Senior Backend Engineer — Go/Kotlin for Global Ops

Wolt; Helsinki; On-site; EUR 90,000 - 120,000; Full time

Job summary

Wolt is seeking a Senior Backend Engineer to own production systems end-to-end, primarily using Go or Kotlin. You will design, build, and operate backend services supporting inventory, purchasing, and fulfillment across a distributed tech stack.

The role emphasizes data-heavy systems, observability, and collaboration with product, data science, and operations teams to drive scalable, reliable solutions. Helsinki-based, with potential for related markets.

Qualifications

• Strong experience designing, building, and operating production backend systems.
• Proficient in Go, Kotlin, or another modern backend language.
• Experience owning services end-to-end, including design, deployment, monitoring and production operations.
• Solid knowledge of backend and distributed systems fundamentals, APIs, databases, and observability.
• Comfort with data-heavy systems and technologies such as Kafka and Snowflake.
• Able to navigate ambiguous problems and deliver incremental, pragmatic solutions.
• Effective communicator and collaborator with engineers, product and data teams.
• Willingness to leverage AI-assisted development tools where appropriate.

Responsibilities

• Design, build, and operate backend systems that support inventory, purchasing, warehouse operations, pricing, and fulfillment.
• Own technical solutions from problem definition through implementation, deployment, monitoring and production operation.
• Work on data-heavy systems where software engineering meets forecasting, optimization, and operational decision-making.
• Translate complex business problems into pragmatic, scalable technical solutions.
• Make and influence architectural decisions balancing scalability, reliability, and long-term maintainability.
• Collaborate with engineers, product managers, data scientists, and operations teams to shape solutions and technical direction.
• Improve reliability, observability, scalability, and operational excellence of owned systems.
• Contribute to engineering standards through discussions, reviews, and knowledge sharing.

Skills

Backend design

End-to-end ownership

Go or Kotlin

Distributed systems

APIs & databases

Tools

Kafka

PostgreSQL

MongoDB

Redis

Snowflake

Kubernetes

Docker

gRPC

GitHub Actions

Job description

Wolt is seeking a Senior Backend Engineer to own production systems end-to-end, primarily using Go or Kotlin. You will design, build, and operate backend services supporting inventory, purchasing, and fulfillment across a distributed tech stack.

The role emphasizes data-heavy systems, observability, and collaboration with product, data science, and operations teams to drive scalable, reliable solutions. Helsinki-based, with potential for related markets.