Backend Engineer

Join to apply for the Backend Engineer - Anti-Fraud role at Prelude. 4 days ago Be among the first 25 applicants About Prelude Prelude is on a mission to transform how companies onboard and authenticate users. We help businesses verify their users with greater efficiency, less friction, and stronger security — ultimately increasing conversion rates and reducing costs. Our flagship product focuses on authentication, enabling companies to send OTP codes with the best price‑to‑conversion ratio available. We do this by dynamically selecting the most effective delivery channel (e.g. SMS via the optimal carrier vs. WhatsApp), while actively blocking costly spam and fraud attempts that traditional providers often miss. Founded just two years ago, Prelude has already achieved healthy financials and strong product‑market fit. But authentication is only the beginning. With a pipeline of bold, market‑defining ideas, we’re building the platform for trust at scale — and we’re excited to shape the future of onboarding and user verification with you. About The Role You’ll start by working on Prelude’s anti‑fraud system. Here, you will analyse traffic patterns and work to help battle fraudulent attacks of all natures, for our customers. You will take part in the continuous effort of making it better, faster and more reliable by working closely with engineers, a product designer and of course, customers. As a new engineer within the Prelude Team, you have the opportunity to rapidly grow your skillset by working in a position that allows you to perform a wide array of tasks that extend from designing distributed systems, full‑stack development and infrastructure management. What you will do Building and scale a distributed system based on AWS technologies such as DynamoDB, SQS, Redshift and Lambdas and using the Go programming language. Work on the next version of the Prelude anti‑fraud system which we strive to be industry‑leading in terms of usability, performance and functionality. Ensure that our services are scalable, extensible, reliable, and performant. Help deploy and scale our fraud prevention model to hundreds of large customers. Develop and maintain internal tools to increase our efficiency. Deploy and scale our fraud prevention model to hundreds of large customers. Design and implement anti‑fraud measures to detect and mitigate fraudulent authentication attempts. Develop and execute complex SQL queries for data analysis, fraud detection, and customer insights. Build statistical models and analytics dashboards to track user authentication trends and performance. Deploy and fine‑tune machine learning models to enhance fraud detection and authentication workflows. Develop and maintain internal tools to increase efficiency and automate key processes. Interact with customers daily to assist them and build features tailored to their needs. About you You have experience working with large datasets, writing complex SQL queries, and analysing authentication patterns. You have a strong technical background, including 4+ years of experience designing and engineering large‑scale systems. You have strong coding skills in Go. You prefer simple solutions and designs to complex ones, and have a good intuition of what will last a decade and scale. You have a product‑led mindset: you code for the output, not for the process. You are fluent in English. Nice to have Experience working with Rust, TypeScript or any other highly scalable language is a plus. You have experience in anti‑fraud engineering and can design systems to detect and prevent fraudulent activities. What we offer Competitive compensation package with BSPCEs. Hybrid working style: 3 days at the office and 2 days at home, with 4 weeks of remote per year. We will provide you with the gear you need for your role (a laptop and a phone, for on‑call rotations). An annual offsite in a great location (last one was at La Pradet). Interview process The interview process will start with a 30‑minute introductory call followed by two technical assessments. You will then be invited to our offices in Opera, where we will work together on a small practical project for about an hour, followed by a system design problem and an informal discussion about your past experiences and your working style. We don’t expect you to ace all these stages; we will evaluate your creativity and how you approach difficult problems. You should consider applying even if you don’t meet all the criteria. #J-18808-Ljbffr