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Gabriel Alves Silva

@gabrielalvessilva

Message

Backend software engineer focused on scalable Python APIs, authentication integrations, and performance optimization.

Brazil

Message

What I'm looking for

I’m looking for a backend role where I can build scalable Python APIs and data solutions, optimize database performance, and own secure authentication and integrations (OAuth2/SSO/JWT, webhooks), backed by solid automated testing.

I’m a Backend Software Engineer with 5+ years of experience building scalable, high-performance APIs and data solutions with Python, Django, Django REST Framework, FastAPI, SQL, and AWS. I’ve structured endpoints serving 20,000+ concurrent users, cut SQL query cost by 98% and execution time by 44% through Django ORM optimization, and led an integration system that prevented ~$300K in fraud.

Right now, as a Senior Software Engineer at Cakto, I optimize PostgreSQL queries using Django ORM, eliminate N+1 problems, and improve search and aggregation performance while delivering faster API responses. I also restructure authentication and authorization with SSO (Single Sign On) and OAuth2, develop webhooks for system synchronization, and back everything with automated unit/integration testing using Pytest, Unittest, and mocks—bringing a strong focus on maintainability, security, and reliability.

Experience

Work history, roles, and key accomplishments

Current

Senior Software Engineer

Current

Cakto

Jul 2025 - Present (1 year 1 month)

Optimized PostgreSQL queries using Python Django ORM by eliminating N+1 issues and improving indexes, reducing operation cost by 98% and execution time by 45%. Led authentication (password-less, SSO, OAuth2) and built Django REST Framework webhooks and REST APIs with automated testing.

Python Django PostgreSQL SQL N+1 Query Optimization Indexing API Development Django REST Framework SSO JWT Webhooks Throttling Middleware REST APIs Pytest Authentication and Authorization

Current

Software Engineer (Freelance)

Current

Self-employed

Feb 2021 - Present (5 years 6 months)

Developed multiple Python-based systems, including a multi-tenant cryptocurrency monitoring platform handling up to 30,000 simultaneous requests. Built RPA/web scraping pipelines and automation features using Selenium/Scrapy and reduced data retrieval and storage times with Python, SQL, and AWS-hosted infrastructure.

Python SQL Django API Integration PostgreSQL OpenAI API Automation Selenium Excel Pandas Google Sheets Scrapy Docker Git Linux Nginx

Tech Lead

Cordeiro Energia Solar

Jan 2025 - Oct 2025 (9 months)

Owned technology decisions, project structure, and implementation of backend workflows, including payment confirmation and document/protocol handling. Integrated the system with the company CRM via webhooks and built UI and monitoring components using HTML/CSS/Bootstrap/JavaScript and Power BI.