JC
Julissa Cotillo

Ten years shipping production software.

I spent a decade as a software engineer, the last few years building production AI at enterprise scale: agents, context engineering, and LLM features. Today I build for my own companies, where the work is the automation that makes a small team feel bigger than it is, plus a handful of clients through Practical Works.

10 years

shipping production software

5 companies

healthcare, education, crypto, fintech

Founder

building on my own stack

The track record.

Practical Works

Now

Co-founder

2026 to Present

Remote

Co-founded an AI assessment and consulting studio that does what its name says: practical work that ships, no hype. From startups to mature companies, we find where AI actually fits and build the quick wins that pay for themselves.

Assessments turn into working pilots in four days, not four months, with the hours saved and the cost laid out in plain dollars.

OpenAIAutomationn8nNext.js

Breezy Keys

Now

AI Engineer and Co-founder

Oct 2023 to Present

Tampa Bay, FL

Co-founded a short-term rental management company and built the AI systems that run it: guest communication, dynamic pricing, and maintenance, all on a stack I operate myself.

Automated messaging now handles roughly 80% of routine guest inquiries, cutting response times from hours to minutes.

TypeScriptNext.jsMastraOpenAIGemini

Polly

Senior Software Engineer, AI Team

Oct 2024 to Jan 2026

Remote

Built production AI features for an enterprise mortgage and finance platform: real-time response streaming, retrieval pipelines, and intelligent LLM routing.

Shipped a citation interface that surfaced sources on every AI answer, making the system's reasoning auditable for the teams relying on it.

Vue 3TypeScriptRAGLLM routing

QuickNode

Software Engineer

Jul 2022 to Oct 2023

Remote

Core contributor to the QuickNode Marketplace launch, from billing and partner payouts to a load-testing microservice.

Onboarded more than 20 launch partners and built the Stripe integration that automated their payouts.

RubyGoTypeScriptGraphQLStripe

VitalSource

Senior Software Engineer

Jun 2017 to Mar 2022

San Francisco, CA

Co-led a four-person team modernizing the Verba faculty platform with GraphQL and TypeScript at university scale.

Delivered the adoption system used by 290+ universities and rebuilt logging across beta and production.

Ruby on RailsGraphQLReactAWS

Kipu Health

Software Engineer

May 2015 to Oct 2016

Miami, FL

Built scheduling and background-processing systems for a healthcare platform serving thousands of patients.

Eliminated up to two hours of background-task wait time and cut medical-form render time by 40%.

Ruby on RailsRedisSidekiqSQL

What I build with.

AI and ML

Agentic workflowsContext engineeringIsolated environmentsAgent controlLLM routingOpenAIMastra

Languages

TypeScriptPythonRubyGoSQL

Frontend

ReactNext.jsVueTailwindCSSGraphQL

Backend

Node.jsRuby on RailsREST APIsStripeMicroservices

Data and cloud

PostgreSQLRedisAWSGoogle CloudDockerKubernetes

Education and recognition

Boston University. BA, Economics and International Relations, cum laude

2014

Correlation One (DS4A). Data Engineering certificate

2023

Google for Startups. Gen AI: Building AI Agents

2024

QuickNode. HERO award for outstanding team and project contribution

2023

Airbnb. Superhost across a five-property portfolio, Guest Favorite within four months

Ongoing

Work with me.

Through Practical Works, I take on a small number of engagements for teams that want AI to earn its keep. The same engineering that runs my own companies, pointed at yours.

AI assessment

Where AI actually fits, and where it doesn't.

A focused audit of your operation that ends in a ranked list of quick wins you can act on, not a deck you file away.

Quick-win builds

Working pilots in days, not months.

I build the highest-leverage automation first and get it running on your real work fast, so you see value before committing to more.

Fractional AI engineering

Senior build help, on demand.

Ongoing help for teams shipping agents, context engineering, or LLM features into production, from someone who has done it at scale.

Have a problem worth solving?

Tell me what you are building. If AI can move the needle, I will tell you where. If it can't, I will tell you that too.