# Lazar Pejic > Co-Founder @ XSimulationLab | Computer Engineering Location: San Francisco Bay Area, United States Profile: https://flows.cv/lazar Senior Software Engineer with over a decade of experience in the software industry, specializing in high-performance, scalable, and distributed systems, machine learning, and deep learning. My expertise spans multiple domains, including financial software and gambling platforms, optimizing complex systems for high traffic and security. I have worked on telecom solutions for mobile operators, handling millions of daily active users, and video streaming platforms managing thousands of production servers. I have extensive experience in cloud orchestration across AWS, Azure, and GCP, as well as blockchain technologies, including the development of a node-as-a-service solution for Ethereum capable of processing billions of transactions. My work also includes building network security and monitoring tools to ensure system integrity and detect breaches. Additionally, I have contributed to SDK development for Azure Maps and implemented DevOps automation, optimizing infrastructure and CI/CD pipelines using Docker, Kubernetes, and Terraform. My technical expertise includes backend and systems development with Java, Golang, Python, Scala, Lua, and C++, along with experience in Linux kernel development and compilers. I have worked extensively with cloud and DevOps technologies, including AWS, Azure, GCP, Docker, Kubernetes, Terraform, and CI/CD automation. My database experience covers PostgreSQL, MongoDB, Cassandra, Elasticsearch, Redis, and TimescaleDB, while my messaging and event-driven systems knowledge includes Kafka and RabbitMQ. Additionally, I have experience in frontend development using Vue.js and Android development in Java and Kotlin. I hold a Bachelor's Degree in Electrical Engineering from the University of Belgrade – School of Electrical Engineering. My thesis, "Implementation of Actor Model and Its Application in Cloud Resource Management," focused on developing a framework for distributed systems based on the actor model, tested and verified using a simulated cloud environment with Python, Django, Docker, RabbitMQ, MariaDB, and Redis. ## Work Experience ### Co-Founder @ XSimulationLab Jan 2024 – Present | San Francisco Bay Area Our work centers on large-scale automation, deep-learning-driven simulations, and the development of custom tooling for advanced security and data analysis. • Built a GPU-accelerated simulation engine capable of modeling billions of interactions with deep learning–driven behavioral dynamics. • Designed and delivered end-to-end backend and frontend systems, including workflow automation, multi-account orchestration, and secure integrations with external services. Focused on on-prem and isolated deployments, reliability, and clean REST API design. • Architected and implemented distributed services using Docker and Kubernetes, including task runners, session-management components, isolated worker services, and VPN-based routing across separate network environments. • Implemented a Geo-IP routing service to direct users to the closest streaming nodes based on region and network conditions. • Worked on adaptive streaming pipelines (HLS/DASH), media-file encryption, and custom DRM integration for secure content delivery. • Developed Android and iOS app enabling field operators to capture and upload live video with geolocation, with the ability to search and browse content (live/time-shift/VoD) based on location. ### Senior Software Engineer Consulting @ Janea Systems Jan 2024 – Present ### Senior Software Engineer Contract @ Microsoft Jan 2024 – Jan 2025 Implemented new versions of the Azure Maps SDKs across C#, Java, Python, and JavaScript/TypeScript, covering multiple service areas such as Search, Routing, Rendering, Weather, and Time Zone APIs. Worked on redesigning core client libraries to align with the latest Azure SDK guidelines, improving API consistency, usability, performance, and metadata accuracy. ### Senior Software Engineer Contract @ Indeni (Acquired by BlueCat) Jan 2023 – Jan 2024 Implemented anomaly detection systems for network devices enabling time-series analysis and rule-based alerting using ML algorithms for clients such as Visa, United Airlines, etc. ### Senior Software Engineer @ Tenderly Jan 2023 – Jan 2024 Worked as part of the Gateway team at Tenderly (https://tenderly.co/), building a centralized, highly scalable Node-as-a-Service (NaaS) platform capable of handling billions of blockchain transactions across Ethereum and EVM-compatible networks. Focused on the design and development of backend services responsible for reliable node orchestration, transaction execution, state access, real-time tracing, and data delivery. Contributed to improving system performance, scalability, and fault tolerance in a distributed, microservices-based architecture. ### Senior Software Engineer @ Nutanix Jan 2020 – Jan 2023 Worked on Xi Frame (https://www.nutanix.com/products/frame), a cloud hosted Desktop as a Service platform. As a member of the Gateway team, I was responsible for building and maintaining a highly scalable backend system (based on actor model) that orchestrates machines and infrastructure across AWS, Azure, Google Cloud, and AHV. Focused on developing and optimizing core components for managing large pools of cloud machines: provisioning, terminating, starting/stopping instances, seamless instance type migrations, session-based server reservation, and publishing machine images. Designed and implemented a canary upgrade system for user servers, as well as a synchronization mechanism between Gateway and the internal payment/reporting pipeline. Delivered multiple performance optimizations and extended the functionality of the internal actor-based framework. Key technologies: Java, Python, Django, PostgreSQL, Zookeeper, Redis, RabbitMQ. ### Senior Software Engineer @ LotusFlare Jan 2018 – Jan 2020 Responsible for designing and implementing backend components for a large-scale mobile data management platform, including end-to-end Android/iOS application development. Worked primarily on server-side systems, including Nginx running Lua scripts, Java/Scala (Akka) daemons, and distributed services. Participated in the full lifecycle: architecture design, development, testing, deployment, and monitoring of services tightly integrated with mobile operators (charging, balance updates, OTP/SMS flows). Integrated with major telcos such as Indosat, Globe, and MTN Group. The platform served 10+ million daily active users. Designed and implemented the operator-specific API (OSA) framework and contributed to preventing multiple security vulnerabilities. Performed deep analysis of production data (Cassandra, ClickHouse), message flows (Kafka), and built Python tooling to fix data inconsistencies and automate internal operations. ### Software Engineer @ FIS Jan 2017 – Jan 2018 Optimized in-memory database performance for a high-volume post-trade processing system, improving throughput and reducing end-to-end latency. ## Education ### Bachelor of Engineering - BE in Computer Engineering University of Belgrade Jan 2014 – Jan 2018 ## Contact & Social - LinkedIn: https://linkedin.com/in/lazar-pejic-77a8502b7 --- Source: https://flows.cv/lazar JSON Resume: https://flows.cv/lazar/resume.json Last updated: 2026-03-22