Marco is available for hire
Hire MarcoMarco Martins Castanho
Verified Expert in Engineering
Scrum Master and Software Developer
Lisbon, Portugal
Toptal member since June 11, 2021
Bio
Marco is a software engineer with nine years of experience in IT, focusing on both back-end and front-end development. After graduating with an MSc in electrical engineering and computer science, he worked as an IT consultant in Lisbon, Portugal. He accepted the challenge of moving to France to gather experience working in international contexts. Since then, Marco has worked as a software engineer, technical lead, and scrum master on various projects.
Portfolio
SayNode Operations AG
Back-end, Python, Django, Django REST Framework, Pytest, REST, GitHub Actions...
The New York Academy of Sciences
Python, Django, React, Back-end, Front-end, JavaScript, TypeScript...
Nova Technology Canada Inc.
Technical Leadership, React, Amazon Web Services (AWS), Django, Python, Fintech...
Experience
- Back-end - 11 years
- Python - 8 years
- JavaScript - 7 years
- TypeScript - 5 years
- Django - 5 years
- Node.js - 5 years
- React - 5 years
- Django REST Framework - 4 years
Work Experience
Head of Back-end | Project Lead
2024 - PRESENT
SayNode Operations AG
- Implemented the integration test suite for Django/DRF projects without test coverage.
- Introduced Django best practices through code refactoring and writing guidelines.
- Oversaw the progress and status of the development of features on back- and front-end components.
- Refined and estimated new features requested by the client, which meant analyzing and understanding the requirements, clearing areas of uncertainty, and planning the technical implementation.
- Increased the test coverage of the largest project from 0 to 90%.
Technologies: Back-end, Python, Django, Django REST Framework, Pytest, REST, GitHub Actions, Back-end Development, API Development, Amazon Web Services (AWS), OpenAPI, WebSockets, Celery, Web3, RESTFul APIs, Agile Software Development, API Design
Lead Engineer (via Toptal)
2021 - 2025
The New York Academy of Sciences
- Fixed pre-existing issues that were causing malfunctions in core features, bringing the innovation and collaboration platform to a stable state.
- Upgraded the main frameworks using modern versions of Django, React, and Python. Upgraded many of the project's dependencies and libraries to current versions or replaced them with alternatives.
- Migrated the extended JavaScript front-end code to smaller and modular TypeScript components, with stricter type and data validations for cleaner and more error-proof code. Enabled linting for code quality automated validations.
- Refactored the front-end code generally by modernizing it to the current best practice standards, cleaning previously poorly maintained legacy code, organizing the file structure, and creating modular, reusable functional components.
- Improved back-end test coverage considerably by implementing a large set of tests for the REST endpoints of the project's main features. Added an automatic test coverage report to keep track of the coverage percentage and covered code.
- Redesigned a few front-end pages and reusable UI components, improving the UI and UX. Re-implemented the application's internal messaging feature and designed the new UI and UX.
- Improved the security of the REST APIs for data access in the back end by setting authentication, endpoint, and object-specific permission rules.
- Implemented new automated background tasks to help the program administrators manage users, send bulk emails to target users, and generate usage reports.
- Added functionalities to the project's main feature—Team Projects—such as setting milestones, inviting others to join the team, and changing the team leader. Fixed or implemented automatic validation and enforcement of business rules.
- Investigated, fixed, tested, and deployed solutions to issues. Helped program managers identify areas for improvement. Designed and implemented solutions from a technical, functional, UI, and UX standpoint.
Technologies: Python, Django, React, Back-end, Front-end, JavaScript, TypeScript, Django REST Framework, REST APIs, Web Development, CSS, SCSS, HTML, Scripting, Celery, Full-stack, MySQL, Unit Testing, Front-end Development, Ansible, Amazon Web Services (AWS), Node.js, React Router, React Navigation, Sentry, Full-stack Development, Django ORM, Object-relational Mapping (ORM), Code Refactoring, Back-end Development, API Development, API Design
Tech Lead
2023 - 2023
Nova Technology Canada Inc.
- Designed a solution architecture based on the client's requirements.
- Estimated the effort to implement the designed solution.
- Implemented features on both the back and front ends.
- Interviewed and hired the people who would be the technical team members.
- Implemented the base skeleton for the Django back end.
Technologies: Technical Leadership, React, Amazon Web Services (AWS), Django, Python, Fintech, Full-stack, TypeScript, React Redux, Node.js, Software Architecture, Business Analysis, Technical Requirements, Team Leadership, Remote Team Leadership, Cross-functional Team Leadership, Full-stack Development, Django ORM, Code Review
Technical Lead and Scrum Master
2021 - 2021
ALTEN Group
- Developed an application for a client's project that allows maintenance operators to configure and maintain electrical closets.
- Implemented the back end that interacted with the system to get data from the electrical system and applied the changes.
- Assisted in implementing the web application the operators use to interact with the system.
- Collaborated with the client, a European multinational company providing energy and digital automation solutions for efficiency and sustainability.
Technologies: Agile, Git, JavaScript, TypeScript, Node.js, NestJS, React, SQLite, NATS, Protobuf, JSON Web Tokens (JWT), REST, Jest, GitLab, GitLab CI/CD, SQL, WebSockets, Back-end, APIs, Unit Testing, RPC, gRPC, Front-end, Front-end Development, Technical Leadership, TypeORM, Full-stack, Team Leadership, Object-relational Mapping (ORM), Code Review
Technical Lead
2020 - 2021
ALTEN Group
- Managed the handover of a client's web application maintenance project from the previous contracting company.
- Tracked and fixed bugs on the Python back end and the Angular front end.
- Studied solutions and sized the cost of improvements in the project requested by the client.
- Trained new trainees to understand the project and implement requested changes fully.
- Worked with the client, a French global sporting goods retailer.
Technologies: Python, Google Cloud Platform (GCP), Python 2, Shell, Bash, Bash Script, Bower, Google Cloud, Git, Back-end, Front-end, Angular, Front-end Development, Technical Leadership
Software Engineer
2020 - 2020
ALTEN Group
- Developed a mobile application for money transactions.
- Implemented new screens for the application, both user interface and functionalities.
- Proposed improvements on both UI and UX to the design team.
Technologies: React Native, Node.js, TypeScript, JavaScript, Git, GitLab, REST, Mobile, Mobile Development, Cross-platform, Digital Payments, Mobile Banking
Software Engineer
2020 - 2020
ALTEN Group
- Developed a Node.js application for internal use of the company to help project managers manage clients' projects.
- Implemented new features on the NestJS back end to plot a project's burndown chart.
- Improved the project's unit test coverage by writing unit tests for new and existing features.
Technologies: TypeScript, JavaScript, Node.js, NestJS, MongoDB, Jest, REST, REST APIs, Jira, Jira REST API, Git, GitLab, NoSQL, Back-end, Docker, Docker Compose, APIs, Unit Testing, Architecture, Express.js, MERN Stack, Code Review
Technical Lead
2020 - 2020
ALTEN Group
- Studied the request for proposals from a potential client to apply for a client project regarding automation of login in multiple applications running in cars infotainment systems.
- Studied possible solutions to implement the automated login in Android systems.
- Wrote a report detailing the technical solution presented to the potential client as part of the technical and financial proposition.
- Worked with the client, a French global automotive supplier of car audio, automotive navigation systems, and visual and communication equipment.
Technologies: Android, Web Security
Software Engineer
2018 - 2020
Amadeus
- Maintained an application's back-end nodes in Python and C++ to book train tickets in multiple providers.
- Implemented new back-end nodes in Python for storing data in MongoDB and made them accessible through a REST API.
- Performed a functional and technical analysis of new features to be implemented in the Python back ends.
Technologies: Agile, Scrum, Python, REST, SQL, MongoDB, JSON, Test-driven Development (TDD), C++, Git, Jira, Confluence, Bitbucket, Bash Script, NoSQL, Python 2, Python 3, Back-end, Flask, REST APIs, Python API, SOAP, XML, Unit Testing, Architecture, JavaScript, Technical Leadership, Testing, Code Review, Code Refactoring, Flask API
Test Automation Engineer
2016 - 2018
Celfocus
- Implemented scripts to automate the Session Initiation Protocol (SIP) application server testing, focusing on load testing.
- Executed performance tests on the SIP server and wrote performance test reports.
- Maintained the testing environments for automated and functional testing teams, such as managing the state of environments, installing and migrating new releases, and managing database seeding.
- Created tools to help the functional testing team automate configuration processes.
Technologies: C++, Microsoft SQL Server, Java, Session Initiation Protocol (SIP), Python, Ruby, Git, Shell, Bash, Bash Script, SQL, Python 3, PostgreSQL, Scraping, Testing, Selenium
Junior Developer
2015 - 2016
Celfocus
- Maintained a web portal that allows users to configure their preferences for using an enterprise phone system.
- Maintained SOAP and REST services on an Oracle Service Bus—services consumed by the web portal.
- Implemented a REST API in Java and migrated the services from OSB to this new server.
Technologies: JavaScript, SOAP, REST, Oracle Service Bus (OSB), Java, REST APIs, Git, GitLab, Back-end, Front-end
Junior Developer
2014 - 2015
Celfocus
- Implemented a new feature on a C++ SIP application server that manages the establishment of phone calls, which impacted many other features.
- Tracked, analyzed, and fixed issues using HP Quality Center and Application Lifecycle Management (ALM) tool.
- Implemented scripts to help in the testing of new features or bug fixes.
Technologies: C++, PostgreSQL, Session Initiation Protocol (SIP), Boost, Shell, Bash, Bash Script, Back-end
Project History
Smarteam: An App to Manage Sports Games with Friends
https://github.com/marcomartinscastanho/SmarteamAn Android application for managing sports games with friends, keeping track of results, and obtaining a balanced distribution of teams. My idea was based on the need to have balanced teams when I played soccer regularly with friends. I developed the application while learning Android.
Cooking Recipes Manager
https://github.com/marcomartinscastanho/Secret-IngredientA React-based web application that allows storing, managing, viewing, and printing recipes. This training project uses Firebase back end with a React/TypeScript front end. I developed the entire React application.
The project is ongoing.
The project is ongoing.
Twitter Image Scraper
https://github.com/marcomartinscastanho/twitter-image-scraperThis project consists of three parts:
• a Google Chrome extension that scrapes images from an open Twitter tab and saves them to a gallery.
• a Django back-end that manages the image gallery.
• a React front-end that displays the image gallery.
It was developed as a way to practice and learn a set of useful skills.
• a Google Chrome extension that scrapes images from an open Twitter tab and saves them to a gallery.
• a Django back-end that manages the image gallery.
• a React front-end that displays the image gallery.
It was developed as a way to practice and learn a set of useful skills.
CREUA Movie Sessions
https://github.com/marcomartinscastanho/creua-movie-sessionsA React web app to randomly select a movie director from a list and present their filmography. The list is maintained in a Google spreadsheet read by the application through Google API. The app also stores the record of selected movie directors on Firebase to prevent the same director from being selected twice in a row.
CookAI
https://github.com/marcomartinscastanho/CookAIBuilt a Next.js web application integrating OpenAI API to generate cooking recipes using artificial intelligence. Also, I implemented user authentication to enable users to save recipes in their profiles.
Criterion Challenge
A Django web application to auto-select movies to watch based on a 52-category plan for the year, with customizable criteria and preferences. I designed, implemented, and tested the application, which was written entirely in Django (back and front end) and deployed on the free tier of Render.
Education
2007 - 2014
Master's Degree in Electrical Engineering
Instituto Superior Técnico - Lisbon, Portugal
Certifications
MAY 2026 - PRESENT
Software Architecture & System Design Practical Case Studies
Udemy
JULY 2024 - PRESENT
GitLab CI/CD: Pipelines, CI/CD and DevOps for Beginners
Udemy
FEBRUARY 2024 - PRESENT
GraphQL by Example
Udemy
FEBRUARY 2024 - PRESENT
NextJS & OpenAI - 2024 Edition
Udemy
SEPTEMBER 2020 - PRESENT
Build a Back-end REST API with Python and Django | Advanced
Udemy
AUGUST 2020 - PRESENT
Django 3 | Full-stack Websites with Python Web Development
Udemy
MAY 2020 - PRESENT
The Complete 2020 Flutter Development Bootcamp with Dart
Udemy
APRIL 2020 - PRESENT
The Complete Android Oreo Developer Course
Udemy
FEBRUARY 2020 - PRESENT
The Complete Regular Expressions Course For Beginners
Udemy
FEBRUARY 2020 - PRESENT
Professional Scrum Master I
Scrum.org
FEBRUARY 2020 - PRESENT
Business Analysis Fundamentals
Udemy
SEPTEMBER 2019 - PRESENT
Complete Python Bootcamp: Go From Zero to Hero in Python 3
Udemy
FEBRUARY 2019 - PRESENT
Git and Bitbucket
Amadeus
Skills
Libraries/APIs
REST APIs, Node.js, React, API Development, Flask API, Protobuf, Jira REST API, Python API, React Redux, Redux-Saga, React Router, React Navigation, React Query, Django ORM, OpenAPI
Tools
Git, Jira, GitLab, Bitbucket, Shell, GitLab CI/CD, Confluence, Bower, Docker Compose, Celery, Ansible, Sentry, Prisma, ChatGPT, Pytest
Languages
Python, TypeScript, Python 3, SQL, JavaScript, HTML, C, Java, C++, Ruby, Dart, Regex, Bash, Bash Script, Python 2, XML, CSS, SCSS, GraphQL, Sass
Frameworks
Django, Django REST Framework, NestJS, JSON Web Tokens (JWT), Flask, Express.js, Jest, React Native, Flutter, Bootstrap, Boost, gRPC, Redux, Chrome, Angular, Next.js, Tailwind CSS, Selenium
Paradigms
REST, Scrum, Test-driven Development (TDD), RESTful Development, Code Refactoring, Agile, Design Patterns, Microservices, Unit Testing, Mobile Development, Cross-platform, Testing, Object-relational Mapping (ORM), DevOps, Agile Software Development
Storage
JSON, SQLite, PostgreSQL, MongoDB, NoSQL, Microsoft SQL Server, Google Cloud, MySQL
Platforms
Visual Studio Code (VS Code), Android, Google Cloud Platform (GCP), Firebase, Windows, Mobile, Docker, MacOS, Unix, Netlify, Amazon Web Services (AWS), Vercel, AWS Elastic Beanstalk
Other
Back-end, Scrum Master, Front-end, Front-end Development, Full-stack Development, Code Review, Back-end Development, Session Initiation Protocol (SIP), SOAP, Oracle Service Bus (OSB), NATS, IT Business Analysis, Business Analysis, RESTful Microservices, Web Security, WebSockets, APIs, Web Development, Scripting, Full-stack, Architecture, RPC, Chrome Extensions, Web Scraping, Technical Leadership, Native Mobile Apps, Mobile App Development, Fintech, Software Architecture, Technical Requirements, TypeORM, Digital Payments, Mobile Banking, OpenAI, MERN Stack, Scraping, GraphQL Code Generator, Apollo, Apollo Server, Team Leadership, Remote Team Leadership, Cross-functional Team Leadership, CI/CD Pipelines, GitHub Actions, Web3, RESTFul APIs, Large-scale Systems, API Design
Collaboration That Works
How to Work with Toptal
Toptal matches you directly with global industry experts from our network in hours—not weeks or months.
1
Share your needs
Discuss your requirements and refine your scope in a call with a Toptal domain expert.
2
Choose your talent
Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.
3
Start your risk-free talent trial
Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.
Top talent is in high demand.
Start hiring