About the role: OfferUp is looking for a backend developer to join the Trust & Safety team. The team builds systems that detect and prevent fraudulent behavior in our marketplace. These systems help to maintain our community guidelines and support our partner team's growth and business strategies. The key problems we focus on are Account takeovers, Phishing, Payment chargebacks, and Prohibited Items. At many organizations, your role begins and ends with the code. On our team, we're different. You own a feature from concept to fruition. Your responsibilities will include everything from writing well-architected and thoroughly tested code, to rolling out the feature by analyzing metrics. You also get to take ownership beyond your technical area by working with cross-functional team members. This role is only available outside the US and not available to any individual based within the US or any US territory. Here's more of what you will get to do: Work collaboratively with cross-functional teams (risk analysts, data science, and operations) to design and implement new features Analyze the latest attacker techniques and apply solutions to detect them holistically and stop them proactively Drive engineering and operational excellence across the Trust & Safety engineering team Collaborate with OfferUp-wide engineering teams to improve processes, surface common pain points, develop solutions, and evangelize best practices Develop highly scalable classifiers and tools leveraging machine learning, data regression, and rules-based models Identify when to replace and when to rebuild legacy systems Participate in reasonable on-call rotations with the rest of the team Support, mentor, and help other engineers on the team You'll thrive in this role if you have: 3+ years of professional software engineering experience, of which at least 1 was devoted to web services Experience performing data analysis and translating the results into business recommendations Strong coding skills in Java, Python, Scala, Golang or any other modern programming language coupled with strong knowledge in object-oriented design and microservices architecture BS or MS in Computer Science or equivalent experience Excellent communication skills, both written and spoken (fluency in English required) Helpful, but not required: Experience with Identity, authentication, and authorization systems Experience with anomaly detection, bot detection, machine learning, pattern recognition and/or data mining Experience in building microservices Experience with cloud infrastructure AWS About OfferUp: OfferUp is the largest mobile marketplace for local buyers and sellers in the U.S. We are changing the way people buy and sell in their communities by providing a uniquely simple and trusted experience on our iOS and Android apps. Our goal is to be the platform of choice for local commerce by connecting buyers and sellers through an interface that makes selling an item as easy as snapping a picture from a mobile device. OfferUp was founded in 2011 and has grown to serve local markets across the U.S. with more than 1 in 5 adults using OfferUp in 2022. More About OfferUp At a Glance Top 10 Shopping app in the App Store and Google Play Store for three years 15%+ of adults in several markets use OfferUp every month (LA, Miami, Phoenix, Seattle, Las Vegas, Riverside, Orlando) OfferUp works directly with nearly 2000 US law enforcement agencies to build trust in local communities #J-18808-Ljbffr