>_ Daniel Sierra

AI Product Engineer

I build complete AI-powered products and help companies do the same.

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Daniel Sierra

I'm Daniel, an engineer with 11 years of experience in tech. I started in AI consulting, founded my own company, and now I build complete AI products end-to-end. From data engineering pipelines and LLM integrations to AI-powered products in your pocket.

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Have a look at my last work

01

Fitizens — The AI Fitness Coach

Co-founded and built the entire tech stack for an AI-powered fitness app: 19 repos, 200+ real users, two major pivots.

19 repos3 apps2 pivots
Fitizens — The AI Fitness Coach

Tech Stack

Programming Languages

PythonDartCC++

Mobile & Frontend

FlutterRiverpod

AI & LLMs

Gemini / Vertex AIOpenAIAnthropicQwenKimi

Backend & Cloud

FirebaseGoogle CloudAWSAzure

Data & ML

Pandas / PolarsScikit-learnTensorFlowPyTorch

DevOps & Tools

GitGitHubClaude CodeOpenClaw

Let's build something together

Have a project in mind? I'd love to hear about it.

Get in touch