Senior Backend Engineer

We’re building something new within Evolution.
This is not an iteration on an existing product or a role focused on maintaining established systems. It is a chance to help define a new platform from first principles, with the technical bar set by the realities of global scale, real-money transactions, and the need for predictable behavior under load.The system we’re building will operate across regions and process thousands of real-money transactions per second with strict consistency guarantees. Low latency, correctness, performance, and security are not goals we optimize for later. They are design constraints from day one.This role is for engineers who want to shape core technical decisions in a small, high-caliber team. We optimize for talent density, clear thinking, and execution speed, not headcount.
 

 What You’ll DoDefine and evolve the backend technology stack based on system constraints, trade-offs, and long-term maintainabilityDrive architectural decisions across backend services, infrastructure, and the data layerDesign and build systems where correctness, security, and performance are non-negotiableArchitect APIs and services for high concurrency and large volumes of real-money transactionsDesign data models and transaction flows with strong guarantees around consistency and integrityMake informed trade-offs between latency, consistency, and scalability in distributed systemsIdentify bottlenecks early and continuously improve throughput, latency, and reliabilityOwn critical systems end-to-end, from design and implementation to behavior in productionCollaborate with experienced engineers to challenge assumptions, refine designs, and raise the technical barStrengthen engineering quality through code reviews, design discussions, and knowledge sharing 

 This Role Is Likely Not for You IfYou prefer clearly scoped implementation tasks over owning technical directionYou are uncomfortable making decisions with architectural or long-term design impactYour experience with backend systems at scale is limited or surface-levelYou tend to treat performance, scalability, or security as secondary concerns rather than core design constraintsHow To ApplyPlease send:A short note on why this role is a strong fit for youYour resume or LinkedIn profileGitHub, portfolio, or code samples, if available1-3 examples of backend systems or features you’ve built where scale, performance, security, or robustness were central, including the technical challenge, the system context, and your specific contributionOur Benefits areCompetitive salary, pension, health and medical insurance30 paid vacation daysFitness benefit (Friskvårdsbidrag)Professional growthSport activities, parties, team buildingsThis is a 100% on-site position. Based in Stockholm, Sweden.

 Who You AreYou have strong computer science fundamentals and substantial experience building reliable, observable, high-performance backend systemsYou have experience designing and operating high-volume distributed systemsYou think in terms of data integrity, concurrency, failure modes, and long-term maintainabilityYou understand scalability beyond infrastructure alone, including data modeling, caching, consistency, and concurrency controlYou are comfortable making architectural decisions with long-term consequencesYou take ownership of problems and drive them to a reliable outcomeYou are curious, rigorous, and motivated to continuously improve both systems and engineering practicesRelevant ExperienceDesigning backend systems for high-throughput, low-latency, business-critical workloadsDistributed systems design, especially around consistency, partitioning, concurrency, and failure handlingTransactional data modeling and correctness guarantees in financial or otherwise high-integrity domainsAPI and service design for high concurrency and strict reliability requirementsProduction observability, including metrics, tracing, structured logging, alerting, and performance analysisSecurity-minded engineering, including authentication, authorization, secrets handling, secure service communication, and defensive designPerformance engineering across application, database, cache, and network layersOperating services in production with strong reliability and incident ownershipBonus ExperiencePayments, fintech, gaming, trading, or other regulated or real-money transaction domainsMulti-region system design with low-latency routing and strong data integrity guaranteesEvent-driven architectures, messaging systems, and idempotent workflow designPostgres or other strongly consistent data stores in high-write environmentsCaching and data-access strategies under strict correctness constraintsContainerized infrastructure and cloud-native operationsInfrastructure as code and automated delivery pipelinesLoad testing, capacity planning, and performance regression prevention