Backend Developer

Valerii Riaboshapko

Pragmatic Senior / Lead Backend Engineer with 9+ years of experience designing high-throughput distributed systems and AI-driven products using Kotlin, Scala, and Python. A hands-on technical leader who combines strong architectural execution with a product-driven mindset to deliver scalable systems, lower latency, and optimize infrastructure costs.

About

Throughout my career, I have driven engineering initiatives across AI, fintech, and cybersecurity domains. As Backend Lead, I executed full-scale cloud migrations to GCP and AWS, optimized GPU hosting to cut costs while reducing latency by 200ms, and architected core Kotlin/WebFlux services while holding full hiring authority. Previously at Replika, I maintained a custom Scala/Akka dialogue engine, integrated multi-provider billing services, and reduced CI/CD build runtimes by 3x using Python. My earlier experience includes building threat intelligence storage systems at BI.ZONE using Akka, Kafka, and HBase, as well as advancing from L2 support lead to a Python/Scala developer at Exante, where I built market data aggregation tools for quantitative research.

Experience

Product & Value Mindset
Leverages system design directly to drive business metrics—optimizing latency, user experience, and unit economics (achieved $k+ monthly infrastructure savings and a 200ms reduction in network latency).
Core Tech Stack
Expert in Kotlin (Spring WebFlux, Coroutines), Scala (Akka, Akka Cluster), Python (pytest), Distributed Systems, System Migrations (AWS, GCP, Firebase), Event-Driven Architecture (Kafka, Temporal), and Databases (PostgreSQL, MongoDB, Redis).
Cloud & Infrastructure Ownership
Experienced in managing cloud infrastructure end-to-end, writing Ansible automation playbooks, building resilient CI/CD pipelines, and navigating complex cross-organization migrations (including Apple ID OAuth transfers).
Engineering & Leadership Ownership
Proven track record as a hands-on technical leader, combining full hiring authority, candidates assessment, and architecture onboarding with active code contribution and cross-functional team execution.

Resume

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