Staff Software Developer (Kotlin Libraries)

At JetBrains, we are driven by a passion for code. Since our inception in 2000, we've dedicated ourselves to crafting the most powerful and efficient developer tools available. As AI-driven coding agents become integral to Kotlin development, we are committed to ensuring these tools excel in their purpose. The Kotlin AI Value Stream team plays a pivotal role in how AI agents comprehend, generate, and enhance Kotlin code across diverse platforms, including Android, Kotlin Multiplatform, server-side, web, and desktop applications. We develop evaluation infrastructures, error analysis tools, and post-training pipelines that assess and enhance agent performance on actual Kotlin developer tasks. In your role as a Research Engineer with our team, you will take charge of the complete feedback loop: Analyze failures in Kotlin code generated by agents, devise evaluations to identify those failures, research and implement strategies for improvement, and measure the outcomes. Your contributions will significantly influence how millions of developers interact with Kotlin through AI coding agents.

Join Celonis, a global leader in process mining and execution management, as a Manager of Value Engineering. In this role, you will spearhead initiatives that enhance our clients' operational efficiencies through innovative solutions and collaborative strategies. Your leadership will be key in driving value-based conversations with stakeholders, ensuring that the implementation of our software solutions delivers remarkable results.

Why Join Nebius?Nebius is at the forefront of revolutionizing cloud computing to empower the global AI economy. We develop cutting-edge tools and resources that enable our clients to tackle real-world challenges and revolutionize industries, all while minimizing infrastructure costs and reducing the necessity for large in-house AI/ML teams. Our workforce operates at the forefront of AI cloud infrastructure, collaborating with some of the most experienced and innovative leaders and engineers in the industry.Our Work EnvironmentBased in Amsterdam and publicly listed on Nasdaq, Nebius boasts a global presence with R&D centers across Europe, North America, and Israel. Our diverse team of over 1400 professionals includes more than 400 highly skilled engineers excelling in both hardware and software development, complemented by an in-house AI R&D team.The RoleThis opportunity is part of Nebius AI R&D, a team dedicated to applied research in AI. Recent applied research published by our team includes:Applying reinforcement learning for agent training in long-context multi-turn scenariosDramatically scaling task data collection to enhance reinforcement learning for software engineering (SWE) agentsDeveloping a decontaminated evaluation system for SWE agents that is consistently updatedInvestigating test-time guided search methods to create more powerful agentsThe outcomes of our research frequently pave the way for collaboration with adjacent teams, allowing practical applications of our findings.We are currently seeking experienced ML engineers at the senior and staff levels to engage in research projects that include:Guided search and reinforcement learning for agentic systemsReinforcement learning applications for reasoning modelsWeb-scale data collection for agent trainingEfficient model distillation techniquesKey Responsibilities:Conducting experiments to identify effective methods for training large language models based on interaction traces with various environmentsExploring guided generation and search methodologies within trajectory spacesDevising innovative strategies for mining relevant data at web scale

JetBrains has developed tools for software teams since 2000. By automating routine checks and corrections, JetBrains products help developers focus on building and shipping software. The goal: make development more productive and creative. Role overview This Backend Customer Success Engineer role centers on supporting engineering teams as they adopt Kotlin for backend development. The position focuses on helping organizations successfully bring Kotlin into production environments. What you will do Guide organizations through the process of moving from Java to Kotlin, assisting with migration, integration, and scaling. Troubleshoot technical challenges that arise during the transition and support teams as they progress from initial experimentation to stable production use. Work with potential users to clarify how Kotlin adoption works and help design migration plans that fit their specific needs. Locations Amsterdam, Netherlands Berlin, Germany Munich, Germany Prague, Czech Republic Remote, Germany

JetBrains s.r.o. creates tools that help developers automate repetitive tasks so they can focus on writing quality code. Since 2000, the company has aimed to make software development more productive and enjoyable for engineers worldwide. Role overview The Customer Success Engineer - Kotlin Multiplatform (KMP) supports engineering teams as they adopt KMP in real-world projects. This role guides organizations from their first evaluation through to successful deployment. Along the way, it gathers feedback and collaborates closely with JetBrains product teams to help shape the future of KMP. What you will do Work directly with organizations at various stages of KMP adoption, from initial exploration to production rollout. Assist teams in migrating, integrating, and scaling shared codebases using Kotlin Multiplatform. Support teams moving from experimentation to production and help address technical challenges as they arise. Reach out to potential users who could benefit from adopting KMP. Identify each customer’s technical needs, use cases, and any barriers to adoption. Advise on architecture, feasibility, and strategies for implementing KMP. Collect structured feedback and insights from clients. Collaborate with JetBrains product and engineering teams to influence the KMP roadmap and improve available tooling. Common questions you'll help solve What is the safest way to migrate a large Android app to shared logic? How much code sharing is practical or advisable? How can teams address resistance from iOS developers working with Kotlin APIs? What’s the best way to organize a codebase for collaboration across teams? How can teams resolve slower build times after introducing KMP? How success is measured Organizations deliver Kotlin Multiplatform in production environments. Teams increase their use of shared code over time. KMP adoption continues beyond initial trials. User feedback results in tangible improvements to KMP and its tooling. Requirements Experience working with Kotlin, either for Android or backend development. Understanding of mobile architectures on both Android and iOS, especially with Kotlin. Strong communication skills and a knack for problem solving. Background with cloud technologies and CI/CD pipelines. Ability to collaborate effectively within a team-driven environment. Location This position is available in Amsterdam (Netherlands), Berlin or Munich (Germany), or remote within Germany.

Join JetBrains as a Staff Research Engineer specializing in pre-training technologies. In this pivotal role, you will lead groundbreaking research initiatives aimed at enhancing our AI capabilities. Collaborate with a talented team of engineers and researchers to innovate and implement cutting-edge solutions that push the boundaries of software development and AI integration.

About UsAt Vandebron, we are revolutionizing the energy sector by prioritizing sustainability and creating a transparent platform that connects consumers directly with local green energy producers. Since our inception in 2014, we have been committed to fostering a sustainable energy future.As we enter Chapter 2 of our journey, our mission is to guarantee 100% availability of green energy - 100% of the time. We are implementing innovative solutions such as flexible wind and solar energy utilization, Smart EV Charging, and advanced energy storage systems, ensuring a proactive approach to shaping a green future.Join us in creating smart energy solutions - that’s Vandebron.The RoleWe are rethinking our technology infrastructure, and we want you to be part of this exciting transition! As a Senior Backend Engineer, you will play an essential role as we move from a Scala/ZIO foundation to a new generation of services built with Kotlin and Spring Boot. You will be instrumental in developing our future-proof platform, creating scalable and high-quality services that drive Vandebron’s mission for 100% green energy.Collaborating within a dynamic, cross-functional team of engineers, designers, and product stakeholders, you will transform complex energy challenges into efficient backend solutions. Our culture promotes knowledge sharing and experiential learning, making it an integral part of our work environment.ResponsibilitiesCollaborate with fellow engineers to design and develop new microservices utilizing Kotlin and Spring Boot.Design and uphold clean, high-performing APIs that cater to our React and React Native frontends.Produce clean, efficient, and well-documented code that meets our product specifications with increasing autonomy.Engage in all phases of the development lifecycle, including writing tests, conducting code reviews, and ensuring the delivery of high-quality software.Contribute ideas and feedback within your team to cultivate a collaborative and productive work environment.

About Software Improvement Group Software Improvement Group (SIG) helps organizations strengthen their software quality through detailed source code analysis and hands-on consultancy. Our Sigrid platform supports software portfolio governance, giving clients more control over their technology landscape. With guidance from experienced consultants, clients can turn software into a reliable asset instead of a risk factor. Role Overview: AI Research and Development Engineer Based in Amsterdam, this role sits within the CTO Office. The AI R&D Engineer will focus on designing and prototyping AI-driven solutions for software engineering challenges. The work blends experimentation, engineering, and applied research. What You Will Do Develop rapid prototypes and applications powered by AI Run internal experiments using large language models (LLMs), prompt engineering, and AI coding assistants Analyze data and contribute to machine learning projects, especially those related to software quality and development practices This position suits someone who enjoys quickly building and testing new ideas, especially in a team that values experimentation and innovation. Why Join SIG? Work in a small, innovation-focused team with room to experiment Influence SIG’s AI strategy and future product direction See your work shape client-facing solutions and the evolution of our offerings

At JetBrains, we are passionate about crafting exceptional developer tools. Since our inception in 2000, we have dedicated ourselves to creating the most effective and innovative solutions for developers around the globe. With the rise of AI-assisted technology, we are at the forefront of integrating these advancements into our integrated development environments (IDEs). Join our Agentic Models team as a Research Engineer, where you will play a pivotal role in developing multi-step coding agents capable of comprehending extensive codebases, strategizing modifications, utilizing tools, and engaging interactively with users. You will be responsible for designing models, training loops, and evaluation pipelines that drive these intelligent coding agents. Your work will involve merging supervised fine-tuning (SFT) techniques with reinforcement learning (RL) methodologies, coupled with product-oriented evaluations, leveraging our distributed GPU and MapReduce clusters to deploy models across JetBrains products.

Why Join Nebius?Nebius is at the forefront of a new era in cloud computing, specifically tailored to support the burgeoning global AI economy. We equip our clients with innovative tools and resources, enabling them to tackle real-world challenges and revolutionize industries without the burden of exorbitant infrastructure expenses or the need to develop extensive in-house AI/ML teams. Our workforce operates at the cutting edge of AI cloud infrastructure, collaborating with some of the most experienced and visionary leaders and engineers in the industry.Our Work EnvironmentBased in Amsterdam and publicly listed on Nasdaq, Nebius boasts a global presence with research and development centers across Europe, North America, and Israel. Our team of over 1400 includes more than 400 highly qualified engineers with expertise in both hardware and software engineering, complemented by a dedicated in-house AI R&D team.The RoleWe are excited to announce a 3–6 month Early Career program within our AI R&D team. As an AI Researcher, you will collaborate with seasoned researchers to address challenges in large language models (LLMs), reinforcement learning, and agentic systems. We seek early-career talents to assist in research on:Reinforcement learning for agents and reasoning modelsDeveloping reinforcement learning environmentsEfficient model distillation and evaluationYour Responsibilities Will Include:Designing and executing experiments to train LLMs and related modelsAnalyzing experimental results and documenting findingsWriting and maintaining code for data mining, processing, and model evaluationCollaborating with team members to explore innovative solutions

Join Nebius and Shape the Future of AINebius is pioneering a transformative approach to cloud computing, dedicated to empowering the global AI economy. Our mission is to provide the essential tools and resources that enable our clients to tackle real-world challenges and revolutionize industries, all while minimizing infrastructure costs and the necessity of extensive in-house AI/ML teams. Our talented workforce operates at the forefront of AI cloud infrastructure, collaborating with some of the most innovative and experienced leaders and engineers in the industry.Our Work EnvironmentLocated in Amsterdam and publicly listed on Nasdaq, Nebius boasts a global presence with R&D centers across Europe, North America, and Israel. Our diverse team, comprising over 1,400 employees, includes more than 400 highly skilled engineers, equipped with deep expertise in both hardware and software engineering, as well as an in-house AI R&D team.We are on the lookout for a Staff or Principal Applied AI Researcher to join our rapidly expanding team, focused on developing an agent-native search platform—the vital web access layer for AI systems.Unlike traditional search methodologies, we are innovating how AI agents—not humans—access, retrieve, and reason over information available on the internet. As AI increasingly becomes the primary interface for web interaction, this pivotal layer is set to transform the function of conventional search engines.This role involves tackling retrieval and search challenges within entirely new access patterns and scales.Depending on your experience and the responsibilities you take on, this position can be classified at either the Staff or Principal level, granting you ownership over vital aspects of our applied AI research trajectory.You will lead applied research initiatives that directly enhance how AI systems retrieve, ground, and utilize real-world information in production, ensuring that research is closely linked to large-scale deployment.Your ResponsibilitiesEngage in projects at the intersection of search, retrieval, and LLM-based systems, shaping how AI agents engage with the web. This includes designing agent-native retrieval systems (distinct from human search UX), developing systems where LLMs actively query, iterate, and reason over results, and collaborating with cross-functional teams to foster innovation.

Cognite is at the leading edge of industrial digital transformation, creating innovative AI and data solutions that tackle some of the globe’s most challenging and impactful issues. With a rich industrial background and an extensive array of AI capabilities, including low-code AI agents, Cognite is dedicated to accelerating digital transformations to enhance operational efficiencies.Our ambitious goal is to unlock $100 billion in customer value by 2035, redefining the operational landscape of global industries.

As a Client Value Partner in Digital Technology at Celonis, you will play a pivotal role in driving value for our clients through innovative digital solutions. Your expertise will guide organizations in leveraging our cutting-edge technology to transform their operations and achieve remarkable outcomes. You will collaborate closely with cross-functional teams to ensure client success and satisfaction, while also identifying new opportunities for growth.

Join Vattenfall as a Strategic Value Manager in our Marketing Decisioning team, where you will play a pivotal role in shaping our marketing strategies and enhancing customer engagement. Your expertise in data-driven decision-making will be essential in driving our marketing initiatives forward. Collaborate with cross-functional teams to develop innovative marketing solutions that align with our business objectives.

At JetBrains, we are passionate about code. Since our inception in 2000, we have dedicated ourselves to creating the most powerful and effective developer tools available. By automating routine checks and corrections, our tools accelerate production processes, allowing developers to innovate and create freely.We are seeking a Research Engineer to take ownership of the training stack and model architecture for our Mellum LLM family. This role is challenging yet rewarding: your mission is to enhance the speed, cost-efficiency, and stability of large-scale training. You will profile, design, and implement modifications to the training pipeline, from architecture to custom GPU kernels as necessary.As a valuable member of our team, you will:Enhance end-to-end performance for multi-node LLM pre-training and post-training pipelines.Identify performance bottlenecks using tools like Nsight Systems/Compute and resolve them through compute/communication overlap, kernel fusion, scheduling, etc.Design and assess architectural choices, including depth/width, attention variants such as GQA/MQA/MLA/Flash-style, RoPE scaling/NTK, and MoE routing/load-balancing.Develop custom operations with Triton and/or CUDA, integrate with PyTorch extensions, and contribute upstream when feasible.Maximize memory/performance enhancements using FSDP/ZeRO, activation checkpointing, FP8/TE, tensor/pipeline/sequence/expert parallelism, and NCCL tuning.Ensure robustness in large-scale runs by constructing elastic and fault-tolerant training setups, strengthening checkpointing, enhancing reproducibility, and improving resistance to preemption.Maintain a fast data path through streaming and sharded data loaders as well as tokenizer pipelines, while improving overall throughput and cache efficiency.Establish appropriate metrics, create dashboards, and consistently drive improvements.Efficiently run both pre-training and post-training processes (including SFT, RLHF, and GRPO-style methods) across substantial clusters.We’re excited to welcome you on board if you possess:Expertise in PyTorch and PyTorch Distributed, with experience running multi-node jobs using dozens to hundreds of GPUs.Hands-on experience with Megatron-LM/Megatron-Core/NeMo, DeepSpeed, or substantial FSDP/ZeRO knowledge.Strong profiling skills (Nsight Systems/Compute, nvprof) and familiarity with NVTX-instrumented workflows.Proficiency in GPU programming with Triton and/or CUDA, including the ability to write, test, and debug kernels.A solid grasp of NCCL collectives, as well as topology and fabric effects (IB/RoCE), and their implications in performance traces.

Location: Amsterdam, Netherlands Company: Wiz Inc. Role: Senior Business Value Consultant - Central / North About Wiz Wiz is a cloud security company trusted by security teams worldwide. The team includes professionals from over 20 countries, working together to protect the infrastructure of a broad client base. More than half of the Fortune 100 depend on Wiz to scan and secure over 230 billion files every day. Wiz continues to grow rapidly in a large and evolving market. Read more about our growth. Role Overview The Senior Business Value Consultant will help clients understand the strategic and financial impact of adopting Wiz. This role combines hands-on commercial work with a focus on long-term business outcomes. The consultant will translate complex technical solutions into clear, persuasive value propositions for clients. What You Will Do Value Selling: Create deliverables that show strategic alignment, outline multi-year plans, and build business cases with ROI analysis to support client decisions. Orchestration: Lead discovery sessions to identify customers' current challenges and future needs, helping shape effective solutions.

Role overview airapps is looking for an AI/ML Engineer to join the team in Amsterdam. The main focus of this position is to build and deploy machine learning algorithms that enhance product features and improve user experiences. Working alongside a collaborative group, this role helps shape technical solutions and takes projects from initial idea through to implementation. What you will do Design and implement machine learning models for practical, real-world use cases Work closely with colleagues to develop algorithms that strengthen airapps services Apply AI and ML expertise to support the company’s technology goals Location This role is based in Amsterdam and requires on-site presence.

Join our innovative team at pinely as a Staff Research Scientist / Principal Deep Learning Scientist, where you'll spearhead groundbreaking AI research initiatives. In this prominent individual contributor role, you will be at the forefront of technical advancements, crafting research strategies that influence the entire team.We are looking for someone with a profound curiosity and a strong history of leadership in AI laboratories. You should possess hands-on experience with neural networks and applied AI research, ready to take the initiative and make tangible contributions to the development and deployment of advanced models.Key Responsibilities:Lead the creation of AI models that underpin all elements of our trading strategies across global markets.Address the ultimate challenge of forecasting the future by “solving” the complexities of financial markets, leveraging your understanding of deep neural networks amidst diverse, noisy, and ever-evolving dependencies.Guide the direction of research and enhance team capabilities through your deep expertise and insights.Participate in all phases of research, from concept generation to deployment, ensuring the seamless integration of new findings into production systems.Qualifications:Experience as a Senior/Staff/Principal Researcher at a prestigious AI lab or as a faculty member (Professor/Lecturer) at a renowned AI research institution (e.g., Stanford, Berkeley, CMU, MIT, Mila, ETH, UofT, Oxford, UCL, NYU, Princeton).Preferred expertise in competitive, application-driven AI domains such as LLMs, reasoning architectures, generative modalities (e.g., video), or mechanistic interpretability.A drive for impactful research depth with a focus on contributing meaningfully to both the team and the wider field.What We Offer:A unique opportunity to make significant contributions across the entirety of our trading portfolio.Competitive compensation with exceptional profit-sharing potential.A research-driven environment where your deep technical insights directly influence outcomes.Flexibility to work part-time alongside your academic lab commitments.A culture that fosters personal initiative, supports exploration of new ideas, and acknowledges outstanding performance.Flexible work options, with the choice of working from our Amsterdam office or fully remotely, along with potential business travel as needed.

About CuspAICuspAI is a pioneering AI company dedicated to unlocking breakthrough materials essential for advancing human progress. While nature has taken billions of years to refine molecules, we leverage the power of AI to achieve trillion-dollar material breakthroughs in mere months instead of millennia. Our founding team is recognized as the most cited globally, featuring elite researchers in AI, chemistry, and engineering.We tackle some of the most pressing and complex challenges, including energy solutions, clean water access, future computing technologies, and carbon capture. This is merely the beginning of what our innovative 'search engine' for next-generation materials can achieve.Join our diverse and forward-thinking team at the intersection of AI and materials science, where your contributions will foster impactful partnerships and drive innovation, scalability, and collaboration across industries. Your work is significant—let’s make it count.Be part of the on-demand materials revolution. Join us!