Join Anyone AI, where we're on the lookout for talented Full-Stack Developers to collaborate on innovative projects with a leading AI laboratory. This is an exciting opportunity to be at the forefront of AI technology.

About Stack AIStack AI is on a mission to make Large Language Models accessible to everyone through an intuitive no-code platform that seamlessly integrates leading AI models (OpenAI, Anthropic, Google), various data sources (OneDrive, Google Drive, Notion), and essential SaaS tools. With the backing of Y Combinator and Gradient Ventures, we have amassed thousands of users and secured hundreds of paying clients, including prominent public companies and unicorns.The RoleWe are seeking a talented Senior Frontend Engineer who excels in execution. This role focuses on optimizing and enhancing existing features rather than creating flashy new ones. You will collaborate closely with our Product Design team to transform detailed visual specifications into clean, production-ready code.Main Mission: Alleviate bottlenecks within our Product Design team by taking charge of incremental UX/UI enhancements to our current features and codebase.What You'll DoOptimize and enhance existing frontend code and features.Implement gradual UX/UI enhancements based on detailed design specifications (no design skills required).Work independently with minimal code review—your code should be clean and dependable enough for others to trust without hesitation.Collaborate with Product Designers and Engineers to ensure effective execution.Focus on impactful improvements that enhance product quality and user experience.Refactor and improve legacy code.What We're Looking ForMust-haves:Exceptional code quality: Produce clean, maintainable, and trustworthy code that requires minimal review.Strong execution: Ability to ship quickly and effectively.Senior-level experience: Over 5 years of experience with React, TypeScript, Next.js, and modern frontend technologies.Accountability: You take ownership of your decisions and act responsively.Autonomy: You can manage features from start to finish without needing guidance.Pragmatism: You are ready to engage in detail-oriented, iterative work critical to product success.Technical excellence: A mentor who can share knowledge rather than someone who needs to be taught.Nice-to-haves:Experience with additional frameworks or tools.Familiarity with agile methodologies.Passion for user experience and design.

Role Overview anyone-ai is looking for a Backend Developer - AI Trainer based in Spain. This role focuses on building and improving backend systems that support AI training projects. What You Will Do Develop and refine backend infrastructure to support AI model training and deployment. Work closely with team members to optimize systems for real-world AI applications. Contribute technical expertise to help strengthen the performance and reliability of AI models. Collaboration Work alongside a group of professionals committed to advancing AI technology. Teamwork and knowledge sharing are central to this position.

Anyone AI seeks experienced Backend Developers based in Spain to support a high-profile AI laboratory project. This remote, part-time role centers on expert evaluation tasks and the creation of realistic software engineering exercises. Role overview As a Backend Developer - AI Trainer, the primary focus is on designing and assessing complex coding challenges. Tasks include bug fixes, feature development, refactoring, migrations, and test generation. The position involves both creating coding scenarios and reviewing peer submissions for accuracy and quality. Responsibilities Design and implement multi-file coding assignments covering bug resolution, new features, refactoring, and testing Write clear, natural-language specifications and provide reference implementations Develop and improve unit and integration test suites Review and evaluate peer-generated tasks for correctness, clarity, and realism Identify edge cases, ambiguities, and potential failure points Ensure alignment between specifications, code, and expected results Requirements Exceptional written English skills 3–7 years of experience in software engineering Advanced proficiency in Python and JavaScript or TypeScript; familiarity with Java, C#, or Go is a plus Background in backend or full-stack development within production settings Knowledge of testing frameworks such as pytest, Jest, JUnit, xUnit, or Go testing Strong debugging skills and the ability to navigate large, multi-file codebases Experience with code reviews, refactoring, and production migrations Engagement details Part-time, project-based work Remote from anywhere in Spain Expected outcomes Deliver high-quality, production-ready coding tasks that meet industry standards

Role overview Anyone AI seeks experienced software engineers to serve as AI Software Engineering Trainers. This is a remote, part-time consulting position for candidates based in Spain. Trainers collaborate with a prominent AI laboratory, shaping authentic engineering tasks and evaluating solutions for technical quality and depth. What you will do Create and implement multi-file coding challenges that cover bug fixes, new features, refactoring, and test development. Write clear, thorough specifications along with reference implementations. Develop and expand unit and integration test suites. Review peer-created tasks for technical accuracy and clarity. Identify edge cases, ambiguities, and potential failure points in both code and requirements. Ensure alignment between specifications, code, and expected outputs. Expected outcomes Deliver solutions that are production-ready and meet recognized industry standards. Requirements Exceptional written English for professional communication. 3 to 7 years of hands-on software engineering experience. Proficiency in Python and JavaScript or TypeScript. Knowledge of Java, C#, or Go is a plus. Background in backend or full-stack development for production environments. Experience with testing frameworks such as pytest, Jest, JUnit, xUnit, or Go testing tools. Ability to work with large, multi-file codebases and debug complex issues. Track record of code reviews, refactoring, and managing production migrations. Engagement details Part-time, project-based consulting arrangement. Fully remote role based in Spain.

Groupon, Inc. is seeking an AI Full-Stack Developer to join the team in either Madrid or Prague. The position centers on building and integrating artificial intelligence features throughout the technology stack, helping connect millions of consumers with local businesses around the globe. Key responsibilities Design and implement solutions that incorporate AI technologies into both front-end and back-end systems Collaborate with fellow developers to achieve seamless integration and dependable performance Suggest and develop improvements that enhance user experiences and make business operations more efficient through artificial intelligence Location This role is based in Madrid or Prague.

Role overview psicro seeks a Full-stack Developer in Madrid to support the development of AI-driven software products. This position covers both front-end and back-end responsibilities, contributing throughout the software development lifecycle. What you will do Build and maintain features for AI solutions, handling both client-side and server-side tasks Work closely with colleagues from various backgrounds to deliver dependable software Turn client requirements into scalable, maintainable technical solutions Requirements Background with modern web technologies and frameworks Strong teamwork and clear communication skills Interest in artificial intelligence and its real-world uses This role is located in Madrid.

GenLayer Labs – Barcelona (Hybrid)Join us at GenLayer Labs, a pioneering decentralized AI research collective that is revolutionizing the trust infrastructure for the AI Age. We are the creators of GenLayer—an innovative, AI-driven Court of the Internet, a synthetic jurisdiction where autonomous agents and protocols can reason, transact, and govern at machine speed with unparalleled sovereignty, transparency, and trust. Our cutting-edge infrastructure empowers autonomous agents and smart contracts to access real-time web data, interpret natural language, and resolve disputes through AI consensus.Backed by industry leaders like Maelstrom (Arthur Hayes), Arrington Capital, and North Island Ventures, we are forging a new paradigm of decentralized infrastructure focused on trustless decision-making for the AI era.Role OverviewWe are on the lookout for an AI-First Developer / Builder who is eager to explore and create prototypes, tools, and internal systems that expand the potential of intelligent contracts and AI-enabled infrastructure.You will work closely with a compact, talented technical team in a dynamic AI-assisted development environment, utilizing tools such as Claude Code, OpenClaw, and other agent-based workflows to drive rapid exploration and development.This role is perfect for someone who: Thrives on rapid development. Is adaptable to ambiguity and experimentation. Integrates AI agents into their daily workflow. Is passionate about working with innovative AI and blockchain technologies.Your Responsibilities Develop AI-driven tools, prototypes, and internal systems. Create Python backends and APIs for AI-enhanced features. Work with LLMs, agents, and RAG pipelines. Prototype AI-assisted developer workflows. Experiment with novel AI capabilities for intelligent contracts. Design small full-stack applications (backend and simple frontend). Utilize AI copilots and agents extensively in development. Collaborate closely with a small team to rapidly test and iterate on ideas.

jobgether is looking for a Senior Full Stack Engineer based in Spain. This role centers on building and maintaining both front-end and back-end systems that support the company’s job search platform. Role overview As a Senior Full Stack Engineer, the focus will be on designing, developing, and supporting applications that deliver a smooth and responsive user experience. The position involves working across the technology stack to ensure applications perform reliably and efficiently. What you will do Design and implement features for both front-end and back-end systems Maintain and improve application performance and responsiveness Work with cross-functional teams to deliver software that meets user needs Requirements Strong background in software development Proficiency in multiple programming languages Solid understanding of web technologies This position supports jobgether’s mission to simplify job searching by delivering reliable and user-friendly software solutions.

Join our innovative technical team at Septeo, where artificial intelligence serves as a true co-pilot in development. Your role will encompass:Designing and developing responsive front-end applications with Angular, utilizing tools like Copilot and Gemini to accelerate component creation and enhance quality.Implementing robust back-end solutions using .NET Core and C#, adhering to best practices and generating tests with assistance.Leveraging AI for:Generating unit and integration tests.Refactoring and optimizing performance.Security validation and early bug detection.Integrating and maintaining secure payment gateways.Designing and optimizing databases in SQL Server.Containerization with Docker and deployment on Azure.Participating in CI/CD processes and intelligent automation.Creating functional and technical documentation supported by AI tools.

Role Overview Miratech is looking for a Senior Full Stack Developer with strong experience in Java and Angular. This position is based in València. What You Will Do Develop web applications using Java and Angular Enhance and maintain existing platforms Collaborate with cross-functional teams to deliver software that meets client requirements

Join anyone-ai as an AI Software Engineering Trainer, where you will play a pivotal role in shaping the future of AI education. Your expertise in software engineering and AI technologies will help guide aspiring professionals in mastering cutting-edge methodologies.As part of our innovative team, you will be responsible for developing and delivering training programs, creating engaging content, and mentoring participants to achieve their career goals in AI.

Join Groupon, a leading marketplace where customers explore new experiences and services daily, and where local businesses thrive. We have partnered with over a million merchants worldwide, connecting more than 16 million customers with deals across diverse categories. In a landscape often dominated by e-commerce giants, Groupon stands out as one of the few platforms genuinely committed to propelling local businesses forward based on performance.We are on an exciting journey to radically transform our business through a relentless focus on results. Despite having thousands of employees across multiple continents, we foster a culture that inspires innovation, rewards risk-taking, and celebrates success. Here, your impact can be immediate due to our scale and the rapid pace of our transformation. We blend the best of both worlds: we have the resources and scale of a large company, yet we empower individuals to have significant autonomy and drive meaningful change.About the RoleHybrid from Madrid or ValenciaAs a Full Stack AI Engineer, you will engineer the foundation of our proprietary internal platform that democratizes AI across the organization. This role goes beyond standard full-stack duties; you will construct the framework that enables various teams to develop autonomous AI agents. Your responsibilities will include designing reasoning flows, integration layers, and agent logic that empower AI to execute complex business tasks at scale. This is applied AI engineering: focusing on sophisticated system design and relentless execution rather than model fine-tuning. You will collaborate daily with a newly formed team of engineers and work closely with the AIGO team and cross-functional partners across Global Operations, Customer Satisfaction, and Engineering.

Key Responsibilities- Design the architecture of web pages based on provided layouts.- Develop reusable code for future projects.- Implement mobile-first design principles to ensure optimal user experience on smartphones.- Monitor and enhance website performance for speed and scalability.- Exhibit self-management skills and effectively prioritize tasks.Essential Qualifications- Proficiency in Laravel, PHP, MySQL, HTML5, CSS3, JavaScript, Sass, Git, VueJS, and TailwindCSS.- Minimum of 3-5 years of proven experience in PHP Laravel, HTML, CSS, and JavaScript development.- Deep understanding of SCSS and Blade templates (Laravel).- Familiarity with VueJS, AMP, and TailwindCSS is preferred.- Experience in responsive and adaptive design methodologies.- Knowledge of SEO best practices.- Proven experience with collaborative version control systems.- Background in an agile team environment.- Excellent English communication skills, both verbal and written.- Strong grasp of Object-Oriented design principles and methodologies.- Experience with databases, including relational and NoSQL databases.- Competence in integrating third-party APIs and libraries.- Experience with search servers (e.g., Elastic or Algolia) is a plus, but not mandatory.- If you have a GitHub account or have contributed to open-source projects, we'd love to hear about it in your cover letter.

Are you passionate about the Spanish language and ready to influence the future of artificial intelligence? As AI technology evolves, large-scale language models are transforming from simple chatbots into sophisticated tools for linguistic exploration. By providing high-quality training data, we can enable AI to facilitate world-class education, enhance modern research, and improve communication for Spanish speakers globally. Your expertise is crucial in this evolution—we invite you to be a part of it!We are seeking Spanish (Spain) language specialists with an in-depth understanding of phonetics, morphology, syntax, semantics, pragmatics, and sociolinguistics. Your role will involve challenging advanced language models on various linguistic topics such as verb conjugation, noun-adjective agreement, subjunctive usage, sentence structure, regional dialects, word order, idiomatic expressions, and cultural subtleties—diligently documenting any discrepancies to strengthen model reasoning.On a daily basis, you will engage with the model on language scenarios, verify its factual accuracy and logical integrity, capture reproducible error patterns, and propose enhancements to our prompt engineering and evaluation metrics.A Master’s degree or PhD in Spanish language, linguistics, or a related field is preferred. Experience with peer-reviewed publications, teaching, or practical linguistic analysis projects will be advantageous. Exceptional communicative skills and the ability to articulate your thought process are essential.Are you ready to leverage your Spanish language expertise to create the knowledge base for the AI of tomorrow? Apply now and contribute to shaping the model that will educate the world!

About Us:At Wizeline, we are a premier global technology solutions provider specializing in AI-native digital products and platforms. Our mission is to empower organizations by harnessing data and AI to expedite their market presence and transform their operations. We pride ourselves on fostering an innovative culture that emphasizes growth, collaboration, and impact.With the right talent and innovative ideas, the possibilities are endless.Are You the Right Fit?If this sounds exciting, let’s see if you align with the following:

Yopeso brings nearly two decades of experience in software development, building both large-scale systems and tailored products. The company employs more than 300 professionals across five global locations, with a steady focus on growth, transparency, and professionalism throughout each project. Authenticity, curiosity, and ambition shape daily work at Yopeso. Teams operate with trust and integrity, maintaining open communication and a commitment to secure, reliable software. Each project emphasizes high quality and dependable performance. Collaboration plays a central role. Agile teams share knowledge and support one another, working efficiently to deliver software that aligns with the company’s core values and meets real-world needs.

About the Role Talan is looking for a Senior Full Stack Developer in Málaga. This position works across both front-end and back-end technologies to design and build applications that improve user experience and support business goals. What You Will Do Develop and maintain web applications from concept through deployment Collaborate with team members to deliver high-quality solutions Apply experience in both front-end and back-end development to solve complex problems Contribute to technical decisions and share knowledge with colleagues Location This role is based in Málaga.

About UsAt Leadtech, we have been at the forefront of digital innovation since 2009, crafting unique online solutions that engage millions of users each month. Our vibrant team of over 700 professionals hails from more than 23 nationalities, bound together by a shared enthusiasm for creativity and teamwork.We excel in delivering user-focused experiences across web and mobile platforms, allowing users to connect with our products like never before.We take pride in our global presence and are dedicated to nurturing an inclusive workplace where every team member contributes to our collective goal of realizing cutting-edge projects. Discover more about our journey and mission on our website!About the RoleWe are seeking a MarTech Full-Stack Developer to join our dynamic Marketing Technology & AdTech team.This role is not about merely centering buttons or debating design details for three sprints; instead, you will operate at the nexus of engineering, attribution, internal tooling, and growth. Your work will involve constructing the systems that enhance campaign measurement reliability, streamline data flows, and empower marketing teams to make informed decisions.You will be instrumental in maintaining and advancing the technical infrastructure for tracking, postbacks, schemas, integrations, and internal tools. This includes enhancing our internal CRM/tooling, optimizing marketing team operations, and ensuring data is transferred accurately, timely, and in the appropriate format.Your collaboration with performance marketers, product owners, developers, and data stakeholders will be crucial, as you bridge the gap between business requirements and technical execution.We value your skills and problem-solving abilities over formal education. Whether your background is in Computer Science, Physics, Philosophy, or whether you're self-taught, from a bootcamp, or have learned through experience, we welcome you. What matters to us is your capability, thought process, and sense of ownership.Additionally, if you leverage AI to enhance your productivity, clarity, or automate mundane tasks, that would be a significant advantage.What You’ll Be DoingAttribution & Tracking InfrastructureDesign and maintain attribution and tracking systems across web and app environments.Utilize tools such as GA4, Appsflyer, Adjust, and server-side/custom setups.Manage event deduplication, postback routing, conversion events, and parameter consistency.Establish, maintain, and enforce tracking schemas across projects.Ensure that tracking is not only implemented but is also reliable and usable.Internal Tooling & CRMDevelop and enhance features within our internal CRM and marketing tools.Create internal UIs and workflows that enable marketing teams to operate more independently.Optimize existing tools rather than reinventing them from scratch.Tackle real, complex operational challenges rather than just clean-cut tasks.