Senior Backend Engineer, Buyer (AI)

Location: Berlin, Germany; hybrid work with 2 recommended office days per week

Annual gross salary: €87,600–€118,500 EUR

Company

hirify.global is a second-hand marketplace connecting millions of members across more than 20 markets, with additional shipping and payment businesses across Europe.

What you will do

• Design, implement, and maintain scalable, reliable, and secure backend systems for content visibility and search.
• Lead system design reviews, technical decisions, team-level initiatives, and domain integrations with Search and Recommender relevance teams.
• Build and roll out A/B-tested features for more than 80 million users, including unified content visibility experimentation and analysis platforms.
• Own service performance, stability, observability, SLIs, SLOs, and on-call operations.
• Collaborate with engineering, product, analytics, SRE, and other stakeholders on feasibility, risks, estimates, and roadmap direction.
• Mentor engineers and promote engineering best practices.

Requirements

• Extensive backend engineering experience designing and building scalable, distributed, and highly available systems.
• Strong backend engineering foundation; the primary languages are Go, Kotlin, Ruby, and Python, with willingness to learn more important than prior experience in every listed language.
• Experience with event streaming platforms such as Kafka, Apache Flink, or comparable technologies for real-time processing and message queueing.
• Experience with continuous integration and deployment pipelines, including tools such as Jenkins.
• Experience with observability and monitoring tools such as Grafana and Kibana, including defining SLIs and SLOs.
• Experience working with relational and in-memory databases.
• Strong collaboration and communication skills with Product, Analytics, SRE, and other cross-functional peers.
• Experience mentoring engineers, giving constructive feedback, and promoting engineering best practices.
• Excellent written and spoken English.
• Participation in an on-call rotation is required.

Nice to have

• Experience with search engines, information retrieval, and ranking optimization technologies such as Vespa, Elasticsearch, or OpenSearch.
• Enthusiasm for AI technologies, daily use of AI tools, and proactive experimentation with AI to improve engineering outcomes.

Culture & Benefits

• Hybrid work with 2 recommended office days per week and remote workation of up to 90 days per year in the EU; up to 21 days can be spent globally, with 21 worldwide days for non-EU citizens.
• 30 days of paid annual leave, supplemental private health insurance, life and disability insurance, pension matching, and an Employee Assistance Program.
• Learning budget starting at €3,000 per year and up to 10 working days over two years for development.
• Home office equipment and a budget of up to €540 for workplace furniture, plus a lunch benefit and subsidized Deutschlandticket.
• Share options, shopping budget, discounted gym membership, team-building events, a dog-friendly office, and a personal MacBook.