Join our Trading Technology team in Amsterdam, where you’ll build real-time data systems that directly support Optiver’s trading strategies and market insights. As a\ Quant Developer, you’ll focus on creating scalable, high-performance platforms for real-time analytics, enabling traders to make precise, data-driven decisions across various products. At Optiver, technology drives our approach to market-making—whether optimizing for low latency response times or processing massive data volumes with efficiency, even in extreme market conditions. This role offers the chance to tackle complex technical challenges in a dynamic environment, collaborating closely with traders and researchers to advance smarter, more effective trading practices that keep Optiver at the forefront of the industry.

Who we are

At Optiver, our mission is to constantly improve the market by injecting liquidity, providing accurate pricing, increasing transparency and acting as a stabilizing force no matter the market conditions. With a focus on continuous improvement, we participate in the safeguarding of healthy and efficient markets for everyone who participates. As one of the largest market making institutions, we are a trusted partner of 70+ exchanges across the globe.

What You’ll Do:

You’ll be focused on addressing complex challenges in real-time data analytics in high throughput data environments for trading. As a Senior Software Engineer in the Trading Technology team, you’ll develop and optimize scalable systems for data processing and analytics that handle vast volumes of market data. Your work will ensure low-latency data pipelines, high-throughput compute, and robust algorithms—essential for reliability and speed in our trading decision making

Key Responsibilities:

• Develop scalable, reliable data systems that support real-time analytics for trading and large-scale historical analysis

• Partner closely with traders and researchers to deliver actionable insights and meet dynamic data needs across ingestion, storage, and real-time processing

• Drive the development of our data lake and analytics frameworks, enabling immediate access to live and historical data

• Build real-time analytics capabilities to support rapid decision-making in trading operations

• Engineer for resilience and reliability, implementing automated recovery processes and safeguards for high-demand periods

Projects You Might Work On:

• Enhancing research frameworks to enable quick deployment of trading applications and strategy optimizations

• Expanding real-time analytics for high-frequency trading and predictive market insights

• Integrating machine learning models within data pipelines to improve predictive accuracy

Who You Are:

You’re a highly skilled engineer passionate about building sophisticated systems that drive data-driven trading decisions:

• 5+ years of experience in high-performance data systems and infrastructure

• Proficiency in C++ or Python, with a commitment to clean, maintainable code

• Strong understanding of operational excellence in areas like networking, database performance, and system resilience

• Experience with real-time analytics platforms

• Familiarity with big data tools and frameworks, such as Pandas, Polars, PyArrow, Kafka, PostgreSQL, and DeltaTable

• Background in trading or financial markets is a plus, but not required

WHAT YOU'LL GET:

• The chance to work alongside best-in-class professionals from over 40 different countries.
• Our performance based bonus structure is unmatched anywhere in the industry. We combine our profits across desks, teams and offices into a global profit pool fostering a truly collaborative environment to work in.

Alongside this you will get great secondary benefits such as 25 paid vacation days, fully paid first-class commuting expenses, training opportunities, discounts on health insurance, breakfast and lunch facilities, sports and leisure activities, Friday afternoon drinks and even weekly in-house chair massages.

Being highly international, we are accustomed to guiding expats through their relocation, offering competitive relocation packages and providing visa sponsorship where necessary.

HOW TO APPLY:

Apply directly via the form below. If you have any questions feel free to contact our Recruitment team via our recruitment inquiry form.

Please note:

• We do not require any assistance from third-parties including agencies in the recruitment of this role

• We cannot accept applications via email’

DIVERSITY STATEMENT:

Optiver is committed to diversity and inclusion.

This is Adyen

Adyen provides payments, data, and financial products in a single solution for customers like Meta, Uber, H&M, and Microsoft - making us the financial technology platform of choice. At Adyen, everything we do is engineered for ambition. 

For our teams, we create an environment with opportunities for our people to succeed, backed by the culture and support to ensure they are enabled to truly own their careers. We are motivated individuals who tackle unique technical challenges at scale and solve them as a team. Together, we deliver innovative and ethical solutions that help businesses achieve their ambitions faster.

Machine Learning Scientist

Adyen is looking for a Machine Learning Scientist to join our team in Amsterdam, a person sitting at the cornerstone of algorithms, mathematics, and engineering, who can solve problems by designing and implementing production-ready machine learning solutions. You will be responsible for building, developing and deploying algorithms that power data products at Adyen.

We are currently hiring for the following teams:

Insights - Diagnostics: The Insights team is at the core of this platform, providing the world’s largest merchants with the data and analytics they need to optimize their payment performance. Within this, our Proactive Diagnostics initiative acts as a proactive guard for merchant revenue, closing the loop between detecting an anomaly and providing a clear path to rectification. We operate at the intersection of Big Data and actionable intelligence. By leveraging Adyen’s global payment flow, we apply advanced statistical models and Causal Inference to not only detect performance drops but to explain the "why" behind them. We are looking for a Machine Learning Engineer to help us architect the next generation of our diagnostic engine.

Regulatory Reporting Technology: 

Adyen's Regulatory Reporting Tech team is seeking a Machine Learning Scientist to join us in Amsterdam. You will help in further automating and scaling our global regulatory reporting framework to keep Adyen compliant across all markets. Together with the team, you will implement key technical solutions to streamline our regulatory reporting operations. If you have a strong machine learning background and love solving complex problems, we want to hear from you.

In this role, you will: 

• Research, design, implement, train, deploy and monitor machine learning algorithms, either for batch prediction or real-time. Examples include: on-line learning algorithms to pick the best optimization decision in a changing environment, clustering algorithms to group customers/shoppers, supervised and semi-supervised learning methods for inference on risk patterns or graph analysis, representation learning for behavior prediction and monitoring, Anti-Money Laundering (AML) systems and real-time anomaly detection based on time-series modeling;
• Develop orchestrated pipelines for analytical purposes and machine learning training;
• Contribute to ongoing automation efforts for our experiments, training runs, validation runs and monitoring before, during and after deployment. Furthermore, collaborate with MLOps to improve our machine learning tooling;
• Collaborate closely with product managers and business stakeholders to understand requirements, define problems, and frame them as solvable machine learning tasks;
• Explore and analyze large, complex datasets to identify patterns, insights, and opportunities for ML-driven solutions;
• Define key performance metrics, design rigorous experiments (e.g., A/B tests), and perform statistical analysis to validate model performance and quantify business impact;

Who You Are:

• You have 5+ years of experience as a machine learning or data scientist;
• You have experience with the full machine learning model lifecycle in production flows;
• You have experience leveraging a big data framework to create the pipelines needed to feed the models with appropriate data;
• You have a good understanding of software engineering practices as well as data engineering and MLOps principles;
• You have knowledge of data science and statistics and machine learning techniques. These include a strong grounding in statistical inference, machine learning for prediction, and causal inference - Deep Learning experience is a plus;
• You have strong familiarity with the standard data science toolkit, such as (py)spark, (Trino) SQL, Tensorflow, PyTorch, XGBoost/LightGBM, Pandas, MLFlow or similar MLOps frameworks, and Airflow;
• You have an experimental mindset with a launch fast and iterate mentality. Extensive experience with designing and running experiments is essential;
• You are proactively taking the lead in projects, from ideation to deployment. You have experience working with a wide range of stakeholders and can clearly communicate complex outcomes over a wide range of audiences.
• You stay up-to-date with the latest research and developments in the machine learning field, and apply this where valuable.

Our Diversity, Equity and Inclusion commitments 

Our unique approach is a product of our diverse perspectives. This diversity of backgrounds and cultures is essential in helping us maintain our momentum. Our business and technical challenges are unique, and we need as many different voices as possible to join us in solving them - voices like yours. No matter who you are or where you’re from, we welcome you to be your true self at Adyen. 

Studies show that women and members of underrepresented communities apply for jobs only if they meet 100% of the qualifications. Does this sound like you? If so, Adyen encourages you to reconsider and apply. We look forward to your application!

What’s next?

Ensuring a smooth and enjoyable candidate experience is critical for us. We aim to get back to you regarding your application within 5 business days. Our interview process tends to take about 4 weeks to complete, but may fluctuate depending on the role. Learn more about our hiring process here. Don’t be afraid to let us know if you need more flexibility.

This role is based out of our Amsterdam office. We are an office-first company and value in-person collaboration; we do not offer remote-only roles.

This is Adyen

At Adyen, we’re engineered for ambition. We empower our teams with the culture and support they need to own their careers. The people of Adyen are motivated problem-solvers who tackle unique technical challenges at scale, delivering innovative and ethical solutions to help the world’s best businesses achieve their ambitions faster, and we’re looking for a motivated Senior Machine Learning Engineer to join our team in Amsterdam.

Senior Machine Learning Engineer

The Customer Risk team is at the front line of this platform, building the next-generation systems required to assess and mitigate risk in real time. They are responsible for keeping our platform safe, while maintaining a seamless experience for our legitimate global merchants.

They operate at the critical intersection of high-stakes security and massive scale. By leveraging Adyen’s global payment flow, they are building a greenfield risk engine from scratch that moves beyond traditional detection to sophisticated, real-time entity assessment. We are looking for our first Senior Machine Learning Engineer to lead this effort and help architect the future of risk at Adyen.

In this role, you will:

• Lead – Act as the foundational ML Engineer for the Customer Risk team, taking the lead on the next-generation risk system from initial ideation and design to full production deployment.
• Build – Design and scale production-ready ML models for prediction, ranking, and embedding. You will own the end-to-end lifecycle, ensuring that our risk assessments are backed by robust, deep learning systems that can operate at Adyen’s massive scale.
• Architect – Develop the core ML infrastructure required to power our risk engine. You will build and manage the data processing pipelines, model evaluation frameworks, and deployment strategies that allow us to assess risk in real time with high reliability.
• Innovate – Bring our existing ML capabilities to the next level by introducing advanced software design and modular architecture to our modeling domains. You will bridge the gap between pure research and engineering excellence, ensuring our models are as maintainable as they are performant.
• Collaborate – Work closely with a high-performing product team and leadership to drive the risk roadmap. You will translate complex risk signals into clear business outcomes, directly impacting the safety and integrity of the Adyen platform.

Who You Are:

• You have an Engineering-First mindset. You treat Machine Learning systems as core production software, with 5+ years of experience ensuring that prediction, ranking, and deep learning models are as robust and reliable as any other part of the stack.
• You are a Software Craftsperson. You have 5+ years of experience navigating the full software development lifecycle, from initial testing to global launches. You are deeply proficient in Python, Java, or C/C++, focusing on writing clean, production-ready code that scales.
• You are an expert in the ML ecosystem. You have deep, hands-on experience with the standard Python data science toolkit—utilizing frameworks like TensorFlow, PyTorch, and XGBoost/LightGBM for modeling, and Spark, SQL (Trino), and Pandas for large-scale data manipulation.
• You are fluent in MLOps and Infrastructure. You don’t just build models; you operationalize them using MLFlow, Airflow, and Argo-workflows. You are comfortable working within modern infrastructure environments, leveraging Kubernetes and Docker for containerization, and ensuring system health through Prometheus and Grafana.
• You work end to end. You don’t just train models; you build the world they live in. You have 5+ years of hands-on experience designing end-to-end ML lifecycles, including data processing, model evaluation, deployment, and the fine-tuning required to keep systems performing at scale.
• You balance complexity with pragmatism. You possess 3+ years of dedicated software design and architecture experience. You understand how to build modular, maintainable systems in diverse modeling domains for the long-term.
• You are a Technical Leader. You take ownership of the roadmap, moving projects from ideation to production with confidence. You can translate high-level architectural needs into shipping solutions and have a proven track record of launching software products that deliver tangible impact.

Our Diversity, Equity and Inclusion commitments 

Our unique approach is a product of our diverse perspectives. This diversity of backgrounds and cultures is essential in helping us maintain our momentum. Our business and technical challenges are unique, and we need as many different voices as possible to join us in solving them - voices like yours. No matter who you are or where you’re from, we welcome you to be your true self at Adyen. 

Studies show that women and members of underrepresented communities apply for jobs only if they meet 100% of the qualifications. Does this sound like you? If so, Adyen encourages you to reconsider and apply. We look forward to your application!

What’s next?

Ensuring a smooth and enjoyable candidate experience is critical for us. We aim to get back to you regarding your application within 5 business days. Our interview process tends to take about 4 weeks to complete, but may fluctuate depending on the role. Learn more about our hiring process here. Don’t be afraid to let us know if you need more flexibility.

This role is based in Amsterdam. Our culture is built on the foundation of in-person collaboration, where our teams work side-by-side to solve unique challenges and accelerate growth. 

This is Adyen

Adyen provides payments, data, and financial products in a single solution for customers like Meta, Uber, H&M, and Microsoft - making us the financial technology platform of choice. At Adyen, everything we do is engineered for ambition. 

For our teams, we create an environment with opportunities for our people to succeed, backed by the culture and support to ensure they are enabled to truly own their careers. We are motivated individuals who tackle unique technical challenges at scale and solve them as a team. Together, we deliver innovative and ethical solutions that help businesses achieve their ambitions faster.

Data Scientist

Adyen is looking for a Senior Data Scientist with deep expertise in statistical hypothesis testing, experimental design, and quantitative research methods to join the Experimentation Platform team in Amsterdam. We want to significantly increase the breadth of Experimentation at Adyen and that requires cutting-edge statistics. You will help to research and implement innovative hypothesis testing approaches that drive experimentation at industry-leading scale. You will also work with a diverse set of users, advocating and mentoring on best practices in experimental design, interpretation of results, and evidence-based decision-making.

In this role, you will: 

• Research and implement industry-leading statistical methods to provide robust statistical signals across multiple business domains and contexts, optimising for time-to-signal and experiment quality;
• Develop and apply a deep knowledge of Adyen’s specific domain context in order to prioritise statistical methodologies and approaches that maximise business value;
• Stay up-to-date with the latest research and developments in statistical hypothesis testing;
• Collaborate closely with your multi-disciplinary team of backend/frontend/data engineers to help scope and define requirements for new platform features, ensuring statistical methods are integrated appropriately;
• Collaborate with data scientists across Adyen to identify opportunities for the novel application of statistical and data science techniques to challenging problems;
• Work closely with platform users to provide guidance and enable them for success; promoting experiment-driven culture and product development practices.

Who You Are:

• You have 5+ years of experience as a data scientist, including 2+ years working on an experimentation platform (or similar);
• You have a Master’s or Ph.D. in Statistics, Mathematics, Data Science, Computer Science, or a related quantitative field;
• You have a strong theoretical understanding of advanced frequentist and Bayesian hypothesis testing (e.g. sequential testing, e-processes, etc) as well as causal inference techniques and a proven track record of implementing such methods at scale;
• You have experience designing and analysing controlled experiments in an applied setting to provide tangible business outcomes;
• You have experience leveraging a big data framework to create the pipelines needed to gather experiment data;
• You have a strong understanding of software engineering practices as well as data engineering principles;
• You have strong familiarity with the standard data science toolkit, such as (py)spark, Pandas, SciPy, numpy, and Airflow;
• You have an experimental mindset with a launch fast and iterate mentality;
• You have proven experience in leading projects from ideation to deployment. You have experience working with a wide range of stakeholders and can clearly communicate complex outcomes over a wide range of audiences.

Our Diversity, Equity and Inclusion commitments 

Our unique approach is a product of our diverse perspectives. This diversity of backgrounds and cultures is essential in helping us maintain our momentum. Our business and technical challenges are unique, and we need as many different voices as possible to join us in solving them - voices like yours. No matter who you are or where you’re from, we welcome you to be your true self at Adyen. 

Studies show that women and members of underrepresented communities apply for jobs only if they meet 100% of the qualifications. Does this sound like you? If so, Adyen encourages you to reconsider and apply. We look forward to your application!

What’s next?

Ensuring a smooth and enjoyable candidate experience is critical for us. We aim to get back to you regarding your application within 5 business days. Our interview process tends to take about 4 weeks to complete, but may fluctuate depending on the role. Learn more about our hiring process here. Don’t be afraid to let us know if you need more flexibility.

This role is based out of our Amsterdam office. We are an office-first company and value in-person collaboration; we do not offer remote-only roles.

At IMC, technology is not a department; it’s at the heart of everything we do. Developed in-house, our innovative software makes millions of trading decisions daily, and we win by making better and faster decisions than our competition. Our various Python Development teams create scalable business-critical applications, tools and automated tasks to equip IMC’s Amsterdam, London, Zug and Mumbai trading and business support teams.

Your Core Responsibilities

IMC uses a wide variety of technologies. Python is widely used across our tech stack, notably to make it more accessible to our traders, researchers and analysts. As a Python Software Engineer at IMC Amsterdam, you will take part in the development of high-performance trading systems, analytical tools, signals generation, backtesting frameworks, trade management UIs or regulatory surveillance & risk monitoring. Therefore your role will involve collaborating directly and closely with the business and other tech teams, from initially gathering requirements to short iteration cycles to refine the implementation, to integrate user feedback, to voice and implement your improvements and ideas.

All the software you’ll be building is for internal use only, there are no external clients/users and therefore no non-sense requests: the users of your work sit a few meters from you and you have control over the whole development cycle. Curiosity and interest into the trading and financial markets is a key success factor in this role, as you will be working directly on the business logic, in an environment where understanding the business context is primordial.

At IMC we believe in giving a lot of responsibilities quickly, you’ll be working on your goals with a high degree of independence, yet supported by a solid network of mentors, teammates and trading team highly motivated to make sure you are successful and share their passion for trading and technology. In this role, you might end up working on are a wide range of tasks - for example:

• Adding a new signal a trader came up with to our framework.
• Supporting a trading desk in building the data analytics and visualisation tools they need.
• Troubleshooting, debugging or deep diving into performance analysis.
• Teaching others how to use our tech in their own scripts.
• Building and distributing internal python libraries.
• Starting whole new full-stack projects from scratch.

Your Skills and Experience

• We care about 4+ years of working experience as a Software Engineer.
• Deep technical knowledge of Python, you understand its internal workings and know its strength and limitation. We use a range of Python libraries and frameworks (such as FastAPI (AsyncIO), APScheduler, Pandas, Polars, RQ, Pytest, Tensorflow, scipy, xgboost, scikit-learn, numpy, numba, celery).
• Experience with DevOps, databases, big data or frontend frameworks is a plus. (Some examples of tools we frequently work with: Kubernetes, Helm, Docker, Gitlab CI, TypeScript, React, Redis, PostgreSQL, Mongo, Dremio, Apache Iceberg, HDFS, Kafka, Apache Arrow/Parquet).
• A critical mindset and the ability to challenge ideas and solutions, to not take things for granted, validate assumptions and dig into the details to find and cover all corner cases. You’re not afraid to ask questions and to speak up.
• Experience working with financial data is a must, ideally in the financial services industry. The nature of this role requires both affinity and experience to this type of data.

Our tech stack includes an ever-evolving range of systems and technologies, and our engineers have the freedom to choose the best solution for the problem at hand. If a new technology has the potential to add value, we’ll actively invest in exploring, adopting and developing it. 

The Connectors team is the bridge between ClickHouse and the entire data ecosystem. We build and maintain the connectors that make ClickHouse accessible to millions of developers and data practitioners worldwide. Our work spans from low-level database integrations to high-level data visualization plugins, ensuring that ClickHouse seamlessly integrates with the tools our users already know and love.

We're responsible for the official data connectors (Kafka, dbt, Spark, Flink, Beam, Fivetran), and integrations with leading visualization platforms (Grafana, Tableau, Power BI, Metabase).

What will you do?

As a Senior Software Engineer specializing in JVM-based frameworks, you'll serve as a core contributor, owning and maintaining critical parts of ClickHouse's Data engineering ecosystem. This role sits at the intersection of high-performance database engineering and developer experience, where you'll craft tools that enable Data Engineers to harness ClickHouse's incredible speed and scale.

You'll own the full lifecycle of data framework integrations - from the core database driver that handles billions of records per second, to SDKs and connectors that make ClickHouse feel native in JVM-based applications. This isn't just about writing code; you're building the foundation that thousands of Data engineers rely on for their most critical data workloads.

Your work will directly impact how companies process massive datasets, from real-time analytics platforms ingesting millions of events per second to observability systems monitoring global infrastructure. You'll collaborate closely with the open-source community, internal teams, and enterprise users to ensure our JVM integrations set the standard for performance, reliability, and developer experience.

About you:

• 6+ years of software development experience focusing on building and delivering high-quality, data-intensive solutions.
• Proven experience with the internals of at least one of the following technologies: Apache Spark, Apache Flink, Kafka Connect, or Apache Beam.
• Experience developing or extending connectors, sinks, or sources for at least one big data processing framework such as Apache Spark, Flink, Beam, or Kafka Connect.
• Strong understanding of database fundamentals: SQL, data modeling, query optimization, and familiarity with OLAP/analytical databases.

A track record of building scalable data integration systems (beyond simple ETL jobs)

• Strong proficiency in Java and the JVM ecosystem, including deep knowledge of memory management, garbage collection tuning, and performance profiling.
• Solid experience with concurrent programming in Java, including threads, executors, and reactive or asynchronous patterns.
• Outstanding written and verbal communication skills to collaborate effectively within the team and across engineering functions.
• Understanding of JDBC, network protocols (TCP/IP, HTTP), and techniques for optimizing data throughput over the wire.
• Passion for open-source development.

Bonus points for:

• Prior contributions to open-source projects: actively engaging with the OSS community, advocating for users, and influencing the evolution of the core system through your contributions.
• Familiarity with ClickHouse or similar high-performance data platforms.
• Working knowledge of Python, especially in data engineering contexts (e.g., Pandas, PySpark, Airflow), and ability to contribute to Python tooling when needed.

We are Gelber Group -- Passion for Trading. Powered by Technology.

Gelber Coöperatief is a subsidiary of Gelber Group, LLC.  Headquartered in Chicago with offices across the United States and Europe, Gelber has set the bar as one of the industry’s most innovative and enduring proprietary trading firms for more than 40 years.  Our success derives from a relentless pursuit of new trading ideas and careful attention to technology.  

We have a culture of entrepreneurship, innovation, and collaboration. We empower each member of our team to have a meaningful impact from the start.  We employ a flat organizational structure and focus on meritocracy. 

As a Trader for Gelber Coöperatief in our Amsterdam office, you will have an opportunity to play a critical role as we expand our footprint throughout Europe.  You will be joining a successful trading desk with over a decade of experience in a variety of asset classes and a wide range of trading styles.  You will work side by side with a talented and experienced team to capitalize on the market and build out a growing trading desk.  This role is for someone who flourishes in a fast-paced environment, has a strong work ethic, a competitive attitude, and a proven record of profitability in a trading position for at least two years.

This position is located in Gelber’s Amsterdam office, executing proprietary trading strategies and conducting data analysis to improve performance.  

What you’ll do:

• Generate alpha using proprietary trading strategies
• Manage your own trading book with access to multiple exchanges and asset classes
• Share information regarding market developments across your trading team
• Conduct research to develop new alpha strategies to broaden the groups trading techniques
• An active participant in advancing the groups proprietary python libraries

What you’ll need:

• Bachelor’s degree in Computer Science, Math, Finance, Engineering, Statistics or a related field
• Experience using Python (Pandas, NumPy), Excel and SQL
• Proven track record of profitability as a trader for at least one year
• Proficiency in numerical and statistical analysis concepts
• Excellent problem-solving skills and ability to learn, understand and apply new concepts quickly
• Proven self-starter
• Excellent written and verbal communication skills in English are required and other languages are always welcome

Benefits Highlights

Gelber Amsterdam offers a wide range of benefits to full-time employees.  Our benefits offering includes:

• Health insurance reimbursement
• Pension
• Health club membership reimbursement
• Generous vacation time (25-day accrual in first full calendar year of employment; prorated accrual in initial year)
• Social events including team dinners and company parties
• Charitable giving and company matching opportunities
• Casual, relaxed dress code
• Located in a major Amsterdam business district with excellent transportation connections