Abraham Guerra
Software Architect / Tech Lead
I build complex backend systems for payments, commerce and integrations: security-sensitive flows that have to stay correct under retries, failures and concurrency.
From architecture decisions to hands-on delivery.
- Payments
- Commerce
- Integrations
- Backend platforms
- Reliability & security
Selected work
Problems and the decisions behind them
All work →01Payments · Commerce architecture
A reusable payment extension for Adobe Commerce, built to be distributed across merchants.
- Challenge
- Keeping a multi-step payment lifecycle correct under retries, duplicate submissions and concurrent requests.
- Status
- Advanced implementation, certification and marketplace-readiness phase.
- Adobe Commerce
- Idempotency
- Concurrency
- 3-D Secure
Read case →02Hardware · Software integration
Office access control in which a C# application verifies identity through a biometric reader and, on a successful verification, switches the relay that opens the door.
- Challenge
- Connecting identity verification in software to a real physical actuator.
- Status
- Implemented as a working office access-control system.
- C#
- Hardware integration
- Biometrics
Read case →Where a client cannot be named, the work is anonymized.
Independent systems
Systems designed and built on my own initiative
R&D environment that orchestrates specialized AI agents through a software-development workflow.
- Role
- Independent project: system design and build
- Status
- Working R&D system
- Agent orchestration
- Python
- FastAPI
- React
- Sandboxing
Read case →Profit Tracker
Multi-tenant SaaS that calculates historical profit for Mercado Libre sellers.
- Role
- Independent project: product, architecture and implementation
- Status
- SaaS prototype
- Multi-tenancy
- Node.js
- PostgreSQL
- React
- Mercado Libre API
Product Command Center
Platform to run catalog, inventory, pricing and sales for physical products across channels.
- Role
- Independent project: product, architecture and implementation
- Status
- Internal-platform prototype
- Commerce domain
- NestJS
- Prisma
- PostgreSQL
- Webhooks
Selected client work
Solutions delivered for clients
Aline Áwen
Website and administration platform for a singer and actress.
- Role
- Freelance: from requirements to deployment
- Status
- Live client site
- Next.js
- Cloudflare Workers
- D1 · R2
- Payments integration
alineawen.com ↗Payments & commerce
Payment lifecycles inside commerce platforms: authorization and capture, 3-D Secure, fraud screening, tokenization, post-payment operations and two-card checkout flows.
Backend architecture
Server-side systems and APIs across several stacks.
Integrations & distributed systems
Connecting commerce platforms, CRMs, carriers, mobile apps and public-sector systems, where data has to cross system boundaries intact.