João Sampaio

Email: // Website: // Location: Brazil
Latest revision of this resume: // This revision: 2022.04.03

Professional Experience

Close Remote
Senior Backend Engineer August 2019 to present

Close is an all-in-one CRM that eliminates manual data entry and focuses on results-oriented communication.

  • Implemented new features and fixed bugs in the backend and infrastructure of the product;
  • Wrote tests to ensure consistency and avoid regressions as new features are implemented;
  • Participated in discussions about the design of new features in the product;
  • Led projects as a technical project lead, doing preliminary spec work, planning development and estimating effort.

Technologies used: Python, Flask, Pytest, PostgreSQL, MongoDB, AWS, Docker, Git, CircleCI.

AlayaCare Full-time, Montreal, Canada
Software Engineer May 2018 to April 2019

AlayaCare is a provider of revolutionary cloud-based home healthcare software. With an end-to-end solution spanning clinical documentation, back office functionality, client and family portal, remote patient monitoring, and mobile care worker functionality, AlayaCare offers a platform for agencies to propel towards innovation and home care of the future.

  • Implemented new features and fixed bugs in several parts of the product;
  • Participated in discussions about infrastructure and design of the platform;
  • Worked on development from frontend with Vue.js to backend with PHP, Symfony, Python and Flask;
  • Refactored the integration tests architecture and infrastructure to provide a more robust platform on top which the development team could implement fast and reliable tests to assure the quality of each release.

Technologies used: Python, Flask, Pytest, Pytest-BDD, Selenium, PostgreSQL, MySQL, AWS, Docker, JavaScript (ES6), Vue.js, Git, JIRA.

AdRoll Full-time, Remote
Software Engineer April 2017 to April 2018

AdRoll is one of the biggest ad platforms in the world, focused mostly on small and medium businesses, but also has products and services for big enterprises. It optimizes their ad investments based on a budget and strategies of retargeting, prospecting and email marketing, giving a high return on investment in a short timeframe.

  • Implemented solutions for new customers to quickly and efficiently start using all the company's products and services;
  • Participated in discussions about infrastructure and design of the platform;
  • Worked on development from frontend with React.js to backend with Python and Flask;
  • Implemented new real-time big data processing topologies using Hadoop, processing massive amounts of data received daily, in a constant stream, from our customers and customers of customers.

Technologies used: Python, Flask, Luigi, Java, Hadoop, HDFS, PostgreSQL, DynamoDB, AWS, Docker, JavaScript (ES6), React.js, Bootstrap, Git, HighCharts, JIRA.

Trounceflow Full-time and freelance contractor, Remote
Senior Software Engineer October 2016 to November 2017

Trounceflow uses Python scrapers as background automated processes to find and analyze massive financial data from various websites and APIs. The data is plotted in charts to provide insights to customers, allowing them to make critical financial decisions faster in the super competitive financial market.

  • Started leading the quality team and finally the entire engineering team from building the software from scratch all the way to the acquisition of the first clients;
  • Final responsible for the delivery of the various software stages and implementation decisions, from internal class architecture and database schema to deployment and infrastructure;
  • Created a system that finds and analyzes massive amounts of financial data and plots graphs, in order to make their analysis easier.

Very hands-on management experience, the company being new and very agile. Involvement in every technology-related activity and decision.

"A thoroughly excellent experience, João did a really good job here. Thank you, João, you are welcome back any time." -- Michael Trounce, CEO

Technologies used: Python, Django, Django REST Framework, Celery, RabbitMQ, Redis, PostgreSQL, Javascript (ES6), jQuery, Bootstrap, Heroku, AWS, HighCharts, Git, Tkinter, multi-threaded desktop applications, Kanban, Scrum, JIRA.

Freelancer Full-time, Remote
January 2008 to October 2016

Worked with various clients delivering from simple landing pages to complex web applications based on distributed systems, asynchronous workers, databases, caches, etc. All projects were done in Python and Django, with usability and scalability in mind. Some clients and projects include:

  • Ideation Brasil: Ideation Brasil manages business competitions for college students, with the objective of closing the gap that keeps the industry from dormant potential in academia. Long-term client from February 2014 to October 2016, started with a simple institutional website for their business, then a second version of the website and, finally, a platform for managing users, companies, competitions, subscriptions, rankings and prizes. The project involved a clean user interface, databases, caches, asynchronous workers, access to external APIs and more;
  • Event management system for X SEMATRON: SEMATRON is the most important event for Mechatronics Engineering students in Brazil. An event management system was created from scratch. Participants can sign up to the event, select which lectures and hands-on workshops they wanted to attend, and the system read bar codes from student name tags to confirm attendance to selected events. Students with at least 70% attendance across all events could request a certificate of attendance. The system communicated through a REST API with a Brazilian payment gateway to confirm paid subscription fees.

Technologies used: Python, Django, Django REST Framework, Celery, RabbitMQ, Redis, Memcached, PostgreSQL, Javascript (ES6), jQuery, Ember.js, Bootstrap, Heroku, AWS, Git, Kanban, Scrum, JIRA.

Async Open Source Part-time, São Carlos, SP, Brazil
Software Engineer July 2012 to October 2013

Async develops Stoq, an ERP system for small and medium-sized companies that includes point of sales, warehouse management, sales and staff reports, a CRM and more.

  • Desktop development in Python with PyGTK. Developed new features, fixed bugs and wrote automated tests for Stoq;
  • Using Django, started the effort of creating a web-based interface for Stoq and the system to migrate clients from the desktop app to the web app.

Technologies used: Python, Django, Nose, PyGTK, OpenVPN, Git, Bazaar, Bugzilla.


Universidade Federal de São Carlos São Carlos, SP, Brazil
Computer Engineering July 2014


English: fluent; Portuguese: native; French: reading proficiency.