Harun Sokullu — Backend Architect & Fintech Platform Leader • Fintech • Distributed Systems • Backend Architecture • Team Leadership
12+ years experience 12.8M+ users served

Harun Sokullu

Backend architect and engineering team lead specializing in regulation-grade fintech platforms and large-scale financial systems serving millions of users. He has more than 12 years of experience designing and leading high-availability, high-performance backend architectures for banking, fintech, and enterprise platforms.

His work includes mission-critical transaction processing systems, real-time data pipelines, microservices, distributed platforms, compliance-driven infrastructure, privacy-focused applications, and independently developed production systems.

Backend Architecture Fintech Platforms Distributed Systems Microservices High Availability Fault-Tolerant Systems Java & Spring Boot .NET Core TypeScript GraphQL Event-Driven Architecture Cloud & Kubernetes
harunsokullu@gmail.com harunsokullu.org GitHub LinkedIn

Professional Experience

Backend Team Lead · Superapp Backend

Ozan Elektronik Para — Türkiye, Remote
Aug 2023 – Present
  • Owns the architecture and delivery of a regulation-grade fintech backend platform powering a digital wallet used by more than 271,000 active users.
  • Leads a fully remote backend team and drives sprint planning, backlog prioritization, and cross-team execution for mission-critical payment and compliance systems.
  • Designed and evolved a fault-tolerant microservices architecture using Java, Spring Boot, and PostgreSQL.
  • Established platform-wide standards for scalability, security, reliability, and data consistency under high transaction volumes.
  • Acts as the technical interface between product, operations, and compliance teams.
  • Proactively manages technical debt, improves CI/CD practices, and removes delivery bottlenecks.

Senior Software Developer · Superapp Backoffice

Ozan Elektronik Para — Türkiye, Remote
Dec 2022 – Aug 2023
  • Architected a specialized Backend-for-Frontend layer using Nest.js and GraphQL for Ozan’s internal Backoffice.
  • Decoupled complex microservices from administrative interfaces and eliminated data over-fetching and performance bottlenecks.
  • Redesigned data-access patterns and query orchestration, reducing backoffice data-retrieval latency by approximately 50%.
  • Accelerated fraud investigation and compliance-review workflows while supporting auditability, traceability, and regulatory response requirements.
  • Established an architectural foundation used for scaling internal operational tools across the company.

Software Architect · Mobile Search & Chatbot

Akbank — Türkiye, Remote
Nov 2020 – Dec 2022
  • Led the backend architecture of Akbank’s customer-facing chatbot and mobile financial search platform serving more than 12.8 million users.
  • Designed and implemented a custom ETL and indexing pipeline that enabled users to search six months of account transactions and card-spending data.
  • Achieved an average search response time of approximately 50 milliseconds.
  • Engineered a near real-time ingestion system that made new transactions searchable within 15 minutes.
  • Implemented semantic financial search capabilities for intent-based transaction queries.
  • Architected high-throughput, highly available backend services under strict banking security and privacy requirements.
  • Contributed to technical hiring, architectural governance, and backend engineering quality standards.

Senior Software Specialist · D-Filo

Doğuş Teknoloji — Istanbul, Türkiye
Sep 2020 – Nov 2020
  • Co-designed the infrastructure and backend platform for a new fleet-management solution from the ground up.

Senior Software Specialist · VDF Filo

Doğuş Teknoloji — Istanbul, Türkiye
Apr 2016 – Sep 2020
  • Engineered core fleet-management modules for invoicing, operations, and collections using .NET Core and TypeScript.
  • Led DevOps initiatives for the project’s second phase, strengthening CI/CD pipelines and automating deployments.
  • Delivered continuous improvements supporting operational performance and platform reliability.

Software Specialist · NTV & NTV Spor

Doğuş Teknoloji — Istanbul, Türkiye
Sep 2018 – Dec 2018
  • Explored emerging technologies and NoSQL data stores while delivering media applications for NTV and NTV Spor.

Software Specialist · Doğuş İnşaat ERP

Doğuş Teknoloji — Istanbul, Türkiye
Jan 2018 – Sep 2018
  • Redesigned ERP interfaces and streamlined reporting workflows to improve data accuracy and usability.

Software Developer · LeasePlan ERP

Doğuş Teknoloji — Istanbul, Türkiye
Jul 2013 – Apr 2016
  • Delivered full-stack features for a vehicle fleet-rental ERP platform using .NET Framework, MSSQL, and JavaScript.

Education

Master of Science · Telecommunication Engineering

Istanbul Technical University — Istanbul, Türkiye
Sep 2011 – Jul 2013
  • Coursework completed.
  • GPA: 3.5 / 4.0.

Bachelor of Science · Telecommunication Engineering

Istanbul Technical University — Istanbul, Türkiye
Sep 2006 – Jul 2011
  • GPA: 3.45 / 4.0.
  • Graduated 7th in a class of 70.

Independent Production Systems

Swipd

App Store & Google Play
Jan 2026 – Present
  • Designed and developed a swipe-based affiliate shopping platform.
  • Built an AI-powered recommendation system using pgvector for personalized product suggestions.
  • Independently shipped a five-component system consisting of iOS, Android, backend, administration panel, and product crawler applications.
  • Used Swift, Kotlin, Fastify, Next.js, and Puppeteer.

WayOut

App Store
Dec 2025 – Present
  • Developed a cyberpunk-themed iOS digital wellbeing app that gamifies screen-time management.
  • Integrated Apple ScreenTime APIs including DeviceActivity, ManagedSettings, and FamilyControls.
  • Independently built a production-grade app with a shared SPM package architecture, four app extensions, StoreKit 2 subscriptions, Live Activities, and nine-language localization.
  • Implemented anti-cheat step validation, SwiftData persistence recovery, and cross-process extension communication through App Groups.

FixIt

Shopify App Store
Aug 2022 – Sep 2022
  • Designed and developed a B2B Shopify application that automates product-data optimization and sales recommendations.
  • The application is actively used by more than 250 online stores.
  • Built the system for stability, low-friction onboarding, scalable background processing, and commercial reliability.

Messagine Bot

Telegram Platform
Jan 2021 – Apr 2021
  • Designed and developed a privacy-first communication bot enabling secure and anonymous conversations.
  • Engineered custom message-routing and session-management architecture preserving user anonymity.
  • The platform reached 1,500 users and processed nearly 1,000 unique chat sessions.

Technical Expertise

  • .NET Core, TypeScript, Java, Spring Boot, Nest.js and GraphQL
  • Microservices and Backend-for-Frontend architecture
  • Distributed and fault-tolerant systems
  • PostgreSQL, MSSQL, NoSQL and Redis
  • RabbitMQ and event-driven architectures
  • Google Cloud Platform and Microsoft Azure
  • Docker, Kubernetes and CI/CD tooling
  • High-performance transaction processing
  • Real-time data pipelines and ETL systems
  • Fintech compliance, security and privacy-by-design

Leadership

  • Backend engineering team leadership
  • Technical mentorship and coaching
  • Sprint planning and backlog prioritization
  • Distributed-team coordination
  • Architectural governance
  • Technical hiring support
  • Product, operations and compliance collaboration
  • Stakeholder communication
  • Technical-debt and delivery-risk management