Giovanni Mazza
Verified Expert in Engineering
MySQL Developer
London, United Kingdom
Toptal member since January 29, 2020
Gianni is a technical architect and AI systems engineer with 20+ years of experience across SaaS, edtech, ERP, and cloud platforms. He has led Rails monolith-to-microservice migrations, built AWS serverless architectures, delivered Toptal projects, and now leads the technical architecture of Skye, a voice-first AI tutor backed by a $2 million Gates Foundation research collaboration.
Portfolio
Experience
- MySQL - 20 years
- Ruby on Rails (RoR) - 18 years
- RSpec - 15 years
- Ruby - 15 years
- PostgreSQL - 6 years
- AWS Lambda - 3 years
- Amazon API Gateway - 3 years
- AWS Step Functions - 3 years
Preferred Environment
Docker, Bitbucket, GitHub, AWS Step Functions, Amazon API Gateway, AWS Lambda, Kubernetes, AWS Serverless Application Model (SAM), SDKs, Amazon CloudWatch
The most amazing...
...thing: I led the architecture of Skye, a voice-first AI tutor serving real pupils, backed by a $2 million Gates Foundation project with Stanford and Cornell.
Work Experience
Technical Architect | Back-end Lead
Thirdspacelearning LTD
- Implemented the back- and front-end pattern using the AWS API Gateway backed by AWS Step Functions to orchestrate Rails services.
- Implemented a tool to automatically generate architecture diagrams and documentation starting from the middleware layer, extending the CDK to generate documentation during the synthesis process.
- Fostered in the company the culture of well-architected cloud native applications following the principles of the 12 factors methodology.
Senior Full-stack Engineer
Alison Yeung
- Conducted a full architecture review to support fixing the prototype vs building from scratch the application.
- Managed the project entirely, setting up a Jira board and tracking the development process, and hitting the agreed-upon fixed timeline.
- Implemented the MVP according to the agreed architecture using the stack suggested by the client.
- Provided clear and extensive documentation, including ADRs covering every architectural decision, operational runbooks, and documentation for each section of the MVP.
- Provided a clear MVP to production path, including the migration from Vercel/Supabase to serverless AWS.
Senior Full-stack Engineer
Thirdspacelearning LTD
- Maintained a monolith Ruby on Rails app developed by a previous team in the last five years.
- Designed a tool to automate the developer to start working on the platform, cloning the repository, creating the database, importing a staging dump, setting up the developer environment, and checking the platform's status locally.
- Implemented several new features to keep the app up-to-date with the support team's requirements.
- Designed the new version of the edtech platform app to break the monolith into several different RoR API services (user management, bookings, sessions, reports, and contracts).
- Maintained the testing framework for the edtech platform; almost 100 new tests were added, and more than 200 tests were updated.
RoR Developer
Dan Halper
- Developed the back end of an app to manage real estate contracts to help people handle property buy and sell exchanges.
- Tracked and fixed bugs in the existing platform using Jira as a tracking tool.
- Implemented new features using the TDD methodology by implementing specs before the feature itself.
- Implemented the auto-generation and publication of the swagger file to help communicate efficiently with the front-end team.
Main Developer
Hgo Srl
- Designed and built, from scratch, the framework for both the back end (PHP) and the front end (jQuery) of a complete ERP system currently used by thousands of customers across Italy.
- Designed and built an ecosystem of microservices with Ruby on Rails to create a series of services related to the CMS and eCommerce.
- Designed and built the communication API with PHP for the ERP app for the new reactive front-end app.
- Supported the front-end team with the initial test of the new front end.
- Introduced the TDD methodology across the company.
- Introduced the Agile methodology across the company.
Experience
AI Maths Tutor
Brijio
https://github.com/redvex/brijioMy responsibilities included creating the server-side components: a WebSocket relay for managing browser connections and routing tool calls, and an MCP server offering functionalities like page reading, clicking, and form filling. The project also involved developing a shared protocol, health endpoints, structured logging, and an integration test suite.
Brijio was released as an npm package and a single Docker image. Technologies used included TypeScript, pnpm monorepo, per-request WebSocket connections, and default configurations for local development.
Thirdspacelearning (v2)
I chose AWS serverless technology to achieve our goal, and I implemented the BfF pattern with AWS API Gateway and the SAGA pattern using AWS Step Functions. The observability goal has been reached using Amazon CloudWatch to trigger alarms and notifications when an unhandled error happens.
Thirdspacelearning
Mathshub
https://mathshub.thirdspacelearning.comUnoERP
https://unoerp.itDoF Calculator and CameraDB
Resty
Subnotify
Rubric-based Agent Evaluation
The suite supports simulated tutoring scenarios, expected-response checks, and post-hoc scoring of real session logs across dimensions such as pedagogical appropriateness, responsiveness, safety, and rule adherence. Skye emits structured analytic events throughout each session, which are streamed through Fluent Bit into AWS Kinesis and processed by Lambda into the data warehouse. This allows the team to evaluate agent behavior at scale, monitor quality trends, and iterate quickly on tutoring rules as the AI system evolves.
My role covered the architecture, event model, evaluation strategy, AWS data pipeline integration, and the rubric-driven testing approach used to make AI tutor quality measurable and repeatable.
Education
Bachelor's Degree in Computer Science
Università degli studi di Catania - Catania, Sicily, Italy
Skills
Libraries/APIs
Node.js, jQuery, React, Ruby on Rails API, OpenAI API, REST APIs, Claude API, Google Maps, Pydantic, Vue
Tools
Git, RSpec, Postman, AWS Step Functions, Amazon CloudWatch, Structurizr, Claude, Claude Code, Amazon Elastic Container Service (ECS), ChatGPT, Claude Agent SDK, Bitbucket, Jira, GitHub, Figma, Auth0, Hotjar
Languages
PHP, Ruby, JavaScript, Regex, HTML, HTML5, TypeScript, SQL, CSS, SCSS, ECMAScript (ES6), Python, Swift
Frameworks
Ruby on Rails (RoR), LangGraph, Express.js, Agentic Frameworks, Prototype Framework, Sinatra, AWS Serverless Application Model (SAM), Next.js, Laravel
Paradigms
Agile Software Development, Microservices, Web App Design, Event-driven Architecture, Real-time Systems, Test-driven Development (TDD), Model Context Protocol (MCP), Automation, DevOps, Mobile Development, Search Engine Optimization (SEO), ETL, Testing, Test Automation, Serverless Architecture
Platforms
iOS, MacOS, Visual Studio Code (VS Code), AWS Lambda, Amazon Web Services (AWS), Amazon EC2, Docker, Linux, Kubernetes, Vercel, LangSmith, PostHog, Google Cloud Platform (GCP), RunPod
Storage
MySQL, SQLite, Amazon S3 (AWS S3), Amazon DynamoDB, Database Architecture, Database Management, PostgreSQL, Data Pipelines, Google Cloud
Other
Web Scraping, APIs, Amazon API Gateway, Prompt Engineering, LangChain, AI Agents, AI Integration, Full-stack, Architecture, AI Chatbots, Large Language Models (LLMs), Chatbots, Team Leadership, Artificial Intelligence (AI), Distributed Systems, Generative Artificial Intelligence (GenAI), Agentic AI, Full-stack Development, Software Architecture, Agentic AI Systems, Infrastructure, AI Systems, System Architecture, API Integration, Minimum Viable Product (MVP), Data Aggregation, Product Owner, Security, Browser Automation, Scraping, Data Scraping, Agentic RAG Systems, RAG Architecture, Retrieval-augmented Generation (RAG), Auditing, Documentation, Application Modernization, AI Agent Orchestration, AI Architecture, Data Privacy, AI Tools, Data Modeling, Vibe Coding, Scalability, Performance Optimization, Cloud, CRM, Customer Relationship Management (CRM), OpenAI, Web Crawlers, Anthropic, Cloud Infrastructure, CI/CD Pipelines, LLM Integration, Observability, AI-assisted Development, Infrastructure as Code (IaC), Orchestration, Software Engineering, Agentic Coding, API Design, LLM Agents, Startups, Early-stage Startups, Multi-tenant SaaS, SaaS, Multi-tenant Architecture, Analytics, Caching, Front-end, Third-party APIs, Third-party Integration, Conversational AI, Text Mining, SDKs, FastAPI, Supabase, Code Review, Code Auditing, Document Processing, Mobile Apps, Workflow Automation, Computer Vision, Dashboards, Data Visualization, Groq, AI Automation, Benchmarking, AI Evaluation, LLM Evaluation, Amazon Kinesis, Events, Rubric Design, AI Voice Agents, Real Estate
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