Aris Tzollas — Senior Software Engineer

Expertise in Full Stack Web, Back-End Web.

Last verified on March, 2026

Core Skills

NestJS

1 yr.

3 yr.

Bio Summary

Software engineer with 7+ years of experience specializing in full-stack development using JavaScript/TypeScript, C#, Go, and Python across macOS, Unix, and Linux environments.
Proven expertise in architecting scalable microservices, event-driven systems, and cloud-native applications leveraging AWS, Azure, GCP, Kubernetes, Docker, and CI/CD pipelines.
Strong background in designing and optimizing databases (PostgreSQL, MongoDB, Cassandra, Neo4j) and implementing high-performance caching and real-time data streaming solutions with Kafka and Redis.
Skilled in modern frameworks and tools including Node.js, Nest.js, React, Django, and Spring, with hands-on experience in OAuth 2.0, JWT security, and compliance with ISO 27001 and GDPR.
Computer Science degree with demonstrated success in improving system performance by up to 40%, automating workflows, and leading migrations from monolithic to microservices architectures.

Technical Skills

Programming Languages	Go, Java, JavaScript, Kotlin, PHP, Ruby, TypeScript
JavaScript Frameworks	Angular, Express, Ext JS, NestJS, Node.js, Nuxt, React, Vue.js
.NET Platform	ASP.NET Core Framework, ASP.NET MVC, Azure
AI & Machine Learning	AWS Textract, OCR, OpenAI
Go Frameworks	Beego, Gin
Go Libraries and Tools	Beego, Gin
C++ Libraries and Tools	C/C++/C#
Mobile Frameworks and Libraries	Crashlytics
Python Frameworks	Django REST framework, FastAPI, Flask
Android Libraries and Tools	Kotlin
Python Libraries and Tools	pytest
Java Frameworks	Spring, Struts 2
Security	RBAC
Databases & Management Systems / ORM	AWS DynamoDB, Cassandra, Memcached, MongoDB, MySQL, Neo4j, PostgreSQL, Redis, SQLAlchemy
Cloud Platforms, Services & Computing	Azure, GCP
Amazon Web Services	AWS Auto Scaling, AWS Cognito, AWS DynamoDB, AWS Kinesis, AWS KMS, AWS Lambda, AWS Textract
Azure Cloud Services	Azure Key Vault
Google Cloud Platform	Cloud Functions
Methodologies, Paradigms and Patterns	Agile
Deployment, CI/CD & Administration	Ansible, ArgoCD, Blazor, CI/CD, GitLab CI, Helm Charts, Jenkins
Version Control	BitBucket, Github Actions
QA, Test Automation, Security	Cypress, Jest, Mocha, NUnit, pytest, Selenium, xunit
SDK / API and Integrations	FastAPI, GraphQL, JWT, OAuth, PayPal API, RESTful API, Stripe
Mail / Network Protocols / Data transfer	GRPC, JWT, WebSockets
Message/Queue/Task Brokers	Kafka, RabbitMQ
Logging and Monitoring	Prometheus
Virtualization, Containers and Orchestration	Terraform
Other Technical Skills	Delta lake

Work Experience

Senior Software Engineer - Practice AI (Legal SaaS Platform Development)

Duration: SEP 2023 - Current
Summary: Development of a legal SaaS platform to streamline document management and case workflows for legal professionals, enhancing operational efficiency and data reliability through modern microservices and AI-powered tools.
Responsibilities:

Architected the platform using Node.js, Nest.js, WebSocket, and PostgreSQL.
Engineered event-driven microservice architecture with RabbitMQ.
Developed AI-powered chatbot for document assistance using LangChain, GPT-4, and AWS Bedrock.
Optimized database performance and led backend migration from Ruby monolith to Node.js microservices.
Managed multi-tenant cloud infrastructure on Amazon EKS with Helm charts.
Integrated document classification with OCR and OpenAI GPT APIs.
Designed and built RESTful APIs with Express.js and NestJS.
Implemented security measures including OAuth 2.0, JWT, and Amazon Cognito.
Automated deployment workflows with GitHub Actions and managed API Gateway integrations.
Implemented observability with Prometheus and Grafana and developed automated testing suites.

Technologies: Node.js, Nest.js, WebSocket, PostgreSQL, RabbitMQ, LangChain, GPT-4, AWS Bedrock, SQLAlchemy, Ruby, Amazon EKS, Helm, OCR, AWS Textract, OpenAI GPT APIs, Express.js, OAuth 2.0, JWT, Amazon Cognito, GitHub Actions, Amazon API Gateway, Prometheus, Grafana, Selenium, Cypress

Full Stack Developer - Discord Inc. (Backend Services and Real-Time Features for Discord)

Duration: JUL 2022 - MAR 2023
Summary: Development and optimization of backend services and real-time features to support millions of active users on Discord, focusing on performance, scalability, and enhanced user engagement.
Responsibilities:

Developed backend services using Node.js and Go.
Migrated RESTful APIs to gRPC.
Designed high-performance caching system with Redis.
Built Neo4j-based social graph database for user relationship modeling.
Integrated third-party authentication systems including OAuth 2.0.
Implemented real-time event streaming with Apache Kafka.
Collaborated on data processing pipeline using AWS S3, DynamoDB, and Python.
Automated backend data workflows integrating machine learning models.
Enhanced frontend with React for real-time messaging and notifications.

Technologies: Node.js, Go, gRPC, Redis, Neo4j, OAuth 2.0, Apache Kafka, AWS S3, DynamoDB, Python, React

Senior Backend Developer - VXG Inc. (Real-Time Monitoring and Microservices Architecture for VXG Inc.)

Duration: FEB 2020 - MAY 2022
Summary: Development of real-time monitoring, alerting, and job orchestration systems, migration to microservices architecture, and optimization of cloud infrastructure for scalable distributed applications in logistics and finance sectors.
Responsibilities:

Designed real-time monitoring and alerting system using Kafka and Redis Streams.
Developed job scheduling and orchestration system with Golang.
Implemented Kubernetes autoscaling with HPA and Cluster Autoscaler.
Maintained CI/CD pipelines with Jenkins, GitHub Actions, and ArgoCD.
Built and maintained RESTful APIs with Java Spring Boot.
Optimized cloud costs by migrating workloads to Azure Functions and AWS Lambda.
Automated infrastructure provisioning with Terraform and Ansible.
Secured data pipelines with Azure Key Vault and AWS KMS.
Built distributed caching with Redis and Memcached.
Integrated RBAC using Kubernetes service accounts and Azure IAM policies.
Developed high-throughput data pipeline with Apache Spark, Kafka, and Delta Lake.
Led migration from monolithic to microservices architecture using Python, Node.js, and .NET.
Designed and optimized NoSQL and SQL databases including MongoDB, Cassandra, DynamoDB, and MySQL.
Implemented observability with Grafana and ELK Stack.
Developed automated test suites with xUnit, NUnit, PyTest, Mocha, and Jest.

Technologies: Kafka, Redis Streams, Golang, Kubernetes, HPA, Cluster Autoscaler, Jenkins, GitHub Actions, ArgoCD, Java Spring Boot, Azure Functions, AWS Lambda, Terraform, Ansible, Azure Key Vault, AWS KMS, Redis, Memcached, Kubernetes RBAC, Azure IAM, Apache Spark, Delta Lake, Python, Node.js, .NET, MongoDB, Cassandra, DynamoDB, MySQL, Grafana, ELK Stack, xUnit, NUnit, PyTest, Mocha, Jest

Junior Software Engineer - Appnox Technologies (Full-Stack Web Applications and Systems Development)

Duration: JUN 2018 - JAN 2020
Summary: Development and deployment of full-stack web applications including customer feedback systems, payment gateway integrations, and logistics tracking systems to improve user engagement and operational efficiency.
Responsibilities:

Developed full-stack web applications using PHP and Java in Agile environment.
Built real-time customer feedback system with PHP and AngularJS.
Integrated payment gateways such as Stripe and PayPal.
Contributed to logistics tracking system with third-party API integrations.
Developed RESTful APIs in PHP for external service integration.
Participated in database migration from MySQL to PostgreSQL with indexing and partitioning.

Technologies: PHP, Java, AngularJS, Stripe, PayPal, MySQL, PostgreSQL

Education

Sunway University
Bachelor’s degree in Computer Science
Sep 2012 - May 2017

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