Giovanni Mazza, Developer in London, United Kingdom
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Giovanni Mazza

Bio

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

Thirdspacelearning LTD
Amazon API Gateway, APIs, Amazon CloudWatch, SDKs, Agile Software Development...
Alison Yeung
JavaScript, API Integration, SDKs, TypeScript, ETL, PostgreSQL, React...
Thirdspacelearning LTD
Docker, PostgreSQL, Node.js, Sinatra, Ruby on Rails (RoR), Ruby, MySQL, SDKs...

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

2022 - PRESENT
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.
Technologies: Amazon API Gateway, APIs, Amazon CloudWatch, SDKs, Agile Software Development, AWS Lambda, AWS Step Functions, AWS Serverless Application Model (SAM), Git, GitHub, Ruby on Rails (RoR), Prompt Engineering, AI Agents, AI Integration, Full-stack, Amazon S3 (AWS S3), Amazon Web Services (AWS), FastAPI, Architecture, AI Chatbots, Chatbots, Team Leadership, Microservices, Artificial Intelligence (AI), Distributed Systems, Generative Artificial Intelligence (GenAI), Agentic AI, Software Architecture, Agentic AI Systems, Infrastructure, AI Systems, System Architecture, API Integration, Data Aggregation, Product Owner, Code Review, Code Auditing, Security, Amazon DynamoDB, Data Pipelines, Agentic RAG Systems, Figma, RAG Architecture, Retrieval-augmented Generation (RAG), Auditing, REST APIs, Documentation, Auth0, Express.js, Database Architecture, SQL, Data Privacy

Senior Full-stack Engineer

2026 - 2026
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.
Technologies: JavaScript, API Integration, SDKs, TypeScript, ETL, PostgreSQL, React, Large Language Models (LLMs), Artificial Intelligence (AI), Supabase, Jira, PostHog, Hotjar, Vercel, Minimum Viable Product (MVP), Data Aggregation, Product Owner, Code Review, Auditing, REST APIs, Documentation, Application Modernization, Database Architecture, SQL, Data Privacy

Senior Full-stack Engineer

2019 - 2022
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.
Technologies: Docker, PostgreSQL, Node.js, Sinatra, Ruby on Rails (RoR), Ruby, MySQL, SDKs, Amazon API Gateway, AWS Step Functions, AWS Lambda, AWS Serverless Application Model (SAM), Kubernetes, TypeScript, RSpec, Structurizr, Regex, Git, Ruby on Rails API, GitHub, React, Agile Software Development, Postman, SCSS, ECMAScript (ES6), HTML, Visual Studio Code (VS Code), Test-driven Development (TDD), MacOS, Linux, Full-stack, Amazon S3 (AWS S3), Amazon Web Services (AWS), Team Leadership, Microservices, Distributed Systems, Full-stack Development, System Architecture, API Integration, Product Owner, Code Review, Figma, RAG Architecture, Retrieval-augmented Generation (RAG), Auditing, REST APIs, Documentation, Application Modernization, Database Architecture, SQL, Data Privacy

RoR Developer

2020 - 2021
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.
Technologies: Ruby on Rails (RoR), Jira, Regex, MySQL, Ruby, Git, Ruby on Rails API, SCSS, ECMAScript (ES6), HTML, Visual Studio Code (VS Code), Test-driven Development (TDD), MacOS, Linux, Full-stack, API Integration, Product Owner, Code Review, Figma, REST APIs, Documentation, Database Architecture, SQL, Data Privacy

Main Developer

2006 - 2019
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.
Technologies: Vue, jQuery, Prototype Framework, JavaScript, Ruby on Rails (RoR), Ruby, PHP, Web Scraping, MySQL, Regex, Git, Ruby on Rails API, CSS, Agile Software Development, ECMAScript (ES6), HTML, Visual Studio Code (VS Code), MacOS, Linux, Full-stack, API Integration, Product Owner, Google Maps, Code Review, SQL, Data Privacy

Experience

AI Maths Tutor

I’ve been the architect and the lead developer of Skye, a voice-to-voice agent used by thousands of pupils in the UK and the US. The agent replaced human tutors as the company's tutoring provider, allowing it to revolutionize the tuition market and position itself as a leader in the new AI-first tuition market. The project is backed by the Gates Foundation in collaboration with Stanford and Cornell University.

Brijio

https://github.com/redvex/brijio
I designed and developed Brijio, enabling AI agents to use your native browser via Safari or Chrome extensions, accessing your live session with cookies, logins, and more. This eliminates CAPTCHA challenges and bot detection barriers.

My 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)

As a technical architect, I've been tasked to re-architect the old platform to improve scalability, reliability, and observability.

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

An intervention program software that helps pupils boost their KS2, SATs, and GCSE performance with the help of real tutors across the word. The platform manages tutors' contracts, students' assessments, teachers' planning sessions, and admin operations.

Mathshub

https://mathshub.thirdspacelearning.com
A math resource hub for maths to help teachers to improve their lessons. The CMS organizes and correlates resources, and the API serves millions of requests using an efficient caching mechanism to reduce the load on the database.

UnoERP

https://unoerp.it
An ERP system to help small/medium-sized company to manage their business. The software manages resources, accounting, warehouse, tasks, tickets, etc. As a sole developer, I built the framework and most of the modules for the ERP system.

DoF Calculator and CameraDB

iOS app to calculate the depth of field (DoF). The app scraps data from the web to build a database of cameras and lenses to help the user carefully calculate the DoF without knowing the spec of the camera or the lens. The app searches, for example, images taken with the same camera and the same lens via Flickr API.

Resty

A microservices ecosystem built to set up CMS, eCommerce, newsletter, and other services by activating just the services the customers need. The ecosystem was coordinated by a centralized house-made orchestrator.

Subnotify

The Subnotify app indexes the followed TV shows and gets a notification on iOS devices when a new subtitle is available. The app implemented a few smart features to match user preferences with TV shows, maintaining a database of TV shows, episodes, and actors to suggest new releases to users actively.

Rubric-based Agent Evaluation

I designed and implemented an event-based evaluation suite for Skye, Third Space Learning’s AI voice tutor, used in real classroom sessions. The system validates AI tutor behavior against editable pedagogical rubrics, combining synthetic scenario tests with production trace 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

2000 - 2006

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, Google Maps, Vue

Tools

Git, RSpec, Postman, AWS Step Functions, Amazon CloudWatch, Structurizr, Claude, Claude Code, 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), Express.js, Prototype Framework, Sinatra, AWS Serverless Application Model (SAM), Next.js, Laravel, LangGraph

Paradigms

Agile Software Development, Microservices, Web App Design, Event-driven Architecture, Test-driven Development (TDD), Model Context Protocol (MCP), ETL, Testing, Test Automation, Serverless Architecture

Platforms

iOS, MacOS, Visual Studio Code (VS Code), AWS Lambda, Amazon Web Services (AWS), Docker, Linux, Kubernetes, Vercel, LangSmith, PostHog

Storage

MySQL, SQLite, Amazon S3 (AWS S3), Amazon DynamoDB, Database Architecture, PostgreSQL, Data Pipelines

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, Text Mining, SDKs, FastAPI, Supabase, Code Review, Code Auditing, Document Processing, Mobile Apps, Groq, AI Automation, Benchmarking, AI Evaluation, LLM Evaluation, Amazon Kinesis, Events, Rubric Design, AI Voice Agents

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