholders Maintain a high standard of candidate experience Identify and approach top commercial talent across the UK and Europe Establish immediate pipelines for current roles and anticipate future needs Provide insights on competitor hiring trends, compensation, and talent availability Work environment This role is office-first in London. Stacks believes close teamwork drives progress and values the energy of in-person collaboration.

Join Us in Revolutionizing the Fashion Supply Chain!Every year, the fashion industry generates over 100 billion garments, with a staggering 60% ending up in landfills—not due to lack of demand, but because the supply chain for secondhand fashion is outdated and inefficient.At Fleek, we are committed to changing this narrative. Our mission is to position secondhand fashion as the preferred choice, by developing a robust infrastructure that supports the global secondhand clothing market through a B2B marketplace and AI-driven systems that digitize the supply chain.With Fleek, vintage shops, online resellers, and retail buyers can source high-quality secondhand inventory directly from wholesalers and rag houses across various countries. Our innovative solution, FleekSort, is an AI model specifically designed for secondhand fashion, enabling grading, pricing, and categorization of items with just a photo, transforming an opaque and manual trade into a clear, searchable, and tradable global inventory.Since our inception in 2022, we have rescued 9 million items from landfills and have seen our growth triple year-on-year. We have successfully raised approximately $50M from leading investors such as a16z, Y Combinator, Burda Principal Investments, and HV Capital, and recently completed our Series B funding round. Our advisors and private investors include key figures from Depop, Shopify, and Postmates.Currently, we cater to thousands of resellers and retailers across the UK, Europe, and the US. With projections of the secondhand fashion market reaching $350B by 2027, Fleek is poised to establish the AI-powered operational and financial backbone for global secondhand commerce.Are you ready to contribute to a cause that truly matters and drive change swiftly? If so, we want to hear from you!About the RoleWe are on the lookout for a highly technical and innovative Full-Stack Growth Builder who will redefine how customer lifecycle marketing propels growth at Fleek. This role transcends traditional CRM responsibilities; you will design and implement the entire system from data collection to strategic execution, making AI your primary toolkit.Your responsibilities will include creating intelligent CRM systems that identify the optimal timing, channel, and messaging for customer outreach, utilizing real-time user signals and context. You will also establish robust experimentation frameworks to accurately measure the impact of lifecycle messaging while avoiding over-attribution. Furthermore, you will spearhead the use of AI-driven content generation and personalization, ensuring a balance between scalability, quality, and relevance.As we scale our marketplace from thousands to tens of thousands of active buyers, you will be instrumental in building our data infrastructure in real-time.

Join our innovative team at EnableAll, where we are dedicated to enhancing web accessibility through our cutting-edge B2B SaaS solutions. We are seeking a skilled Full Stack Developer to contribute to our pioneering web accessibility application powered by AI. You will play a crucial role in helping eCommerce businesses comply with global accessibility standards such as ADA, EAA, and WCAG, ultimately fostering inclusivity and increasing conversions.As a pivotal member of our small but ambitious team, you will be involved in building and maintaining a modern, scalable SaaS platform, currently launched on the Shopify App Store, with plans for expansion across various eCommerce and CMS ecosystems.This role will allow you to engage in a true product engineering experience, tackling complex technical challenges while delivering a reliable platform that serves a diverse range of eCommerce brands.

Location: London, UK (hybrid) Role Type: Full-time Join our innovative team at Materiom as a Senior Software Engineer. In this pivotal role, you will engage in the rapid prototyping, development, and productization of data-driven and AI-centric web applications. Your contributions will play a vital role in overcoming R&D challenges for pioneers in bio-based materials. You will be tasked with designing and building robust full-stack systems, making significant architectural contributions, and translating complex user needs into actionable technical strategies. You will also champion engineering best practices within our mission-driven startup culture. Your technical prowess across the stack, particularly on the front end, combined with a product-focused approach, will ensure the delivery of high-impact results. As you design user-centric applications, you will transform prototypes into actionable solutions that propel Materiom’s mission forward. Collaborating closely with Materiom's senior leadership team, including the Co-CEOs and CTO, you will be instrumental in shaping our product and platform. #python #fastapi #react #typescript #GCP #PostgresSQL

We are seeking a talented Full Stack Developer to join our dynamic team at Vitol, where you will collaborate closely with various business lines. This role presents a unique opportunity to engage with both technical and non-technical experts to create innovative solutions and full-stack applications that are utilized globally across numerous commercial and operational desks. Your contributions will significantly influence decision-making through the development of cutting-edge solutions.In this role, you will play an integral part in transforming our existing application landscape. Your ability to swiftly comprehend business needs, communicate effectively, work autonomously, and rapidly prototype and iterate on new and existing requirements will be essential in delivering state-of-the-art solutions that empower our commercial teams.As a Full Stack Developer at Vitol, you will exemplify:Rapid Prototyping: Collaborate closely with operations and commercial teams to construct and support market-driven business development applications and enhance existing tools by swiftly iterating based on user feedback to create actionable, value-adding solutions.Project Management: Analyze ongoing business and user requirements while independently managing project lifecycles from start to finish within the team.Innovation: Propose innovative and reliable technical solutions that enhance existing processes or uncover new opportunities for the business.Platform Expertise and Integration: Develop a comprehensive understanding of Vitol's Management Information Systems (MIS) platforms and tools, including their functionalities and capabilities, to ensure their success.

Full Stack Developer with PHP Symfony Expertise - LondonWe are seeking a talented Full Stack Developer with experience in PHP Symfony to join our client, a prominent provider in the arts sector located in central London. This is an exciting opportunity to contribute to projects that are both technically robust and visually captivating.As a Full Stack Developer, you will engage in the entire project lifecycle, bringing innovative ideas to fruition. You will thrive in dynamic digital environments, addressing complex challenges with creative solutions.

Corgi builds insurance products for tech startups, using AI to streamline underwriting and improve the customer experience. With $108 million in funding and a carrier license, the company is growing rapidly and expanding into the UK and EU. The core platform is built with Django, integrates Stripe for payments, and relies on AI-driven processes. Role overview This Full-Stack Developer position is based in London. The role is designed for people who enjoy taking ownership of projects from concept to launch, often working independently or in small teams. Corgi values developers who have shipped real products, whether as side projects, weekend builds, or tools with active users. What you will do Own projects from idea through live deployment, frequently working solo or in small groups Work across the stack, adapting quickly to new technical challenges Contribute to a workflow focused on frequent shipping and iteration Participate in open, transparent decision-making Maintain steady progress during both launch sprints and quieter periods What Corgi looks for Proven experience delivering shipped projects independently Comfort with the pace and ambiguity typical of startups A bias toward action and results Strong technical opinions, balanced with openness to better ideas Low-ego, outcome-focused approach How the team works Quick decisions are valued over waiting for perfect answers Products and processes are updated frequently, not just on a set schedule Short review cycles and a focus on shipping improvements High intensity during launches, steady progress at other times Transparent, public-first communication style Internal competition motivates high performers This is a build-focused role where sustained contribution and ownership are important. Behaviors that will lead to quick removal Office politics, blame-shifting, or gossip Taking feedback personally rather than constructively Adding unnecessary overhead or slowing down processes Missing deadlines after making commitments How to apply Send links to your GitHub, personal website, or live projects you have shipped Do not send a CV Email applications to: sergio@corgi.com If you cannot provide evidence of shipped work, this role is unlikely to be a fit Location and compensation Based in London, with on-site and hybrid options Base salary: £75,000 to £140,000, plus equity The salary range reflects Corgi’s focus on proven ability to ship, not job titles

Join our client, a prominent arts venue situated in the vibrant heart of London, as an accomplished Full Stack Developer specializing in PHP Symfony2. This exciting opportunity allows you to contribute your expertise to a team dedicated to creating projects that are both technologically advanced and visually stunning.In your role as a Full Stack Developer, you will oversee projects from their inception through to their completion, ensuring they meet the highest standards of quality and innovation. Your ability to navigate complex digital landscapes will be invaluable.

Full Stack Developer - Immediate Start The OpportunityAt Zero One Creative, we are revolutionizing the creative landscape with Amara, our state-of-the-art AI platform that seamlessly converts natural language into immersive 3D environments. As a Full Stack Developer, you will play a pivotal role in creating the web interface that connects creators to our advanced AI engine.Here's how it works:Start ASAP on a paid 1-week sprint (£500), collaborating with our dedicated team on the core web platform development.Demonstrate your exceptional skills to secure a permanent position with a competitive salary ranging from $80,000 to $100,000.This is not just a trial; it’s a high-impact sprint aimed at delivering production-ready systems. The ChallengeJoin us in building the full-stack platform that powers Amara. You will design user-facing systems that manage everything from user authentication to real-time AI-driven generation, thereby enabling creators to oversee their projects and interact with AI in real time.Your sprint deliverable: Features that are not only production-ready but also showcase scalable architecture, clean API design, real-time functionality, and robust front-end implementation.What You'll be BuildingHelp construct a platform that democratizes AI-powered 3D creation:Core Features - User authentication, project management, and data organization functionalities.Real-Time Interfaces - WebSocket-driven UIs that provide live feedback and responsive controls.Backend Services - FastAPI microservices effectively managing core platform logic and AI interactions.Cloud Infrastructure - Collaborate with our cloud engineer to develop a scalable AWS deployment, incorporating storage, caching, and CI/CD pipelines.Your contributions will connect users to our AI systems, forming the reliable platform layer essential for accessibility.You're Our Ideal Candidate If You Have: Frontend Mastery - Proficient in React + TypeScript, with experience in state management and real-time WebSocket clients. Backend Expertise - Skilled in Python (FastAPI), PostgreSQL, Redis, and Authentication & Security protocols like OAuth2 / JWT, with experience in scalable async services. Problem-Solving Mindset - A proactive approach to tackling challenges head-on.

Role Overview Position: Senior Full Stack Developer (Java/React) with Security Clearance Eligibility Location: London, UK (Hybrid – 1 to 2 days per month in the office) Contract Type: Permanent, Full-time Compensation: £70,000 - £80,000 base salary, plus 10% bonus, 10% equity, and benefits About Appvia Appvia delivers consultancy in cloud, platform, and solutions engineering. The company helps organizations modernize software systems, improve developer productivity, and adopt cloud-native methods for sustainable delivery. Appvia works on complex, high-impact projects across public and private sectors, focusing on quality, scalability, and reliability. Areas of expertise include modern application development, domain-driven design, and optimizing architecture and testing for better delivery outcomes. What You Will Do Senior Full Stack Developers at Appvia join a growing software engineering team, supporting a large modernization and AI-driven transformation project. The work is hands-on and client-facing, involving the design and implementation of modern software solutions in complex environments. Projects often involve building new systems within existing legacy landscapes, introducing new architecture, tools, and engineering standards for long-term scalability. This role reports to a Principal Software Engineer and contributes to both project delivery and the ongoing development of Appvia’s engineering practice. Requirements Eligible for UK Security Clearance (SC), which requires: British Passport or Indefinite Leave to Remain (ILR) Residency in the UK for the past five years No criminal record or financial irregularities Extensive experience with React and modern front-end development Strong back-end development skills with Java (Spring Boot) Knowledge of Domain Driven Design (DDD) Experience working with microservices architecture Full-stack experience across UI, API, and data layers Background in cloud-native environments, preferably AWS Interest or experience in AI-assisted development to boost productivity and quality Comfort working directly with stakeholders and guiding teams Interview Process Initial discovery conversation with Talent Acquisition Technical interview with the Engineering Team Final interview with Leadership

At Synthesia, we are redefining the future of communication through our leading AI video platform, embraced by over 90% of Fortune 100 companies. Established in 2017 and headquartered in London, our presence spans across Europe and the United States, with a diverse team dedicated to innovation.As the AI landscape evolves, we are committed to enhancing visual communication and fostering enterprise skill development, ensuring that individuals are empowered to excel and remain integral to the success of their organizations.After a successful Series E funding round that secured $200 million, our valuation has reached $4 billion, with total funding exceeding $530 million from esteemed investors like Accel, NVentures (Nvidia's venture capital), Kleiner Perkins, GV, and Evantic Capital, as well as founders and executives from Stripe, Datadog, Miro, and Webflow.About the RoleYou will take on an end-to-end role, contributing to our client application built in React and our robust monolithic backend developed in Python, while ensuring secure feature releases to our customer base.You will own long-term projects that require breaking down complex challenges into manageable, iterative steps for delivery and validation.Collaboration with the product manager will be key, allowing you to ideate solutions focused on commercial problems and shape product direction.Your work will be evaluated through established data pipelines and frameworks to assess the impact of your features on our business objectives, enabling you to pivot as needed.You will also be tasked with considering the team's long-term direction, ensuring we build the engineering capabilities necessary to tackle future challenges over the next 6-12 months. What We're Looking For:A minimum of seven (7) years of experience in software engineering, with at least 3 years in a senior or lead role.Experience in a high-performing engineering team, whether in a scale-up environment or an established organization recognized for its outstanding engineering culture.Strong capability across the tech stack, with in-depth knowledge of server-side development and backend technologies. Backend-focused experience is acceptable if you're willing to assist on the frontend occasionally.Proficiency in relevant engineering practices and tools that enhance productivity and performance.

Join stacks as a Product Marketing Manager in London! In this dynamic role, you will lead the marketing strategy for our innovative products, working closely with cross-functional teams to ensure our offerings resonate with target audiences. You will be responsible for conducting market research, developing compelling marketing campaigns, and analyzing performance metrics to drive growth.

Join Stacks, a dynamic and innovative company at the forefront of growth marketing. We are seeking a passionate Growth Marketer who will play a pivotal role in driving our marketing strategies and initiatives. You will be responsible for developing, executing, and optimizing campaigns that attract and retain customers, leveraging data-driven insights to enhance our market presence.As a Growth Marketer, you will collaborate closely with cross-functional teams to identify growth opportunities and implement effective marketing tactics. Your creativity and analytical mindset will be key in designing engaging content and utilizing various digital channels to reach our target audience.

We are seeking a talented Full Stack Web Developer to join our dynamic team at Ratio Recruitment Ltd. This is an exciting opportunity to work on innovative projects that are shaping the future of technology.The ideal candidate will be proficient in both front-end and back-end development, capable of delivering high-quality code and user experiences. You will work closely with cross-functional teams to design and implement robust web applications.

This position is available in our Amsterdam or London office.We are committed to an office-first culture, believing that collaboration fosters the creation of exceptional products.About StacksAt Stacks, we are revolutionizing how finance teams manage one of their most essential processes: the monthly close. For mid to large enterprises, this process is often labor-intensive, diverting finance teams from strategic initiatives to focus on monotonous tasks. We believe it’s time for a change.Our ambitious vision is to leverage AI to make the monthly close as simple as a single click—delivering precise and comprehensive financial insights from the very first day of the month. By reclaiming valuable time for finance teams, we empower them to concentrate on high-impact, strategic endeavors that propel their organizations forward.Our team comprises finance, product, and tech experts from esteemed companies like Uber, Plaid, Miro, Mollie, and Bunq. United by a common goal of creating a transformative solution, we operate from a stunning office that overlooks the iconic canals of Amsterdam. Supported by prominent VCs and leaders from Stripe, Plaid, and OpenAI, we are poised to redefine the future of finance.About the RoleWe are seeking a highly ambitious, entrepreneurial, and commercially savvy Customer Success Manager - Accounting to join our team as one of our inaugural Customer Success hires.In this influential role, you will help shape and implement our go-to-market strategy at Stacks. If you thrive in dynamic environments and are excited by the prospect of limitless growth, this is a unique opportunity to fast-track your career while helping to shape the future of Stacks. Your ResponsibilitiesEnhance Customer Success: Manage the entire customer lifecycle from onboarding to renewal and expansion. You’ll engage directly with Controllers, Finance leaders, and CFOs to ensure that Stacks becomes an indispensable asset in their accounting operations.Accounting-Focused Support: Utilize your accounting expertise to thoroughly understand customer workflows and challenges. You’ll provide guidance based on your financial close experience, helping clients maximize their use of Stacks.Boost Net Retention: You will take ownership of renewals and expansions within your portfolio by delivering measurable value and fostering strong relationships.

ClaimSorted supports insurers with a combination of in-house expertise and an AI-powered platform. The company’s Third-Party Administration service manages over $100 million in insurance premiums for more than 30 Managing General Agents, including several publicly listed organizations. With backing from Y Combinator, Atomico, and Eurazeo, ClaimSorted has raised over $15 million and aims to scale to $1 billion in managed premiums. Role overview As a Forward Deployed Engineer in London, work directly with customers and internal teams to deliver solutions that improve claims management and operational processes. This role involves both technical development and close collaboration with stakeholders at all levels. What you will do Work alongside customer stakeholders, ranging from technical staff to executive leadership. Build and maintain systems that support customer operations and make onboarding more efficient. Provide accurate reporting and insights to both customers and colleagues. Translate customer feedback into meaningful platform enhancements. Technology stack NextJS NodeJs Google Cloud Platform (GCP) Postgres Terraform Location This position is based in London.

Senior Product EngineerAbout the PositionCaribou is seeking a talented and experienced Senior Product Engineer to elevate our product team. This key role demands a full-stack engineer with a strong product intuition and proven history of transforming innovative ideas into successful products from inception to launch.As we harness the latest in AI and LLM technology, your expertise in these areas will be crucial. You should be well-versed in contemporary techniques and capable of building independently, even in the absence of a dedicated design team.Your primary responsibility will be to translate raw business objectives into impactful customer-facing features, ensuring a top-tier customer experience. You will guide the entire product development lifecycle, from understanding real user issues to crafting thoughtful solutions and implementing them across our technology stack.This position intersects engineering, product development, AI, and design. Collaborating closely with founders and cross-functional teams, you will tackle ambiguous challenges and deliver elegant, scalable solutions that enhance our customer experience.Your ResponsibilitiesLead the full-stack development of new product features from initial concept through to production deployment.Engage in product discovery: analyze customer feedback, map user workflows, identify opportunities, and prioritize feature development.Utilize AI and LLMs to enhance product capabilities, streamline development processes, and innovate complex tax workflows.Work alongside the tax team to deeply understand user needs and translate them into actionable product enhancements.Make informed decisions regarding infrastructure and architecture to ensure high-performance, reliable feature delivery.Enhance code quality by writing maintainable code, contributing to design systems, and refining engineering practices.Job Requirements5+ years of experience as a full-stack or product-focused engineer in a web application startup environment.Strong technical proficiency in modern front-end frameworks and back-end technologies.

Join Synthesia, the premier AI video platform revolutionizing business communication, trusted by over 90% of Fortune 100 companies. Since our inception in 2017, we've grown into a global leader, headquartered in London with teams across Europe and the US.As AI continues to redefine our professional landscape, Synthesia is at the forefront, crafting innovative products that enhance visual communication and foster enterprise skill development, empowering individuals to excel within their organizations.Following our successful Series E funding round, securing $200 million, we are now valued at an impressive $4 billion, with total funding exceeding $530 million from top-tier investors, including Accel, NVentures (the venture arm of Nvidia), Kleiner Perkins, GV, and Evantic Capital, alongside founders and operators from Stripe, Datadog, Miro, and Webflow.About the RoleIn this role, you will engage in end-to-end development, contributing to our client application built in React and our monolithic backend in Python, ensuring the seamless and safe deployment of your features to our user base.You will take full ownership of long-term projects, adeptly breaking down complex challenges into manageable steps that can be iteratively delivered and validated.You will collaborate directly with the product manager to brainstorm and focus on the commercial challenges you are addressing, giving you a significant role in shaping the product's trajectory.Utilizing our established data pipeline and frameworks, you will assess the impact of your work on our business objectives and adjust your approach as necessary.You will contribute to the long-term strategy of the team, ensuring we develop the engineering capabilities required to tackle future challenges over the next 6-12 months.

Join Runna as a Senior Software Engineer II, where you'll play a pivotal role in enhancing our software solutions. You will collaborate with cross-functional teams to design, develop, and implement robust applications that meet our customers' needs. Your expertise will help us push the boundaries of technology, ensuring our products remain at the forefront of the industry.