gfernandescwb

Senior Backend Dedveloper

I work with cryptographic systems and blockchain infrastructure, from protocol-level
components to practical applications, grounded in a background in Mathematics that shapes how I approach protocol design and correctness.

My work involves building and maintaining systems where financial value, data integrity, and distributed coordination are critical, primarily using Go, Rust, and Node.js. This includes both newer architectures and existing systems that still carry operational weight. I move between protocol-level concerns and implementation, connecting crypto-graphic primitives with backend services and application layers.

Part of my work involves dealing with legacy systems. This includes understanding existing structures, maintaining them, and extending them without breaking what is already in place. I work across the stack when needed, from data and backend services to user-facing applications, with attention to consistency, auditability, and predictable behavior. Technical writing is part of the process, especially in regulated or high-assurance environments where clarity and precision are required.


Experience: 7 years

Yearly salary: $72,000

Hourly rate: $50

Nationality: 🇧🇷 Brazil

Residency: 🇧🇷 Brazil


Experience

Software Developer
Quantum Theorem Ltda
2020 - 2025
I have hands-on experience building Web3 systems, including multi-chain wallet infrastructure, OTC platforms, atomic micro-swaps, and HTLC-based cross-chain exchange mechanisms. I implement these solutions with a strong focus on WASM for secure, portable and deterministic execution environments, ensuring isolation and auditability across different runtimes. My background also includes delivering cryptographic and transactional systems for fintechs and the banking sector, where I design and integrate high-assurance protocols that combine modern primitives such as threshold signatures, distributed key generation and authenticated encryption with real-world regulatory and operational constraints.

Skills

api
architecture
backend
bitcoin
blockchain
cobol
cryptography
devops
docker
dot-net
ethereum
git
golang
haskell
java
javascript
kotlin
kubernetes
linux
nosql
php
polygon
postgres
python
rust
solana
solidity
sql
typescript
full-stack
english
russian
spanish