Senior Developer, Ad Delivery

About the Company Do you want your code to decide what a business bids, wins and earns, several hundredmillion times a day? At Readpeak we are looking for a Senior Developer for Ad Delivery towork on the real-time bidding path at the centre of our platform, where a change you shipthis week shows up in advertiser outcomes and company revenue the next. Readpeak is one of the most advanced programmatic marketing platforms for nativeadvertising globally. We serve some of the finest brands, like BMW, Bosch, Eurocard andover 2000 more in our target markets. With our headquarters in Helsinki and side offices inStockholm, Oslo, Copenhagen, Berlin, Paris, the UK and Switzerland, our team consists ofambitious but relaxed international industry experts. With over 8 billion ads served a year in the Nordics alone and a growth rate over 50% year-over-year, our bidding systems handle hundreds of millions of bid requests every day. Everyone of them is a decision made in milliseconds about whether to bid, how much, and onwhose behalf. About the Role The roleYou will be the second engineer on our ad delivery path, working side by side with the leadwho owns it today.You will pair with them, take real ownership of parts of the path, and end up as someonewho can explain and change any of it. If that sounds like a lot of responsibility, it is, and it isalso the reason this is one of the most interesting engineering seats in European AdTech. Responsibilities You will be the second engineer on our ad delivery path, working side by side with the leadwho owns it today. You will pair with them, take real ownership of parts of the path, and end up as someonewho can explain and change any of it. Work in our OpenRTB bidder: how a bid is formed, how it is shaded, and how pricingresponds to what the auction returns Ship pricing and bidding ML experiments against live traffic, then measure them honestly Own billable event processing, where clicks and completed video views become revenue Build the observability that tells us, quickly, when a bidding change did something we didnot intend Work on refactoring the NodeJS codebase to domains that enable us to eventually moveto an optimized, Rust-based solution Help us open new channels by making our inventory buyable as deals inside the majordemand-side platforms Qualifications 5+ years of professional experience in software engineering or back-end development Experience in ad tech, especially anything auction-side: OpenRTB, header bidding,supply-side or demand-side platforms Required Skills Computer science fundamentals, software engineering best practices and strongprogramming skills (Node.js/TypeScript or a similar language, Rust as a bonus) Experience with real-time or low-latency production systems, and a feel for where themilliseconds go A track record of shipping in short iterations, with the testing and rollout habits that makethat safe on a revenue path Comfort with data that is noisy, delayed and biased, and with statistics good enough totell a real result from a hopeful one Solid understanding of CI/CD pipelines, DevOps practices, deployment automation, andinfrastructure-as-code Strong experience with AWS (ECS/EKS, EC2, RDS, SQS, CDK), comfortable helping outon the DevOps side Our development team uses thelatest AI tools and experience with AI enabled development is essential. Preferred Skills Bonus points: Experience with bandits, bid shading, pricing or other applied optimisation in production Familiarity with MLOps systems in production Pay range and compensation package This role is Helsinki-based and you should live in the Helsinki capital region or nearby 500€ HSL commute benefit when working at the Helsinki office A company trip or two per year with the whole team (we just came back from Italy) Free lunch every Wednesday Stock options are available, so you'll benefit from the success you help build We have an extensive healthcare package for team members working from Helsinki Equal Opportunity Statement We are very relaxed and easy-going, yet focused and hard-workingAs part of the journey, we create great memories with the team that you will never forgetIf you meet our criteria and want to be part of this journey, we would love to talk with you! Who We're Looking For We are looking for someone who ships. This role suits an engineer who works in fast, small iterations, puts changes in front of real traffic, reads what happened and goes again. Our feedback loops are short: services and system changes can be safely tested against live traffic with a low barrier to experimentation, so the distance from an idea to a measured result is days.You should enjoy systems where correctness and latency both matter, and where being wrong is directly measurable in money. Stack you will be working with Node.js/TypeScript with some Rust to come OpenRTB AWS (core infrastructure) Python GitLab Clickhouse Good to know This role is Helsinki-based and you should live in the Helsinki capital region or