Alvaro Guzman Résumé ↓
Santo Domingo, DO · UTC−4

Senior full-stack engineer for payments and banking software.

.NET, Angular and TypeScript for 7+ years. I've shipped 60+ payment integrations, led a multi-country enterprise platform, and now build RAG and AI-agent developer tooling at Clarika.

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60+
payment APIs integrated, maintained and scaled · ATL Software
+15%
conversion; my checkout work contributed · ATL Software
Led
2RConnect, a multi-country enterprise platform · Wepsys
7+ yrs
full-stack .NET and Angular, remote and on-site
Experience

Where I've worked.

Full résumé (PDF) ↓
  1. Aug 2024 – Present

    Software Developer Clarika Software + Innovation

    Full-time · Remote

    Enterprise apps in .NET and modern frontends. Design and architecture decisions across distributed teams; internal developer tools built on RAG pipelines and AI agents, for autonomous and supervised development.

  2. 2024 – Present

    Full-Stack Developer InsolTech

    Part-time contract · Remote

    International banking applications and B2B migration projects in Angular and .NET, plus performance work on JavaScript and C# codebases.

  3. Jun 2022 – Aug 2024

    Full-Stack Developer ATL Software

    Full-time · Santo Domingo

    Integrated, maintained and scaled 60+ third-party payment APIs: checkout flows, transaction processing, fraud handling. Built the Ionic Angular commerce app; contributed to a 15% increase in conversion. Case study →

  4. Dec 2021 – Dec 2024

    Full-Stack Developer Wepsys

    Full-time contractor · Santo Domingo

    Led development and scaling of 2RConnect, a multi-country enterprise application serving users across several international markets. Architected its Angular and .NET apps with teams in several countries.

  5. Apr 2021 – Dec 2021

    Frontend Developer Centros Tecnológicos Comunitarios

    Hybrid · Santo Domingo

    Published an Ionic Angular app giving nationwide access to radio stations across the Dominican Republic. Moved legacy Loopback and PHP APIs to .NET 5.

  6. Nov 2019 – Present

    Freelance Full-Stack Developer Self-employed

    Freelance · Remote

    End-to-end web, desktop and mobile work for clients, including an on-premise LLM and RAG gateway for a bank. Case study →

The overlapping dates are real: contract and part-time work ran alongside full-time roles. Client and bank names stay private.

Stack .NET and C#, Angular and TypeScript day to day; also React, Vue, Svelte, Ionic, Laravel and PHP, Go and SignalR, on SQL Server, Postgres and SQLite, deployed to Azure, Docker and Cloud Run. C, Odin and Rust for systems work.

Selected work

Three case studies.

All work →
ATL Software · 2022–2024
60+ payment providers behind one checkout

An adapter contract per provider, a transaction state machine, and fraud checks ahead of capture. Checkout work contributed to a measured +15% conversion.

Angular · Ionic · .NET Read →
Freelance engagement · Banking
An on-prem LLM gateway for a bank

Multi-provider model routing, RAG with vector search and multi-agent orchestration in C#/.NET, with zero external data egress by construction.

C# · .NET · RAG Read →
Personal · Live
c-copper, the C server behind this site

Socket loop, router, middleware chain, template engine and gzip, hand-written in C99. It rendered this page in 0.42 ms.

C99 · pthreads · zlib Read →
Terminal

Ask the server directly.

A small shell wired to this site. status reads live numbers from /api/status on the C server; help lists the rest.

c-copper shell Tap to try the terminal
$ 
Contact

Hiring a senior or staff engineer? Let's talk.

Email is fastest and I reply within 24 hours. Full-time through an employer of record, or a long-term contract.

aagn2807@gmail.com LinkedIn GitHub Contact form →