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Aris Tzollas
🇬🇷Greece
Created AtUpstaffer since April, 2025

Aris Tzollas — Senior Software Engineer

Expertise in Back-End Web, Full Stack Web.

Last verified on April, 2025

Core Skills

Bio Summary

Passionate Senior Software Engineer with 7 years of experience excels in building complex web applications leveraging mastery in languages such as JavaScript, TypeScript, C#, Go, and Python. Renowned for architecting a legal SaaS platform yielding a 40% operational efficiency boost and pioneering AI-powered chatbot integration, showcasing a 30% reduction in case handling efforts. Adept in cloud services (AWS, Azure, GCP), microservices, and CI/CD with an Agile mindset, drives collaboration and continuous improvement. Holds a solid foundation with a Bachelor's degree in Computer Science from NTUA, cementing technical prowess in the software industry through contributions to large-scale projects that enhance user experiences, performance, and reliability.

Technical Skills

Programming LanguagesGo, Java, PHP, Python, Ruby, TypeScript
JavaScript FrameworksAngular, Node.js, React, Vue.js
C++ Libraries and ToolsC/C++/C#
Java FrameworksSpring Boot
Databases & Management Systems / ORMMongoDB, MySQL, Neo4j, Redis
Cloud Platforms, Services & ComputingGCP
Deployment, CI/CD & AdministrationAnsible, Jenkins
QA, Test Automation, SecurityCypress, Selenium
Version ControlGithub Actions
SDK / API and IntegrationsGraphQL, JWT, OAuth, RESTful API
Mail / Network Protocols / Data transferGRPC, JWT, WebSockets
Message/Queue/Task BrokersKafka, RabbitMQ
Virtualization, Containers and OrchestrationTerraform

Work Experience

Senior Software Engineer, Law Practice AI

Duration: SEP 2023 - Current
Summary: Architected a legal SaaS platform, engineered an event-driven microservice architecture, developed an AI-powered chatbot, optimized database performance, led the migration of a monolithic service to microservices, deployed multi-tenant cloud infrastructure, integrated a document classification system, designed RESTful APIs, enhanced security, automated deployment workflows, managed API Gateway integrations, implemented observability practices, and developed automated testing suites.
Responsibilities: Core contributor to architecting and developing the platform, optimizing performance, ensuring high availability, scalability, and security, and leading migrations and deployments.
Technologies: ASP.NET Core, Node.js, WebSocket, PostgreSQL, RabbitMQ, Azure Cognitive Services, Azure Kubernetes Service, OAuth 2.0, JWT, Azure Active Directory, GitHub Actions, Kong, Grafana, ELK Stack, Selenium, Cypress

Full Stack Developer, Discord Inc.

Duration: JUL 2022 - MAR 2023
Summary:
  • Developed backend services for Discord to support millions of users, migrated RESTful APIs to gRPC, designed a high-performance caching system, built a Neo4j-based social graph, integrated OAuth 2
  • 0, implemented real-time event streaming, collaborated on data processing pipelines, automated data processing workflows, enhanced user engagement with new frontend features
Responsibilities: Involved in backend development, API migration and optimization, database and caching solution design, real-time event handling, data processing enhancements, and frontend feature development.
Technologies: Node.js, Go, Redis, Neo4j, OAuth 2.0, Apache Kafka, AWS S3, DynamoDB, Python, React

Senior Backend Developer, In-House Projects

Duration: FEB 2020 - MAY 2022
Summary: Designed a real-time monitoring and alerting system, developed a job scheduling system, implemented Kubernetes-based autoscaling, maintained a CI/CD pipeline, built RESTful APIs, optimized cloud costs through serverless migrations, enhanced multi-cloud compatibility, secured data pipelines, built distributed caching mechanisms, integrated RBAC, developed a data pipeline, led the migration to a microservices architecture, designed and optimized databases, implemented observability practices, and developed automated test suites.
Responsibilities: Handled backend software design, development and optimization, CI/CD pipeline maintenance, cloud resource management and cost optimization, data security and encryption, microservices migration and database optimization.
Technologies: Kafka, Redis, Golang, Horizontal Pod Autoscaler, Cluster Autoscaler, Jenkins, GitHub Actions, ArgoCD, Java Spring Boot, Azure Functions, AWS Lambda, Terraform, Ansible, Azure Key Vault, AWS KMS, Redis, Memcached, Apache Spark, Delta Lake, Python, Node.js, .NET, MongoDB, Cassandra, DynamoDB, MySQL, Prometheus, Grafana, ELK Stack, xUnit, NUnit, PyTest, Mocha, Jest

Junior Software Engineer, Various Web Applications

Duration: SEP 2018 - JAN 2020
Summary: Developed full-stack web applications, built a real-time customer feedback system, integrated payment gateways, contributed to logistics tracking system development, implemented RESTful APIs, and participated in database migrations and optimizations.
Responsibilities: Focused on full-stack application development, payment integration, logistics tracking systems, API development, and database migrations.
Technologies: PHP, Java, AngularJS, Stripe, PayPal, RESTful APIs, MySQL, PostgreSQL

Education

  • Bachelor’s degree in Computer Science
    Sep 2014 - May 2018

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