SOFTWARE ENGINEER | CYBERSECURITY

Kleyson Carreira

Over 10 years in software engineering, today focused on international multi-tenant SaaS platforms and automation

About

CTO and co-founder of ZapYou. Over 10 years writing software, most of it spent on the operational problems nobody wants to touch.

At ZapYou I handle the architecture and development of a WhatsApp Business communication platform integrated with Meta's Cloud API as a Tech Provider, where each client operates its own WABA with no reseller layer. Day to day that means per-tenant data isolation at the ORM layer, idempotent message delivery with webhooks that arrive out of order, and LGPD solved in the design of the system.

Alongside that I take on custom software through ARIERRAC INC and maintain open source projects, among them a tool for scheduling and verifying database backups. At IPOG I build the internal systems used by campuses across Brazil, and at Espaço Paulista I run the network and the live streaming for events. Very different contexts, usually the same problem: understanding the operation before writing any code.

I understand the business problem before choosing the technology.
Most of the decisions I make are about what not to build.
I operate what I build.
Own servers, Docker, Cloudflare, observability and incident response. That changes how you write code.
Security is not a final step.
I run periodic audits of the codebases I maintain against OWASP, and treat threat modeling as part of designing any feature that touches customer data.

Experience

Apr 2023 — presentSão Paulo, Brazil · Hybrid
CTO & Co-founder
ZapYou
Architecture and development of a multi-tenant SaaS platform for WhatsApp Business communication, integrated with Meta Cloud API as a Tech Provider. Per-tenant isolation at the ORM layer, idempotent message delivery and LGPD as a design requirement.
May 2020 — presentSão Paulo, Brazil · Hybrid
Full Stack Developer
IPOG São Paulo
I build internal software used not only by the São Paulo campus but by several units across Brazil. The focus is removing operational bottlenecks: automating manual routines, integrating systems that did not talk to each other and giving time back to the academic, sales and administrative teams.
Jul 2019 — presentBrazil · Remote
Kleyson Carreira
ARIERRAC INC
Custom software and maintenance of open source projects, among them a tool for scheduling and verifying database backups.
Jun 2016 — presentSão Paulo, Brazil
I.T Manager
Espaço Paulista de Eventos
Responsible for the internal and external networks shared across the rental venues, ensuring segmentation, availability and capacity for simultaneous events. I also own the recording and live streaming system for hybrid and remote events, from the audio and video signal to final delivery.

Stack

Backend

TypeScript
Node.js
Fastify
NestJS
Prisma
Python

Frontend

Next.js
React
Vue.js
Tailwind CSS

Data

PostgreSQL
Redis
Qdrant
MongoDB
MySQL

Infra and operations

Docker
Kubernetes
Terraform
Cloudflare
NGINX
Linux
AWS
GitHub Actions

Security

OWASP
Threat modeling
Web pentest
Burp Suite
Nmap
Wireshark
Kali Linux

Certifications · 90

Contact

Let us talk.

Open to conversations about multi-tenant architecture, Meta platform integrations, application security and process automation.

[email protected]github ↗linkedin ↗

Kleyson Carreira

About

I understand the business problem before choosing the technology.

I operate what I build.

Security is not a final step.

Experience

CTO & Co-founder

Full Stack Developer