Backend Engineer (Go) at Prelude | Paris, France

About PreludeAt Prelude, we are pioneering a new standard for user onboarding and authentication in an era where trust, speed, and conversion are paramount.Our innovative solutions streamline user verification, enhancing security and efficiency while transforming authentication into a strategic advantage. Our flagship product boasts the highest price-to-conv…

Join us as a pivotal member of the Backend team at amo, where you'll play a critical role in shaping our infrastructure. In the initial months, you will collaborate closely with the team and gradually take charge of key components and features. At this early stage of our journey, we are in search of adaptable engineers who are eager to contribute across multiple facets of our company’s foundation.We appreciate team members who dive deeply into their areas of expertise, fostering a culture of subject matter mastery within our team. This dedication to specialization is a core expectation for every engineer.Our backend team is responsible for both server-side operations and the backbone of the client, as we believe a unified team can more effectively manage topics like networking, data modeling, management, and synchronization.As a Backend Engineer, your daily responsibilities will include:Building the FutureYou will develop robust systems designed to handle significant traffic, vast amounts of data, and an unparalleled rate of scaling. Your toolkit will include cutting-edge technologies, elegantly crafted code, and systems built for seamless horizontal scaling.Ensuring Cross-Platform CohesionBeyond server-side development, you will be involved in the enhancement and maintenance of a Rust component shared between iOS and Android. This component primarily focuses on networking, data synchronization, and data-oriented feature logic, benefiting from a single codebase. You will collaborate with mobile engineers to ensure a consistent experience across platforms and bridge the gap between mobile development and backend architecture for a cohesive user journey.Innovative Feature DevelopmentEngage in brainstorming sessions to design and implement unique features that distinguish us in the marketplace.Commitment to Continuous ImprovementWe value mutual learning and staying updated with industry trends and emerging technologies, encouraging fresh ideas and contributions to our culture of continuous improvement.Ownership of Your DomainYou will monitor analytics and manage system incidents, taking ownership of your responsibilities and proactively addressing issues and bug fixes.

About H H focuses on advancing superintelligence through agentic AI. The company’s mission centers on automating complex, multi-step tasks that people usually handle, aiming for AI agents to help realize the full range of human potential. H seeks talented AI professionals who care deeply about responsible and safe development, as well as technical progress in agentic systems. The culture values openness, ongoing learning, and teamwork. Every team member’s input matters here. Product Engineering at H The Product Engineering team develops H’s Enterprise Platform, which provides customers with tools and services for essential operational needs. This platform supports large-scale computer-use agents, manages complex workflows, and offers a suite for observability, troubleshooting, and evaluation. Product Engineering connects AI research with practical applications and works closely with teams across the company.

Are you ready to take your career to the next level? Join Adaptive ML as a Backend Engineer and be part of a cutting-edge team that is transforming the landscape of machine learning. In this role, you will design, develop, and maintain scalable backend solutions that drive our innovative applications.

Join Back Market as a Backend Engineer Apprentice and embark on a journey to innovate and enhance the circular economy through technology. As a part of our dynamic team, you will gain hands-on experience in backend development, contributing to our mission of creating a more sustainable world.

About VoodooFounded in 2013, Voodoo is a pioneering tech company dedicated to crafting innovative mobile games and applications aimed at entertaining users globally. With a vibrant team of 800 professionals, we have achieved an impressive 7 billion downloads and boast over 200 million active users, positioning Voodoo as the third largest mobile publisher worldwide in terms of downloads, trailing only Google and Meta. Our portfolio features hit games like Mob Control and Block Jam, alongside trending applications such as BeReal and Wizz.Our TeamAt BeReal, we prioritize authenticity in social media. By motivating our users to share unfiltered moments, we nurture genuine connections and embrace real-life experiences. Our international team has grown to over 60 members, serving more than 30 million monthly active users. Supported by Voodoo, we are committed to transforming BeReal into an iconic social network with hundreds of millions of users.Your RoleWe have developed BeReal with a compact team of elite engineers and intend to uphold this philosophy as we expand our user base to hundreds of millions. To realize this vision, we consistently release new features rapidly, outpacing other established social networks while enhancing our infrastructure. Our engineers work in agile, cross-functional teams, granting them significant autonomy in product-related decisions.Overcome thrilling technical challenges, particularly as our product handles spikes of millions of users connecting within a two-minute window.Play a key role in developing a robust architecture that can support massive scale as we attract new users and expand into new markets.Collaborate closely with product and engineering teams to innovate and implement new features for the app.Evaluate trade-offs and tackle technical challenges related to critical components of our backend systems.Engage in code and design reviews to uphold our high standards of quality.Our Technology StackInfrastructure: GCP, Kubernetes, Pub/Sub, GitHub Actions, ArgoCD.Backend: Go, Node.js (NestJS, Nx, Typescript)Frontend: Swift (iOS), Kotlin (Android).Database: Spanner, PostgreSQL, Redis.Candidate ProfileYou possess over 8 years of experience in developing APIs within distributed architectures.You have extensive experience in Go and have successfully contributed to the development of high-volume API microservices.You are self-reliant, proactive, and a strong team player with a passion for solving complex problems.You thrive in fast-paced environments and are eager to contribute to the growth of our innovative platform.

About UsAt Harmattan AI, we are pioneering the development of autonomous and scalable defense systems. With a recent $200 million Series B funding round that has raised our valuation to $1.4 billion, we are poised for growth and are seeking talented individuals to join our mission of delivering cutting-edge systems to allied forces.Our guiding principles are centered around creating impactful technologies, striving for excellence, setting ambitious objectives, and confronting complex technical challenges head-on. We thrive in a dynamic environment where accountability, precision, and execution are critical.About the RoleWe invite a passionate Backend Software Engineer to become a vital part of our C2 Core team in Paris. In this role, you will be instrumental in developing the foundational architecture for our advanced tactical Command and Control (C2) application. You will operate in a high-stakes, technical environment where low latency, high availability, and secure data management are crucial.Your primary responsibilities will involve ensuring seamless data flow for real-time telemetry, high-bandwidth video streams, and mission commands between our fleet of robots and the internal C2 components, including the Common Operational Picture (COP) and Mission Planner. This system is designed for deployment on ruggedized tactical PCs in field environments often characterized by limited network connectivity.

Join Arago and the AragoniansAt Arago, we are a pioneering AI and computer hardware firm dedicated to advancing history through technological innovation. Our mission is to propel breakthroughs at the intersection of artificial intelligence and semiconductor technology.Founded in 2024 by a team of accomplished AI researchers and physicists, Arago combines expertise in photonics, electronics, software, mathematics, and machine learning. Our lean, diverse team hails from top companies and renowned research institutions around the globe.With employees representing nine nationalities and operating from strategic locations in France, North America, and Israel, we are driven by our commitment to excellence and rapid progress. Our guiding principles include:Deliver excellence: We take pride in our work and its impact.Act with urgency: We prioritize speed and efficiency.Foster unity: We build relationships based on trust, respect, and teamwork.With strong backing from leaders at Apple, Arm, Nvidia, Microsoft, and Hugging Face, along with significant support from leading deeptech venture firms in the US and Europe, we are poised for remarkable growth.

Join us at iliad-free in Paris as a Staff Engineer specializing in Python. You will take on a pivotal role in our ambitious program aimed at modernizing and evolving our backend systems.Your primary responsibility will be to lead the technical direction of our information system backend, which manages all Free subscribers, including subscription processes, subscriber spaces, and additional services such as video streaming and mobile phone sales.In this role, you will develop a deep understanding of complex business processes executed by our system, such as billing for third-party services, subscription management, and fiber optic connections.You will guide the team in defining the architecture of this distributed system while actively contributing to development using Python, ensuring hands-on involvement.Your expertise will drive development practices that prioritize resilience, quality, testability, and speed of delivery. Additionally, you will be instrumental in establishing robust operational methods in a model where development teams manage their solutions in production, with a constant focus on performance and scalability.

Overview: We are seeking a talented Product Engineer specializing in Backend Development with Rust to take charge of and enhance the foundational systems that ensure AI safety at a large scale. Your role will involve constructing APIs capable of managing hundreds of millions of requests, implementing real-time policy enforcement, and developing high-throughput data pipelines.About UsWhite Circle is at the forefront of AI Safety, creating the essential safety, reliability, and optimization framework for AI systems. Our platform is built on policies—easily understandable natural-language rules that outline appropriate AI model behavior. We automatically test, enforce, and continuously refine these policies on a massive scale.We have secured $11M in funding from leading investors, founders, and executives from OpenAI, Anthropic, HuggingFace, Mistral, DeepMind, Datadog, Sentry, and others.Our systems process over one hundred million API calls each month.We optimize and train our own LLMs to operate more swiftly and cost-effectively than any publicly available or proprietary models.As a compact and highly focused team, we welcome those eager to tackle challenging problems, deliver their work to production swiftly, and actively shape the future of AI safety.Your Responsibilities:Design and implement backend services in Rust that facilitate real-time policy evaluations at scale, ensuring low latency and high reliability.Take ownership of features from inception to deployment: API design, database schema development, and continuous monitoring and iteration.Engage with different layers of the stack as needed; we prioritize problem-solving over rigid role definitions.Enhance system performance and reliability through connection pooling, caching strategies, query optimization, and observability practices.Collaborate directly with product managers, researchers, and ML teams to convert requirements into effective production systems.Ideal Candidate:You have experience building and deploying backend systems in Rust—beyond mere tutorials, you have real-world production experience.You are well-versed in async Rust (Tokio), web frameworks (Axum, Actix), and database interaction patterns.You possess strong system design fundamentals, capable of assessing trade-offs, failure modes, and scalability.You have hands-on experience with PostgreSQL, adept at crafting efficient queries and designing schemas.

About the Role airapps is looking for a backend engineer to help build and maintain the systems behind our applications. This position is based in Paris and focuses on developing backend solutions that scale and perform reliably. What You Will Do Design, implement, and maintain backend systems for airapps products Work closely with teammates to solve technical challenges Contribute to a collaborative team environment Who We’re Looking For Experience building backend systems Comfort working with others to solve problems Interest in developing efficient and scalable solutions This is a full-time role in Paris. If building reliable backend infrastructure with a team sounds appealing, airapps would like to connect.

Join our dynamic team at myjobcompany1 as a Backend PHP Developer! We are on the lookout for a talented individual who is passionate about coding and eager to work on innovative projects. In this role, you will be responsible for developing and maintaining backend services, ensuring high performance and responsiveness to requests from the front-end.As part of our team, you will collaborate with front-end developers to integrate user-facing elements using server-side logic, and you will contribute to all phases of the software development lifecycle. We value creativity and technical expertise, and we encourage our team members to suggest improvements and new technologies.

About UsHarmattan AI is a pioneering defense technology firm dedicated to creating autonomous and scalable defense systems. Following a successful $200 million Series B funding round, which values the company at $1.4 billion, we are actively expanding our team to develop and deliver essential systems for allied forces.Our mission is driven by core values: crafting impactful technologies, striving for excellence, setting ambitious goals, and tackling complex technical challenges. We thrive in a high-pressure environment where accountability and execution are paramount.About the RoleWe are seeking a dynamic Head of Engagement to spearhead our global Engagement function.In this role, you will oversee and expand a team of Engagement Managers across Europe, the Middle East, the US, and future markets, shaping how Harmattan AI interacts with its customers—from technical demonstrations to comprehensive deployment and enduring partnerships.This position sits at the crossroads of Sales, Product, and Field Operations, playing a critical role in our success in securing tenders, executing deployments, and fostering a robust partner ecosystem.

Main ResponsibilitiesDesign, develop, and maintain backend applications using Java (Spring Boot).Define, implement, and optimize event flows on Apache Kafka (topics, partitions, performance, security).Participate in software architecture decisions and the industrialization of real-time solutions.Ensure code quality through unit tests, continuous integration, and code reviews.Contribute to the deployment and monitoring of applications (CI/CD, monitoring, support).Collaborate closely with Product, Data, and Infrastructure teams.Provide insightful suggestions for improving technical and methodological best practices.

Join our dynamic team at Iliad as a Backend Python Developer in Paris! We are looking for passionate and skilled individuals to contribute to our innovative tech projects. You will work closely with cross-functional teams to design and implement robust backend systems, ensuring high performance and responsiveness to requests from the front-end.Key Responsibilities:Develop and maintain server-side applications using Python.Collaborate with front-end developers to integrate user-facing elements.Optimize applications for maximum speed and scalability.Participate in code reviews and contribute to team knowledge sharing.Stay updated with emerging technologies and best practices.

Are you passionate about improving user experiences and ensuring seamless onboarding processes? Join Algolia as a Technical Onboarding & Engagement Manager. In this dynamic role, you will facilitate the onboarding of our clients, ensuring they maximize the value of our powerful search and discovery solutions.Your primary responsibility will be to guide clients through the implementation of our technology, providing expert advice and support to enhance their engagement. You will play a crucial role in fostering long-term relationships and ensuring customer satisfaction.

About UsAt Harmattan AI, we are pioneering the development of autonomous and scalable defense systems. With the successful completion of our $200M Series B funding round, valuing our company at $1.4 billion, we are on a mission to expand our team and enhance our capabilities to provide mission-critical solutions to allied forces.We are driven by our core values: creating technologies that make a tangible impact, striving for excellence, setting ambitious goals, and tackling the most challenging technical problems. Our work culture emphasizes rigor, ownership, and effective execution in a fast-paced environment.About the RoleWe are seeking an Engagement Manager to spearhead technical customer engagement, demonstrations, and partner integrations throughout the EU region. This pivotal role bridges Sales, Product, and Field Operations, playing a crucial part in transforming strategic opportunities into deployed systems and enduring partnerships.ResponsibilitiesLead and execute technical demonstrations that align with ongoing tenders and customer specifications.Serve as the primary technical liaison for customers, partners, and OEMs.Convert operational requirements into comprehensive system solutions, including mission profiles, architectures, and workflows.Facilitate OEM integrations with prime contractors, manufacturers, and strategic partners.Assist Sales in high-stakes deals and tender submissions.Act as a point of escalation for complex technical challenges and deployments.Enhance and standardize demonstration workflows, tools, and demo kits to ensure quality and consistency.Conduct competitive benchmarking and provide structured market insights.Gather and communicate field feedback and customer insights to Product and Engineering, shaping roadmap decisions.Oversee the preparation and execution of field deployments, logistics, and system delivery.Collaborate effectively across Sales, Product, Engineering, and Logistics teams.

We are looking for a dynamic and passionate Local Growth & Community Engagement Lead to join our team at Lightspeed Commerce. In this pivotal role, you will be responsible for driving community initiatives and fostering local growth strategies that resonate with our diverse customer base. Your ability to connect with local businesses and engage with community stakeholders will be essential in building strong relationships and promoting our brand.

Role Overview Accor S.A. is hiring a Senior Java Backend Developer for its Paris office. This position focuses on building and maintaining backend systems that support hospitality services worldwide. What You Will Do Design, implement, and maintain backend solutions using Java. Work closely with team members to deliver systems that improve both internal operations and guest experiences. Contribute technical expertise to projects that drive service quality and efficiency. Impact Your work will shape the reliability and performance of core systems at Accor, directly supporting the way guests experience our services.

Join Sobi as the Global Omnichannel Customer Engagement Lead, a pivotal role where you will drive customer engagement strategies across multiple channels. You will be responsible for enhancing customer experiences and ensuring consistent messaging that aligns with our global brand vision. Collaborate with cross-functional teams to implement innovative solutions that meet the needs of our customers worldwide.