Location: Remote
Type: Contractor
Scanz has been building real-time trading technology for nearly two decades, powering serious traders around the world. We specialize in complex, high-performance systems that operate at scale in the fintech and capital markets space.
At Scanz, innovation is grounded in education, curiosity, and collaboration. We foster a culture of continuous self-improvement and actively encourage out-of-the-box thinking. Our distributed teams work closely together to build the next generation of financial software used by traders of all experience levels—from industry professionals to first-time investors.
The RoleWe’re looking for a Senior Backend Developer to join our engineering team and help design, build, and scale robust server-side systems and data pipelines. You’ll work primarily with Kotlin and Spring WebFlux in a highly concurrent, event-driven environment processing millions of operations per day.
Strong Kotlin experience is preferred, but we’re equally open to seasoned Java developers who are motivated and able to transition quickly to Kotlin.
This is a core role with real ownership: you’ll help shape architecture decisions, performance strategy, and system reliability in a production-grade fintech platform.
What You’ll DoDesign and implement server-side services using Kotlin, Java, and Spring WebFlux
Build and maintain fault-tolerant, high-throughput data pipelines
Develop and maintain high-performance APIs
Collaborate closely with frontend engineers to integrate user-facing features
Contribute to PostgreSQL schema design and optimization
Improve system throughput and reliability through profiling, tuning, and performance testing
Scale services horizontally in a cloud-native environment
Integrate performance and reliability checks into CI pipelines
Participate in weekly standups, code reviews, and architectural discussions
Strong proficiency in Kotlin and/or Java
Solid experience with Kotlin coroutines and flows
Deep understanding of Spring WebFlux, Reactive Streams, and backpressure
Experience building distributed, fault-tolerant systems
Strong problem-solving and analytical skills
Comfortable working asynchronously across time zones
Excellent communication skills (Slack, Loom, async collaboration)
Hands-on experience with:
PostgreSQL
AWS and cloud-native architectures
Docker and Kubernetes
Strong grasp of the testing pyramid (unit, integration, E2E)
Willingness to actively participate in code reviews and technical discussions
Kotlin, Java
Spring WebFlux, Ktor Server
Kotlin Coroutines
RSocket
Ktor Client
kotlinx.serialization
Quartz
Kotest, JUnit
Gradle
Kotlin Multiplatform
React (Hooks)
TypeScript
SharedWorker
NPM
Gradle
AWS (including S3)
Docker & Kubernetes
Prometheus & Grafana
Jenkins
GitHub
