Job Overview
Location
Bay Area, CA, United States of America
Job Type
Full-time
Category
Machine Learning Engineer
Date Posted
February 24, 2026
Full Job Description
đź“‹ Description
- • Join Block's Risk Signals & Controls team as a Staff Machine Learning Engineer and play a pivotal role in safeguarding Block's ecosystem by developing and deploying robust machine learning solutions. Our mission is to empower Block's critical risk decisions with highly reliable signals and efficient, cutting-edge models that adapt to an ever-evolving data landscape. You will be instrumental in building and maintaining the sophisticated infrastructure that processes thousands of transactions per second in real-time, enabling rapid fraud detection and enhancing model effectiveness.
- • This role offers a unique opportunity to collaborate closely with a diverse group of talented ML Modelers and Software Engineers across various Block teams. Your work will directly impact the optimization of the signal lifecycle, focusing on elevating signal quality, minimizing noise, and accelerating the time-to-insight for crucial risk assessments. We are a forward-thinking team, constantly exploring new avenues and pushing the boundaries of what's achievable in machine learning for risk management.
- • As a Staff Machine Learning Engineer, you will be responsible for the end-to-end design, development, and maintenance of scalable data pipelines. These pipelines will be crucial for ingesting both third-party and internal Block data, enriching our feature store, and significantly enhancing our modeling capabilities. You will architect and implement elegant ML pipelines and services, experiment with novel approaches, and meticulously productionize these solutions to operate reliably at scale.
- • A key aspect of your role will involve building sophisticated tooling designed to streamline the maintenance of our features and models. This tooling will drive significant efficiencies in our fraud detection processes, allowing us to respond more effectively to emerging threats. You will work hand-in-hand with ML Modelers, acting as a technical partner to identify, integrate, and operationalize new data sources, innovative heuristics, and advanced machine learning models.
- • You will tackle complex technical challenges inherent in operating at Block's scale, fostering a collaborative environment with colleagues distributed globally. A strong emphasis will be placed on applying ML and engineering best practices to shape and refine how Block develops, tests, deploys, and maintains its ML platform solutions. This includes establishing and promoting standards for code quality, testing, monitoring, and operational excellence.
- • Ensuring the integrity and completeness of our data is paramount. You will implement automated validation checks, robust monitoring systems, and proactive alerting mechanisms to maintain high data quality standards. This proactive approach is essential for the reliability of our risk models and decision-making processes.
- • We embrace a culture of ownership. You will own your solutions from the initial design phase through to ongoing operation, including being part of the on-call rotation to address any production issues. This shared responsibility ensures that we collectively maintain the high availability and performance of our critical systems.
- • This role demands a blend of deep technical expertise, strategic thinking, and strong leadership. You will contribute to shaping the future of AI and ML practices within Block, driving the adoption of AI-first workflows, coaching leaders on scalable use cases, and embedding principles of quality and accountability into team norms. Your ability to reason about complex, distributed systems operating at high scale will be crucial for success.
- • You will leverage your proficiency in machine learning techniques, experimental design, and data engineering to build impactful solutions. Strong programming skills in languages such as Python, Kotlin, and familiarity with ML frameworks like TensorFlow or PyTorch are essential. Your ability to communicate clearly and concisely, both verbally and in writing, will facilitate effective asynchronous collaboration across multiple time zones and diverse teams.
- • We value general engineering skill and versatility. While familiarity with our technology stack is beneficial, a willingness to learn and adapt is highly prized. You will have the opportunity to work with and learn technologies such as Python, Java, Kotlin, HTTP, JSON, gRPC, Protocol Buffers, AWS, Databricks, Kubernetes, MySQL, DynamoDB, Kafka, Spark, Prefect, and Airflow.
- • This is an opportunity to make a significant impact on the security and integrity of Block's financial ecosystem, working on challenging problems with a talented and dedicated team.
🎯 Requirements
- • 12+ years of experience in software development with a proven track record of technical initiative and leadership in machine learning projects.
- • Demonstrated ability to shape and drive the adoption of AI/ML practices within teams and organizations, including coaching leaders and identifying scalable use cases.
- • Proficiency in machine learning techniques, experimental design, and data engineering, coupled with strong programming skills in languages such as Python, Kotlin, TensorFlow, or PyTorch.
- • Experience designing, building, and maintaining scalable data pipelines and ML pipelines/services, with a focus on productionizing solutions.
- • Ability to reason about complex, distributed systems at high scale and ensure data quality through automated validation, monitoring, and alerting.
- • Strong communication skills, particularly written communication for effective asynchronous collaboration across time zones.
🏖️ Benefits
- • Comprehensive Healthcare coverage (Medical, Vision, and Dental insurance).
- • Health Savings Account (HSA) and Flexible Spending Account (FSA) options.
- • Retirement Plans with company match.
- • Employee Stock Purchase Program (ESPP).
- • Generous Paid Time Off (PTO), including 12 paid holidays and paid sick leave.
- • Paid parental and caregiving leave.
- • Robust Learning and Development resources.
- • Wellness programs, including access to mental health support, 1:1 financial planners, and a monthly wellness allowance.
- • Paid Life insurance, Accidental Death & Dismemberment (AD&D), and disability benefits.
- • Eligibility for Block's equity plan and potential sign-on bonus.
Skills & Technologies
Python
Java
Kotlin
MySQL
DynamoDB
Senior
Remote
About Block, Inc.
Block, Inc. builds financial technology and commerce tools for businesses and consumers. Its ecosystem spans Square point-of-sale systems, Cash App peer-to-peer payments, Afterpay buy-now-pay-later services, and Bitcoin-focused initiatives including TBD and hardware wallets. Operating globally, the company offers integrated hardware, software, and banking solutions that enable sellers to accept payments, manage inventory, obtain loans, and sell online, while giving individuals access to digital banking, stock investing, and cryptocurrency services.
