Hi, I'm Joaquin Mellado

I build software that helps products move forward.

Senior Full-Stack Software Engineer building reliable AI-enabled products with React, TypeScript, Python and cloud infrastructure.

Product-minded Software Engineer

I connect software engineering, product judgment, frontend craft, and practical AI workflows to build things people can understand, trust, and use.

Selected Work

Case studies coming soon.

I'm preparing concise case studies about the architecture, decisions, tradeoffs, and results behind the products I've built. Each one will show real problems, real code, and real outcomes.

YieldAI

An AI-powered research assistant for dividend investors, combining financial data pipelines, multi-agent risk analysis, RAG over SEC filings, and explainable portfolio research simulations with compliance guardrails.

Educational research tool — not financial advice.

Tech stack

Next.js FastAPI PostgreSQL/pgvector Docker LangGraph Langfuse

Architecture flow

Query Data Risk Build Report
Case study coming soon

Why now

Why product-minded engineering matters now.

AI makes it easier to generate interfaces, features, and code. That makes judgment more valuable, not less. The real advantage is knowing what should exist, what should be removed, what should be measured, and where the product is actually failing.

More output is not more value

AI can accelerate production, but it can also multiply weak ideas, unclear flows, and forgettable interfaces.

Users feel quality instantly

Speed, clarity, accessibility, and reliability shape trust before a roadmap or feature list does.

Architecture affects product speed

Technical decisions decide how safely teams can change, learn, and ship without creating invisible drag.

Signals beat opinions

Strong teams use behavior, friction, retention, and feedback to guide what they build next.

What I have actually learned

The useful stuff usually shows up in the messy signals.

I have worked across banking, large-scale frontend platforms, internal risk workflows, and a startup MVP I founded. Different contexts, same lesson: software quality matters when it helps people make progress.

I go looking for the uncomfortable numbers.

Error rate, LCP, drop-offs, slow flows, support signals, and observability data often say more than a polished demo.

Observability is product work when you use it well.

Adobe, Datadog, and platform metrics are not only engineering dashboards. They can show whether a product is actually working for people.

Architecture is usually about teams, not diagrams.

Microfrontends, shared packages, and modular boundaries only help when ownership and change patterns are clear.

I keep coming back to experiments.

I am always looking for opportunities to start, test, and learn from products. It is probably the best moment we have had to do it.

What I care about

The concerns behind the craft.

Good software is the baseline. The harder question is whether the product creates value, changes behavior, earns trust, and stays maintainable while moving fast.

Memorability

Will people remember this experience, or is it just another interface?

Real value

Are we solving a painful problem or just shipping visible activity?

User behavior

What are people actually doing, repeating, avoiding, or abandoning?

AI leverage

Is AI improving judgment and speed, or only increasing output volume?

Frontend quality

Does the product feel fast, clear, accessible, and trustworthy?

Sustainable speed

Are we moving fast without creating invisible drag for the team?

Signals I hunt for

Product Market Fit (PMF)

People come back because the product solves something that matters.

Retention

The experience keeps producing value after the first visit.

UX friction

Confusion, hesitation, repeated steps, and drop-offs become design input.

Performance

Speed becomes part of trust, conversion, and perceived quality.

North Star

The team aligns around value, not vanity dashboards.

Technical debt

Tradeoffs are explicit, intentional, and visible before they become drag.

Traps I avoid

Scope creep

More features can make the product less memorable.

Vanity metrics

Numbers that look good can still hide weak product learning.

Hidden complexity

A clean UI can hide expensive decisions and future maintenance cost.

Slow feedback

Long feedback loops weaken product judgment and delivery quality.

Product OS

A loop for building useful things.

I work from ambiguity to shipped behavior through a simple loop: discover, shape, build, measure, iterate.

See how I build
1 Discover the real problem
2 Shape the smallest useful version
3 Build with craft
4 Measure signal
5 Iterate with intent

Field notes

Real product engineering judgment.

The strongest frontend decisions are rarely just technical. They shape team autonomy, delivery speed, product risk, and the cost of future change.

Architecture tradeoffs

Choosing architecture is a product decision.

In large frontend systems, I have seen architecture choices affect how safely teams ship, how independently they can work, and how expensive product changes become. Microfrontends, module federation, shared libraries, and modular monoliths are not maturity levels. They are tradeoffs.

Microfrontends

More team autonomy, but more operational and integration complexity.

Module federation

Flexible runtime composition, but harder debugging, versioning, and ownership.

Shared libraries

Better consistency and reuse, but possible release bottlenecks and coupling.

Modular monolith

Simpler delivery, but it needs strong boundaries to avoid slow entropy.

The best architecture is the one that matches the product's rate of change, team structure, risk profile, and learning needs.

High-risk banking flows

Transfers, onboarding, and account management taught me that reliability, clarity, and performance are product features, not engineering details.

Founder to MVP

Building BinnApp from idea to MVP taught me to reduce scope, coordinate product discovery, and make technical decisions under uncertainty.

Proof of craft

This landing is part of the product.

The signal game is not decoration. It is a small metaphor for how I build: identify valuable signals, avoid expensive traps, move with intent, and unlock better decisions.

If this is how I design a portfolio interaction, imagine how I approach real product flows.

When I can help

Bring me in when the product needs clear thinking and hands-on execution.

I work best when there is something real to figure out: what to build, what to simplify, what is breaking, and how to ship without hiding future cost.

You have an idea, but the product experience still feels vague.

I can help turn ambiguity into flows, decisions, and shipped behavior.

Your frontend is slowing product decisions down.

I look at architecture, performance, UX clarity, and maintainability as part of the same problem.

Your team needs someone who can build and question scope.

I care about shipping, but also about removing work that does not help people make progress.

Start a conversation

Work with me

Need a technical partner who thinks product?

If your product needs sharper decisions, stronger frontend quality, or AI-aware execution, let's talk.