Senior Backend Engineer at Aircall | 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!

Groupon is a dynamic marketplace that connects customers with exciting experiences and services, empowering local businesses to thrive. Having partnered with over a million merchants worldwide, we facilitate connections for 16 million customers seeking deals across diverse categories. In a world dominated by e-commerce giants, we pride ourselves on being a platform genuinely committed to the success of local businesses through performance-driven strategies.At Groupon, we are on an ambitious journey to transform our operations with a relentless focus on achieving results. Despite our global presence with thousands of employees, we uphold a culture that fosters innovation, encourages risk-taking, and celebrates success. Here, your impact can be immediate, as we operate on a scale that allows for rapid transformation. We embody a "best of both worlds" philosophy—large enough to offer robust resources, yet small enough for individuals to wield significant autonomy and make a meaningful impact.About the RoleJoin our CoreApps Platform team, the backbone of Groupon's engineering efforts responsible for the global commerce engine. Our platform manages every customer interaction and transaction on a worldwide scale. In this high-impact, senior-level Individual Contributor (IC) role, you will focus on ensuring KTLO stability at massive scale while advancing a significant platform modernization initiative through an AI-first approach.You will take ownership of mission-critical services that handle over 100,000 Requests Per Minute (RPM) and drive the transition from legacy Java/Ruby systems to a modern TypeScript/Node.js microservices architecture, utilizing cutting-edge AI coding tools to achieve unmatched speed and quality.

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

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

Ebury empowers ambitious businesses to achieve global growth, and we apply this same philosophy to our team members. We promote innovation, collaboration, and problem-solving while creating an inclusive environment where everyone feels valued and supported to succeed.If you’re a team player eager to revolutionize the way businesses function on a global scale, we invite you to connect with us. Ebury is excited to help accelerate your career and enable you to shape the future.Senior Data Platform EngineerMadrid Office - Hybrid: 4 days in the office, 1 day working from homeBecome a key part of our Data Team at Ebury's Madrid Office.Our ambitious growth strategy hinges on the success of our Data team, and we are looking for a Senior Data Engineer to join our Data Platform team! Our goal is to develop, maintain, and enhance Ebury’s Data Platform focusing on scalable, robust, and innovative frameworks.In your role as a Senior Data Platform Engineer, you will collaborate with your team to develop and improve our Data Platform.

Managing corporate spending can often be a challenging endeavor, with convoluted processes that hinder efficiency for finance teams and employees. At Pleo, we are revolutionizing this process. We provide financial solutions designed to simplify money management, making it seamless and remarkably efficient for everyone involved. Our mission is to empower businesses to 'go beyond' traditional spending methods.The name 'Pleo' translates to 'more than you’d expect', and this philosophy has underpinned our success over the last decade.We find ourselves at a crucial juncture in our growth; every decision we make impacts over 40,000 customers and is vital to our mutual success. We seek individuals who are committed to understanding customer needs, transforming complex challenges into straightforward solutions, and questioning the status quo—all while aiming high. With ambitious goals propelling us forward, we embrace the journey of discovery and innovation. Our team consists of over 850 talented individuals representing more than 100 nationalities, all dedicated to shaping the future of business spending.About the RoleWe are in search of a Senior Backend Engineer to join our dynamic team at Pleo. In this role, you will play a key part in developing and scaling our backend systems while engaging in exciting projects as we enhance our product and service offerings. If you are passionate about tackling complex technical challenges and thrive in a culture that prioritizes transparency, collaboration, and innovation, this position is made for you.Your ResponsibilitiesAs a Senior Backend Engineer, you will:Lead the design, development, and maintenance of scalable microservices primarily using Kotlin.Collaborate with cross-functional teams to create innovative solutions across various domains including Platform and Services.Analyze system performance and implement optimizations to ensure high reliability and scalability.Participate in code reviews, conduct post-mortems, and mentor fellow engineers.Proactively address technical debt and guide the team through technical challenges and migrations.QualificationsYou will excel in this role if you possess:Strong expertise in server-side programming, particularly in Kotlin, and experience with distributed systems, microservices, and various cloud environments such as AWS and Kubernetes.Proficiency in relational databases such as PostgreSQL, testing frameworks (e.g., JUnit, Testcontainers), and observability tools like Grafana.

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.

Ebury empowers ambitious businesses to achieve global expansion, mirroring this ethos in our approach to our team. We champion innovation, collaboration, and problem-solving, creating an inclusive environment where everyone feels valued, supported, and empowered to thrive.If you're a collaborative professional eager to revolutionize global business operations, connect with us. We would be delighted to discuss how Ebury can accelerate your career trajectory and enable you to influence the future.Join Our Data Team as a Senior Data Engineer - AI PlatformHybrid Work Model: 4 days in the office, 1 day remoteBecome a part of Ebury's Data Team in our Madrid or Málaga office.The success of Ebury's strategic growth plan heavily relies on our Data team, and we are on the lookout for a skilled Data Engineer - AI Platform to enhance our Data Platform Engineering team!Our mission centers on developing, maintaining, and enhancing Ebury's Data Platform, with a current focus on constructing the Agentic Data Plane (ADP): a cohesive, governed interface layer for AI and agentic products that simplifies data communication and access while ensuring governance, lineage, traceability, and full replayability.As an AI Platform Engineer, you will collaborate closely with the Data Platform team and cross-functional domain teams to design and deliver the platform capabilities that allow Ebury to safely deploy AI and agentic products at scale.What We Offer:Attractive salary and benefits packagePerformance-based discretionary bonusOngoing personal development through training and certificationSupportive of Open Source principles, encouraging contributions to both internal and external projects

Ebury is hiring a Senior Data Engineer - AI Platform to join the Data Platform Engineering team in Madrid or Malaga. This hybrid position requires working onsite four days each week, with one day remote. Team focus The Data team supports Ebury’s growth by building, maintaining, and improving the company’s Data Platform. The group works closely with business operations and leads projects that enable new AI initiatives. Key responsibilities Collaborate with the Data Platform team and other domain teams to design and implement new platform features. Develop the Agentic Data Plane (ADP), which serves as a unified, governed interface layer for AI and agentic products. Ensure the platform enables secure and scalable deployment of AI and agentic solutions. Contribute to systems that improve data access, governance, lineage, traceability, and replayability. Work arrangement Role based in Madrid or Malaga. Hybrid schedule: four days onsite, one day remote per week.

Blacklane is seeking a Platform Engineering Manager to join the team in either Barcelona or Madrid. The focus of this role is to turn the internal platform into a unified product that connects infrastructure with developer needs. The manager will lead a growing team, aiming to streamline the developer experience and help product teams deliver more effectively. Key Responsibilities Define the direction and structure of the platform in partnership with a Staff Engineer, shaping both the team and the roadmap. Establish and maintain standards for engineering quality, prioritizing strong outcomes over simply closing tickets. Oversee delivery schedules and project scope, making decisions that influence business results. Clarify ambiguous requirements and translate them into clear, actionable plans, balancing progress with thoughtful trade-offs. Coach and support the Platform team, fostering growth, performance, and collaboration. Communicate openly with other Engineering Managers to coordinate expectations and manage dependencies. Requirements Background in Platform, Backend, or Data Engineering, with experience building and leading effective teams. Proactive in identifying and addressing challenges, able to develop business cases, gain support, and follow through on plans. Skilled at managing complex, cross-team projects and delivering strong results. Dedicated to continuous learning and consistently completes work to a high standard. Location This role is based in Barcelona or Madrid.

Join Nexthink as a Platform Engineer, where you'll play a pivotal role in enhancing the Engineering Productivity team's initiatives to empower product engineering teams in delivering exceptional software efficiently and at scale.In this dynamic position, you will take ownership of our enablement platform and productivity tools, focusing on the evolution and automation of our CI/CD stack. Your efforts will drive significant enhancements in delivery workflows, system reliability, and the overall software development lifecycle by minimizing friction and maximizing effectiveness.As the landscape of software development transforms with the integration of AI-assisted workflows and autonomous practices, your expertise will be crucial in guiding our platform's evolution to meet these new demands.Your contributions will help modernize our delivery platform to include:AI-augmented and agentic development methodologiesAutomation-first engineering principlesRobust, self-service CI/CD capabilities designed for scalabilityEmbrace the challenge to elevate engineering productivity across the organization while preparing our platform for the future of software development.

The Senior Platform Architect within the Customer Outcomes team plays a vital advisory role, focusing on assisting our clients in establishing a robust technical foundation on the ServiceNow Platform and crafting solutions that yield significant outcomes. This position ensures that clients adhere to best practices in instance strategy, technical governance, core data management, integrations, and overall platform health. As a consultative expert, you will guide ServiceNow, partner, and customer teams towards architecture solutions designed for sustained success.Engage with clients across various levels, including executives, platform owners, enterprise architects, and development teams, throughout the selling, structuring, and implementation phases.Serve as an architectural advisor across multiple engagements, facilitating successful solutions for customers, partners, and internal teams.Provide extensive architectural insights across diverse workflows.Build strong relationships with CoEI and business leaders at customer locations to comprehend the role of ServiceNow in their digital transformation journeys.Convert strategic goals into actionable customer roadmaps.Translate business and technical requirements into comprehensive architectural blueprints to meet complex objectives.Collaborate with clients' Enterprise Architects to position ServiceNow as the standard for digital transformation, ensuring integration with core applications.Oversee technical governance and the operational delivery model.Work with engagement teams to improve instance health by minimizing technical debt and aligning with ServiceNow's leading practices.Contribute actively to the sales process by scoping and estimating engagement and change orders.Share your expertise and promote leading practices related to the ServiceNow platform.

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!

Role overview Ebury is hiring an AI Platform Engineer for the Data Platform Engineering team based in Madrid (or Malaga). This hybrid position requires four days per week onsite and one day remote. The team is central to Ebury’s growth, focusing on building and maintaining the infrastructure that powers AI and agentic products throughout the company. What you will do Develop and maintain the Ebury Data Platform as part of the Data Platform Engineering team. Help build the Agentic Data Plane (ADP), which serves as a unified and governed interface for AI and agentic products. Design and implement features to simplify data communication and access, while maintaining governance, lineage, traceability, and replayability. Work closely with cross-functional domain teams to support secure and efficient deployment of AI and agentic products at scale. Work environment Hybrid schedule: four days onsite in Madrid (or Malaga), one day remote. Team values innovation, collaboration, and strong problem-solving skills. Supportive culture where team members are encouraged to grow and contribute to Ebury’s mission.

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.

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.

Location: Madrid (Hybrid: 4 days in office, 1 day remote) Role Overview Ebury is seeking an experienced Engineering Manager to lead the Platform Foundations AWS team. This role involves direct management of engineering teams, technical oversight, and setting the technical direction for the core infrastructure layer, with a primary focus on AWS. The position is based in Madrid and follows a hybrid work model. The Platform Engineering Manager will ensure the resilience, compliance, scalability, and cost-effectiveness of Ebury's foundational AWS platform. Areas of responsibility include Cloud Infrastructure, Networking, Observability, and key CI/CD capabilities. Experience working in highly regulated environments is essential, as this role manages relationships with internal and external audit bodies relevant to platform operations. This position also supports Ebury’s global expansion, including integrating infrastructure for new subsidiaries and M&A activities. What You Will Do Technical Leadership and Execution Shape and guide the technical roadmap for the team, covering AWS infrastructure, networking, and foundational tooling over a 6-12 month horizon. Direct strategic approaches for AWS cloud operations and infrastructure automation, focusing on security, consistency, and cost efficiency. Take responsibility for the reliability, availability, security, and scalability of core infrastructure components. Lead technical implementation for global platform integration within AWS, supporting new subsidiaries and M&A activities through standardized infrastructure provisioning and best practices. Serve as a technical mentor and authority, advising engineers on complex architecture decisions and best practices. Delivery Management and Operations Oversee...

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).