Senior Go Backend Developer (Supply Integrations Team) (f/m/d)

adjoe builds the technologies behind mobile apps growth and monetization. With our core product **Playtime Arcade**, we've become the global leader in rewarded advertising, an ad unit built on a simple premise: users earn real in-app rewards for engaging with new apps. The result is one of the most effective value exchanges in adtech, connecting advertisers and publishers with over 770 million users annually.

**Processing 2+ million daily interactions between adjoe's reward engine and its global publisher network**

The Supply Integrations team builds and operates the services that ensure every user reward is calculated, verified, and delivered, whether that means firing a cryptographically signed **HTTP callback** in milliseconds or transferring loyalty points through a partner's **OAuth-secured payment API**. Every callback that lands on time is a reward delivered, a publisher retained, and revenue protected.

The team's production surface spans a set of services connecting adjoe to a global publisher network. **S2S Payout Callbacks** deliver real-time reward notifications with **40+ configurable parameters,** secured by per-publisher cryptographic signatures. The **Payout Adapter** integrates directly with enterprise partner payment systems, handling **OAuth2** flows, **mTLS**, **HMAC signatures**, and retry logic to guarantee delivery. Our External Statistics API aggregates data from Druid, Athena, and DynamoDB into self-serve publisher dashboards and daily reports. All of this is backed by Go microservices communicating over Kafka and SQS, with state managed in **DynamoDB** and **MySQL**, processing over **2 million interactions every day** without missing a beat.

• Build and maintain our +99% Go microservice architecture—interfacing with our TypeScript/React frontend—to reliably handle 2+ million daily publisher interactions and scale beyond hundreds of millions of monthly active users.
• Design asynchronous microservice communication using event buses like Kafka, SQS/SNS, and Kinesis and build pipelines to collect billions of daily API events and aggregate them into our data lake for sub-second querying.
• Optimize queries across hundreds of terabytes of data across DynamoDB, MySQL, Druid, and Athena to reduce API response times and expose transparent, well-documented open APIs to enterprise partners.
• Partner directly with our Data Science team to translate and integrate machine learning algorithms into adjoe's core application, optimizing real-time ad targeting.
• Actively participate in peer code reviews and technical knowledge sharing across an international backend engineering team.

• 5+ years of backend development experience, including at least 3 years writing Go in production distributed environments
• Hands-on experience designing asynchronous microservice communication using event buses like Kafka, SQS/SNS, and Kinesis
• Understanding of database internals and low-level web standards (HTTP protocol, Encoding, Regular Expressions)
• Ability to quickly grasp complex technical topics and applied mathematics
• Fluent and precise communication in spoken and written English
• Hands-on experience with Terraform (Infrastructure as Code), Docker containerization, or serverless infrastructure

• Own projects with impact on 770M users and push adtech boundaries.
• Ship solutions multiple times a day, learn from results, and keep momentum.
• Solve problems openly and collaborate across teams.
• Grow with a diverse, global team of people from over 40 different countries that learn from each other.
• Celebrate wins, enjoy daily victories, and bring your energy.
• Relocation support to Hamburg, Germany for those ready to join our team.