Santlar Labs

Software studio · English & Español

Custom software that runs your business — built to enterprise standards.

I design and build web apps, online shops and automation tools for small and mid-size businesses. The same engineering I've delivered for Fortune 500 teams, sized for your budget.

Start a projectSee the work

  • 12+

    years building production software

  • 80–90%

    faster response times delivered

  • 99%

    uptime on deployed applications

  • EN · ES

    bilingual, US & Latin America

Engineering experience with teams at

Services

What I build for you

One engineer from first sketch to production — no hand-offs, no lost context.

Custom web apps & SaaS

Dashboards, client portals and full SaaS products that replace spreadsheets and manual steps with one reliable system.

Online shops

Fast, good-looking stores that are easy for you to manage — products, payments, inventory and orders in one place.

Automation & internal tools

Tools that take repetitive work off your plate: scheduling, social media, reports, notifications and integrations between your apps.

Modernization & performance

Slow or aging system? I migrate legacy code to modern stacks, speed up APIs and move apps to the cloud without breaking what works.

Selected work

Recent projects

Current freelance clients and highlights from enterprise engagements.

Online shop for video game collectibles

PauReinaPolilla · Content creator

Live

Online shop for video game collectibles

Designed and built Polillita Shop, a bilingual store for exclusive video game collectibles shipped across Mexico, with a product catalog, pre-orders, cart and customer accounts.

  • E-commerce
  • Bilingual ES/EN
  • Pre-orders
  • Customer accounts
Visit site
Screenshots coming soon

PauReinaPolilla · Content creator

In development

Social media management app

A custom app to plan, organize and manage content across her social networks from one place, saving hours every week.

  • Web app
  • Automation
  • APIs
Screenshots coming soon

Auto repair business · Automotive services

In development

SaaS for vehicle repair workflows

A platform that automates the full repair process — intake, diagnosis, parts, status updates and delivery — so the shop runs on one system instead of paper and phone calls.

  • SaaS
  • Workflow automation
  • Full-stack

Fortune 500 financial services · Enterprise

Enterprise

Legacy service modernization

Migrated legacy SOAP services and DB2 stored procedures to modern REST and gRPC microservices, and cut response times by 80–90% with concurrency and query tuning.

−80–90%response time

  • Java 21
  • Spring Boot
  • gRPC
  • Kafka

Class I railroad · Enterprise

Enterprise

Rail operations analytics tools

Built the interface for yard capacity simulations and reporting tools with interactive maps and charts, deployed to Kubernetes with 99% uptime.

99%uptime

  • React
  • TypeScript
  • OpenShift
  • Maps

Process

How a project works

Clear steps, fixed milestones and a working demo every week.

  1. 01

    Discovery call

    A free 30-minute call to understand your business, the problem and what success looks like.

  2. 02

    Proposal & plan

    A written scope with milestones, timeline and a fixed price per milestone. No surprises.

  3. 03

    Build in the open

    Weekly demos you can click through, so you see progress and can steer early.

  4. 04

    Launch & support

    Deployment, training for your team, and optional monthly care for hosting, fixes and new features.

Ways to work together

Fixed-price project

Best for a defined product: a shop, an app, a SaaS MVP. Paid by milestone.

Monthly care plan

Hosting, monitoring, updates and a block of hours for improvements each month.

Consulting & rescue

Code reviews, performance fixes or taking over a project that got stuck.

About

Hi, I'm Daniel Santiago

I'm a full-stack software engineer with more than 12 years of experience. Most of that time I've worked inside large companies — banks, insurers, telecoms and a major US railroad — building systems that can't afford to go down.

I started Santlar Labs to bring that same level of engineering to small and mid-size businesses: software that is reliable, fast and built around how you actually work. I speak your language too — literally. I work in English and Spanish with clients across the US and Latin America.

Outside client work, I hold a master's degree in video game design and development, and I'm building a roguelite in Unity for Steam.

Tools I work with

  • Java
  • Spring Boot
  • TypeScript
  • React
  • Next.js
  • Angular
  • Node.js
  • PostgreSQL
  • MongoDB
  • Kafka
  • gRPC
  • Docker
  • Kubernetes
  • GitHub Actions
  • Unity

Experience

  1. 2025 — now

    Full-Stack Developer

    Fortune 500 financial services company

  2. 2020 — 2025

    Full-Stack Developer

    Norfolk Southern (via Aptonet)

  3. 2018 — 2020

    Java Developer

    HSBC · Telcel · BBVA

  4. 2013 — 2018

    Java & Lead Developer

    Premium Restaurant Brands (Pizza Hut, KFC)

FAQ

Common questions

Do you work with small businesses?

Yes — that's my main focus. Most projects start small, with an MVP that solves your most painful problem, and grow from there.

Can we work in Spanish?

Absolutely. Calls, documents and the software itself can be in English, Spanish or both.

How much does a project cost?

It depends on scope. After the discovery call you get a written proposal with a fixed price per milestone, so you always know what you're paying for.

What happens after launch?

You can take the project in-house, or keep me on a monthly care plan for hosting, monitoring, fixes and new features.

Contact

Let's build something that works for you

Tell me about your business and what you need. I reply within one business day.

Or email me directly

dann.santlar@gmail.com
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