Daniel Gutiérrez — Portfolio

002 — By the numbers

4-15%

Revenue lift from production ML, owned end-to-end (NerdWallet)

Agentic

LLM agents grounded with RAG + tool calling (NerdWallet)

AWS

Cloud depth: Kinesis streaming, EKS/Fargate, CDK/SAM IaC

6-10×

Gateway latency 3-5s → <500ms via GraphQL gateway (CMG)

4-6

Engineers led across 3 teams, as lead & architect

0→prod

Greenfield product shipped in ~4 months

51K+

POS installs across 62 countries (Xenial)

10M+

Users on a consumer media platform — billions of photos (Shutterfly)

5

Platforms from one product: web, iOS, Android, Windows, desktop (Manhattan)

10+ yrs

Full-stack, cloud & ML across 4 industries

003 — Stack & experience

AI / LLM

Data/ML

Cloud/DevOps

Back-end

Front-end

Databases

Mobile

004 — Selected work

2023→ Present

NerdWallet

Senior Full-Stack & ML Engineer

Senior full-stack and ML engineer on a consumer-finance and credit platform, working end to end across the front-end, data pipelines, and production ML. Owned the ML workflow from data through modeling, training, and serving — a 4-15% revenue lift — shipped LLM-powered agentic workflows (RAG, tool calling), and revamped high-traffic customer-facing pages.

Owned the machine-learning workflow end to end, from data exploration and cleaning through modeling, training, and deployment. Drove a 4-15% revenue lift over the manual baseline
Shipped LLM-powered agentic workflows into customer-facing and internal products, using tool calling to retrieve and act on the product's own content instead of making users search for it
Built the retrieval-augmented (RAG) layer behind the agents, grounding their answers in internal documentation and product data so responses stayed accurate and tied to real sources
Built and orchestrated the data-engineering workflows (Apache Airflow) that ingest and clean customer and external data into the inputs feeding the ML models
Deployed models that analyze user behavior to optimize the pages, with observability on results and retraining loops so they kept improving as data shifted

Machine Learning
LLM integration
Node.js
Python
Data Engineering
AWS CDK
Snowflake
Apache Spark
Apache Airflow
AWS Lambda
+49

Next.js
GraphQL
AWS Kinesis
RAG
Tool calling
MLOps
TensorFlow
Keras
scikit-learn
Pandas
ABSmartly
Tensorflow.js
Anthropic SDK
Vercel AI SDK
AWS SNS
AWS SQS
AWS API Gateway
AWS AppSync
AWS S3
AWS CloudWatch
AWS IAM
AWS KMS
AWS SAM
AWS Fargate
Docker
Docker Compose
GitHub Actions
Feature Flags
Vercel
Apollo Server
REST
Django
FastAPI
SQL
DynamoDB
AWS Aurora
AWS RDS
PostgreSQL
React
TypeScript
Redux
Playwright
Jest
Vitest
React Testing Library
Material UI
JavaScript
HTML5
CSS3

2021→ 2023

Capital Markets Gateway

Tech Lead & Senior Software Engineer

Technical lead and senior engineer on a platform modernizing how institutions run capital-market operations, used by around 10 financial institutions. Led a 4-person team building advanced front-end features and designing the GraphQL gateway over complex backend services, across multiple domains.

Led front-end development across multiple domains, designing and building advanced features that improved functionality and workflow efficiency
Designed the GraphQL gateway fronting complex backend services and data sources, orchestrating intricate data workflows and improving the system architecture
Improved customer-facing page performance, cutting latency from 3-5 seconds to under 500ms by resolving N+1 query issues in the gateway
Implemented real-time data updates with SignalR to keep live data in sync. Built reusable component libraries in an Nx monorepo used across domains
Provided technical leadership: translating complex stakeholder requirements into work, coordinating delivery, mentoring teammates, and handling strict data-integrity flows where correctness was critical

Node.js
GraphQL
NestJS
Next.js
Redux
Amazon EKS
AWS API Gateway
CircleCI
AWS RDS
Playwright
+19

React
Apollo Server
SignalR
REST
Docker
Docker Compose
Feature Flags
SQL
PostgreSQL
TypeScript
Nx
React Testing Library
Jest
TestCafe
Material UI
Styled Components
JavaScript
HTML5
CSS3

2019

BrightInsight

Front-end Architect

Front-end architect and tech lead on a regulated, high-compliance healthcare product for blood-glucose monitoring and medication management. Led a 6-person team and owned the front-end architecture across two web applications delivering real-time patient monitoring.

Owned the front-end architecture across two web applications (Angular 2+ and React) with responsive, accessible interfaces. Delivered under regulated, high-compliance medical-software standards
Architected and built real-time monitoring of patient health data, including blood-glucose tracking, plus medication-management features. Integrated with backend services to power the patient-facing experience
Led and directed the development team, running code reviews and setting the front-end practices and code-quality standards

React
Angular 2+
NgRx
Node.js
Express.js
RxJS
Redux
Jasmine
TypeScript
Webpack
+5

JavaScript
REST
HTML5
CSS3
SASS

005 — Ways to work together

Problems I can own — as a hire, a project, or a collaboration.

Applied LLM & agentic systems

AI features your users can actually trust — grounded chat and agents that answer from your real data and docs instead of making things up, shipped into customer-facing and internal products.

Grounded RAG · tool calling · Anthropic & Vercel SDKs

Front-end & product UI

Fast, polished interfaces that convert — complex application front-ends, design systems, and accessible component libraries, plus conversion-focused marketing and landing pages.

React · Next.js · design systems

Cloud & data platforms

Cloud that scales and stays operable — AWS architecture end to end: real-time streaming and ML-scoring pipelines, serverless and containers, and infrastructure as code.

Kinesis · EKS/Fargate · CDK/SAM

Production ML that moves a metric

Models that actually move your business metric, not just offline accuracy — taken from notebook to production and owned end to end, with an evaluation framework that proves they're working.

Statistical / experiment-based evaluation · Snowflake

Greenfield product build

From idea to a shipped, working product — architecture, full-stack build, and a small team led from zero to production.

0 → production · architecture + small team led

Performance & cost optimization

Profiling an existing system to cut latency and clear bottlenecks — gateway and query redesign, data-flow rework (e.g. N+1 elimination), and right-sizing cloud infrastructure to match real load.

Profiling · query & data-flow rework · right-sizing

006 — Education & Certifications

Education

2020 - 2021

MSc, Data Science

ICESI University

2013 - 2018

BSc, Software Systems Engineering

ICESI University

Certifications

2023

AWS Certified Solutions Architect – Associate

Amazon Web Services (AWS)

2020

Scrum Master

CertiProf

007— Let's talk

Have a role or a project in mind?

Tell me what you need and I'll get back to you personally. Want to explore first? The chat at the top is grounded in my real experience.

or reach out directly

LinkedIn GitHub

Daniel Gutiérrez.