Senior Backend Engineer at Pleo | Madrid, London, Lisbon

neoris is looking for a Backend Software Engineer with a focus on .NET technologies to join the team in Madrid, Spain. This hybrid position involves both in-office and remote work. Role overview This role centers on designing, developing, and maintaining backend systems that support neoris applications. The work involves building reliable services and ensuring performance and scalability. Collaboration Work closely with colleagues from different disciplines to deliver software solutions that align with business objectives. Regular communication with cross-functional teams is part of the job. Location This is a hybrid role based in Madrid, Spain. Some days will be spent in the office, with flexibility for remote work.

Join our innovative team as a Junior Software Engineer focused on backend development in .NET. You will play a crucial role in ensuring the quality, development, and execution of our software products.As part of our dynamic technology department, you'll collaborate with a diverse group of professionals from cities like Barcelona, New York, London, Manchester, Bucharest, and India. If you're eager to make an immediate impact in a growing company, we are excited to hear from you!About TransPerfect – TechOps:The TransPerfect TechOps team has been instrumental in our success for over a decade, delivering cutting-edge technology and services that enhance the workflow for our clients and colleagues. From optimizing our GlobalLink platform to creating user-friendly client interfaces, your contributions will help simplify complex systems for novice users.

Join our dynamic global team as a Software Engineer, where you will play a crucial role in ensuring the quality, development, and implementation of our innovative software products. As part of a diverse technology department, you will collaborate with talented professionals from cities like Barcelona, New York, London, Manchester, Bucharest, and India. If you're eager to contribute to a growing company and make a significant impact, we would love to hear from you!About TransPerfect – TechOps:The TransPerfect TechOps team has been instrumental in our company's success for over a decade, delivering technology and services that have greatly enhanced the experiences of our clients and colleagues. From improving workflows for team members to developing core services that underpin our GlobalLink platform, we strive to create scalable client interfaces that make complex ecosystems accessible to everyone.

Location: Madrid Office About Aircall Aircall builds an AI-driven customer communications platform used by over 22,000 businesses worldwide. Our product brings together voice, SMS, WhatsApp, and AI features in a single workspace, helping teams boost revenue, resolve issues faster, and scale their operations efficiently. Headquartered in Paris, Aircall has a strong global footprint with offices in Seattle, Madrid, London, Berlin, San Francisco, New York City, Sydney, and Mexico City. Our company is growing quickly, supported by leading investors and advances in AI across our product lines. Our Culture We focus on customer satisfaction, data-driven decisions, and meaningful results. Team members are encouraged to take ownership, keep learning, and act quickly but thoughtfully. Collaboration, trust, and impact shape our daily work. About the New Product Unit Aircall is launching a New Product Unit dedicated to advancing autonomous sales. The team is building an AI Orchestration Layer that records and understands customer interactions across calls, video, email, and WhatsApp. This system will automate sales workflows such as CRM updates, follow-ups, task creation, and coaching insights. Our long-term vision is a self-optimizing Sales OS powered by specialized AI agents working together to improve revenue processes. Role Overview: Senior Backend Software Engineer (Python) This position calls for an experienced backend engineer with strong Python skills, ready to work beyond traditional backend boundaries. The role suits someone who values both clean architecture and practical progress, and who can balance high-quality work with the need for speed in a startup setting. What You Will Do Tackle complex technical challenges, including distributed systems, AI orchestration, architecture, performance, and scalability Contribute to the design and implementation of backend systems for the AI Orchestration Layer Work closely with product and engineering teams to deliver new features Iterate quickly, shipping solutions and learning from feedback Who Will Thrive Engineers who enjoy solving difficult problems and making architectural decisions Those who can dive deep into technical details while keeping an eye on rapid delivery People who take pride in their work and appreciate the pace of a growing company

At Datadog, we are revolutionizing how engineers monitor, secure, and scale their infrastructure and applications, driving reliability and performance for thousands of businesses. We process trillions of data points daily and address challenges related to scale, speed, and resilience. We are in search of seasoned backend engineers eager to take charge of vital services and enhance their expertise in distributed systems. If you have experience in building APIs, data pipelines, or backend tools, this position offers an opportunity to expand your influence while mastering the design and operation of high-scale, high-availability systems that underpin observability and security solutions utilized by engineers globally. At Datadog, we cherish our office culture—the relationships it fosters, the creativity it encourages, and the teamwork it cultivates. We embrace a hybrid work model, empowering our employees to achieve a work-life balance that suits them best.

Are you ready to make a significant impact? At Cabify, we are on a mission to transform urban living by enhancing mobility for residents, seamlessly connecting riders with drivers at their fingertips. Our vision is to create cities where private cars are a thing of the past. Are you interested in being part of this transformative journey? At Cabify, our commitment to diversity shapes our Product & Engineering teams. We actively seek talent from a variety of backgrounds, supporting initiatives such as Women Tech Dating and our Internal Diversity Committee. Our inclusive job descriptions reflect our dedication to an environment where every contribution is valued. Join us to be a part of innovative teams that truly mirror the diverse talent in the tech sector. With over 20 million users globally, we operate in 8 countries and 90 cities, rapidly adapting our product to maintain leadership in various markets while prioritizing sustainability. The Role: We are seeking a skilled Backend Software Engineer with experience in any backend technology. Your day-to-day tasks will involve working with Go, Elixir, or Ruby. Even if your background is primarily in languages like Java, we believe you can quickly adapt and learn new languages. What matters most to us is your adaptability and ability to learn programming languages swiftly. At Cabify, you will: Collaborate with principal engineers on development planning and architectural design. Coordinate subprojects, building and maintaining robust, testable, and data-driven applications. Enhance the reliability, scalability, and performance of our services. Take ownership of your code all the way to production utilizing a self-service continuous delivery pipeline. Engage in host-level problem-solving and contribute to improving detection methods. Be a key player in fostering our engineering culture, prioritizing quality through peer reviews, monitoring, and best practices.

Join inetum2 as a Software Developer specializing in .NET technologies. This is an exciting opportunity for individuals looking to kickstart their careers in software development. You will work in a dynamic environment, collaborating with experienced professionals to build innovative software solutions.

Role Overview airapps is hiring a Backend QA Engineer based in Madrid. This position focuses on quality assurance for backend systems, helping to keep applications reliable and up to standard. What You Will Do Support QA processes for backend applications Work closely with team members to identify and resolve issues Help ensure applications perform as intended and meet quality expectations Who We’re Looking For Detail-oriented approach to testing and problem-solving Comfortable working within a collaborative team Motivated to deliver solid, dependable software Location This role is based in Madrid.

fiskaly develops technology that secures digital receipts and ensures legally compliant transactions for millions of users each day. By applying digital signatures, the company helps prevent tax fraud and supports merchants with a streamlined, paperless solution. The team is dedicated to simplifying receipts for everyone. Role overview This Senior Backend Engineer (Golang) position is a full-time, permanent role open to candidates based in or near Vienna, or within a two-hour time zone difference. The company is not considering freelancers for this role. What you will do Serve as a System Architect within a focused squad, developing API-first SaaS products. Lead backend development using Golang and other object-oriented languages, contributing throughout the software lifecycle. Apply modern tools, including AI coding assistants and automation, to minimize repetitive tasks and tackle complex problems. Design, build, and maintain distributed systems for fiskaly's fiscalization platform. Shape the architecture and scalability of the unified digital receipts interface. Requirements Minimum 5 years of backend development experience, with a strong background in Golang and object-oriented programming. Fluency in both German and English. Located in or near Vienna, or within a two-hour time zone difference. Available for full-time employment (no freelance contracts). Salary and contract Gross annual salary: €45,000 – €70,000 Full-time, permanent position

Managing expenses shouldn’t be a headache. At Pleo, we’re revolutionizing the way businesses handle spend management by creating solutions that simplify financial processes for both finance teams and employees. Our goal is to empower organizations to 'go beyond' traditional methods.Since our inception 10 years ago, we’ve embraced the philosophy of ‘Pleo’, meaning ‘more than you’d expect’, which has been pivotal to our success.We are currently at a significant juncture in our growth journey; every decision we make affects our more than 40,000 customers, our business, and our collective achievements. We are looking for individuals who take pride in identifying customer needs, transforming complex challenges into straightforward solutions, and respectfully challenging the status quo. With our ambitious goals ahead, we are a dynamic and diverse team of over 850 individuals from more than 100 nationalities, dedicated to shaping the future of business spending.About the RoleWe are seeking a skilled Backend Engineer to join our innovative team at Pleo. In this position, you will play a crucial role in building and scaling our backend systems, engaging in exciting projects as we expand our product and service offerings. If you are passionate about solving intricate technical challenges and thrive in a culture that values transparency, collaboration, and innovation, we invite you to apply.What You’ll Be DoingAs a Backend Engineer, your responsibilities will include:Designing, building, and maintaining scalable microservices primarily using Kotlin.Collaborating with cross-functional teams to develop innovative solutions across various domains such as Platform, Services, and SMB.Analyzing system performance and implementing optimizations to ensure high reliability and scalability.Participating in code reviews and post-mortems while mentoring fellow engineers.Proactively addressing technical debt and guiding the team through challenges and migrations.What You BringThis role is ideal for you if you possess:Experience in server-side languages, particularly Kotlin, along with expertise in distributed systems, microservices, and cloud environments (e.g., AWS, Kubernetes).Proficiency with relational databases such as PostgreSQL and familiarity with testing frameworks (e.g., JUnit, Testcontainers).

About the Role airapps is looking for a Backend Engineer in Madrid to help shape the systems behind our platforms. This role centers on building and improving backend architecture that supports our applications. What You Will Do Design, implement, and maintain scalable backend systems Work closely with teams across the company to deliver new features and solutions Contribute to the ongoing improvement of our backend platforms Location This position is based in Madrid.

As a Senior Backend/Platform Engineer at causaprima, you will be responsible for the foundational platform utilized by our agents. Your expertise will enhance our event-driven architecture, streamline data pipelines, integrate with customer accounting systems, and ensure that our infrastructure is reliable, auditable, and efficient.Key ResponsibilitiesEvent Store Management — Design and maintain an append-only PostgreSQL database featuring tamper-evident hash chaining, real-time event distribution, agent replay, recovery capabilities, and schema versioning.Cryptographic Signature Infrastructure — Establish key management and signature verification systems for all agent events while implementing approval chains for external actions.Workflow Constraint Engine — Develop a gateway to verify authorization for any external actions including emails, payments, or API calls.PII Vault & GDPR Compliance — Create isolated, encrypted storage solutions for personal data, ensuring compliance with the right to erasure and data residency requirements.Multi-Tenancy Management — Implement row-level security and tenant isolation across all data stores, including tenant-scoped LLM API keys.Authorization Framework (Cerbos) — Utilize attribute-based access control for both agents and humans, ensuring deterministic policy evaluation where LLMs do not make authorization decisions.MCP Security Layer — Develop authentication, capability-based scoping per partner, and rate limiting for the Model Context Protocol endpoint.Database Architecture — Focus on PostgreSQL schema design, indexing strategies, performance tuning, and read replica topology.

Join Aircall as a Senior Backend/Platform Engineer, where you will play a crucial role in enhancing our platform's infrastructure and backend systems. You will collaborate with cross-functional teams to design and implement scalable solutions that ensure seamless communication for our users. If you are passionate about crafting high-performance systems and thrive in a dynamic environment, we would love to hear from you!

Join Altersolutions as a DevOps Engineer and elevate your career in a vibrant hybrid work environment in Madrid. You'll be part of a dynamic team that is dedicated to leveraging cutting-edge technology and innovative practices to streamline operations and enhance productivity.

Are you passionate about leveraging AI technologies to enhance backend systems? Join docplanner as a Backend Engineer specializing in AI Integration. In this role, you will collaborate with a dynamic team to design, develop, and implement innovative solutions that integrate AI capabilities into our existing systems.Your expertise will contribute to optimizing processes and improving user experiences across our platforms. If you're ready to take your backend engineering skills to the next level while working with cutting-edge technology, we want to hear from you!

airapps is looking for a Backend DevOps Engineer based in Madrid. This position focuses on improving development workflows and supporting reliable application deployments. Role overview The Backend DevOps Engineer will work with both development and operations teams. The main goal is to make development processes smoother and ensure that applications are deployed efficiently. What you will do Collaborate with team members to implement continuous integration and continuous deployment (CI/CD) pipelines Manage and maintain cloud infrastructure Work to improve system performance and reliability Location This role is based in Madrid.

JetBrains is hiring a Product Designer to focus on the .NET ecosystem. This position involves designing developer tools that improve workflow and make daily tasks more enjoyable. The role is open to candidates in Belgrade, Berlin, Limassol, Madrid, Munich, Prague, Warsaw, Yerevan, or remote within Germany. What you will do Collaborate with engineers, product managers, and fellow designers to build user-centered solutions for .NET products. Shape the visual and interactive aspects of developer tools, ensuring usability aligns with technical needs. Turn research findings and user feedback into clear, effective design concepts. About JetBrains JetBrains creates intelligent software tools used by millions of developers worldwide. The team emphasizes thoughtful design and practical problem-solving to support the work of software professionals.

Join our dynamic team at Sopra Steria as a Python Developer in a hybrid work environment in Madrid. We are searching for a passionate individual who is ready to take on challenging projects and contribute to innovative solutions. Your expertise in Python will play a crucial role in developing and maintaining high-quality software that meets our clients’ needs.

Join our innovative team at Inetum as a Revit API .NET Developer (Dynamo). We are seeking a passionate developer who is proficient in .NET programming and has experience with the Revit API, specifically utilizing Dynamo for automating workflows and enhancing design processes. This is an exciting opportunity to work on cutting-edge projects in the architectural and engineering sectors.