LT

Senior Software Engineer | Technical Lead | Software Architect

Luis Trejos

Manufacturing platforms, AI document pipelines, and the teams that ship them.

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Background

Full-stack engineer with 15+ years crafting and maintaining robust, scalable applications. Passionate about developer experience, good practices, performance, automation, and shipping products that create value for teams and, most importantly, users. I thrive in both the technical and non-technical sides of software development. Let's connect!

Luis Trejos
Heredia, Costa Rica
luis.trejos.tabares@outlook.com
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Career

Experience

  1. 2021 – Present

    Senior Software Engineer

    Cargill

    Design, implement, and support manufacturing applications — from web UIs to backend systems and plant-floor connectors. Collaborate with cross-functional teams in Agile/Scrum to improve production processes and operational efficiency.

    Key Achievements:

    • Led a manufacturing data hub that cut operational errors by 60% and delivered more than $1M in savings across 6 facilities.
    • Built a GenAI document processing engine that reduced manual processing time by 80% in the first 4 months, with 100K+ documents projected over 5 years.
    • Currently leading a poultry management platform projected to save $600K a year by replacing a SaaS dependency.
    • Led 12+ engineers across these products, mentoring and guiding technical decisions.
  2. 2025Contract · concurrent with Cargill

    Senior AI Software Engineer

    DevBlock Technologies

    Built AI-driven product prototypes under ambiguous requirements, shipping weekly progress with the CTO, product, engineering, and the client.

    Key Achievements:

    • Prototyped a solution that ingested 3 unstructured data formats using OCR and LLM prompting.
    • Ran 10+ demos with clients and stakeholders to lock next steps in the product.
  3. 2024Contract · concurrent with Cargill

    Senior Software Engineer

    Shrine Development

    Helped a healthcare clinic-and-patient platform migrate on-demand AWS Lambda functions to a Docker-based environment, working in Agile/Scrum.

    Key Achievements:

    • Refactored and migrated 5+ Lambda dependencies into the new Docker strategy during a two-month tenure.
    • Integrated SonarCloud into the unit/integration testing pipeline and refactored 30+ tests around Lambda deprecation.
  4. 2017 – 2021

    Senior Software Engineer

    Fiserv

    Served as Senior Software Engineer and Technical Lead on FinTech products — mission-critical ETL and client-facing applications — in Agile/Scrum.

    Key Achievements:

    • Led 2 developers and 2 QAs to deliver an onboarding implementation covering 2K+ accounts.
    • Migrated 5K+ customer accounts from a legacy Vehicle Remarketing system into the platform.
  5. 2014 – 2017

    Software Engineer

    Fiserv

    Modernized FinTech processes spanning legacy desktop apps and internal tools.

    Key Achievements:

    • Migrated a fax processing service from VB6 to C# and .NET Framework 4.5 to keep critical operations running.
    • Resolved 50+ production issues during the first year in the role.
  6. 2011 – 2014

    .NET Development Specialist

    B&T Consulting

    Worked as a specialized .NET developer on financial-industry projects, from Excel integrations to WCF services that interfaced with SAP.

    Key Achievements:

    • Modernized a classic ASP idea-submission app to ASP.NET with new infrastructure, mail, database, and RBAC — scoped for 500+ visits a month.
    • Refactored a calculation engine and cut performance issues by 90%.

What I work with

Tech Skills

Languages

  • TypeScript
  • JavaScript
  • Python
  • SQL
  • C#
  • Go

Front-End

  • React
  • Next.js
  • TanStack Router
  • Vite
  • Tailwind CSS
  • Material UI
  • Ant Design
  • Bootstrap
  • KendoUI

Mobile

  • React Native
  • Android Studio
  • Redux
  • Realm
  • Bitrise

Back-End

  • Node.js
  • FastAPI
  • Django REST Framework
  • Flask
  • Spring Boot
  • NestJS
  • ASP.NET
  • GraphQL
  • REST APIs
  • Celery

Data & AI

  • PostgreSQL
  • MSSQL
  • Snowflake
  • Redis
  • Hadoop
  • OpenAI SDK
  • OCR
  • OSI PI
  • AVEVA Connect

Tooling & Infra

  • Docker
  • Kubernetes
  • AWS (EKS · S3 · Lambda)
  • Azure Cloud
  • Datadog
  • SonarCloud
  • GitHub Actions
  • Azure DevOps
  • Portainer
  • Kong

Personal products

Portfolio

ATS Genie

A one-session tool to analyze or assemble a resume so applicant tracking systems can parse it. Nothing is stored. There are no accounts.

  • Analyze a PDF/DOCX or assemble sections in plain text, then download DOCX or PDF.
  • Rewrites via GPT-OSS 120B on Groq, with 3 AI checks per IP per hour.
  • Request-scoped processing only — no database and no resume logs.
Next.jsFastAPIGroqTailwind CSSVercelRender
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Selected work

Projects

Poultry Management System

Full-stack platform for the poultry production lifecycle, built to replace a SaaS product and scale globally.

  • Projected $600K/year in operational savings by replacing the current SaaS solution.
  • Designed to scale to 5+ countries in two years, including Europe and Asia.
  • Took over as technical lead and designed the front-end, back-end, and data model — 30+ tables across 4 domains.
PythonFastAPIReactPostgreSQLAWS EKSKubernetes

Manufacturing Data Hub

Central hub that aggregates manufacturing data from plant historians and warehouses so operators can act on one source of truth.

  • Reduced operational errors by 60%, more than $1M in savings across 6 facilities.
  • Delivers 20+ KPIs in near real time to plant operators and supervisors.
  • Replaced a SaaS contextualization tool in under 2 months, avoiding downtime on 15+ pipelines.
PythonDjango REST FrameworkFastAPISnowflakeReactAWS

GenAI Document Processing Engine

OCR and LLM pipeline that turns PDFs, Excel, and Word files into structured data for technical writers.

  • Cut manual processing time by 80% within 4 months of launch.
  • Built to handle 100K+ documents over 5 years.
  • One pipeline for 3 unstructured document formats.
PythonOpenAI SDKOCRAWS S3PostgreSQLSpring Boot

Seed Quality Computer Vision Inspector

Computer-vision MVP that helps crushing-plant operators judge seed quality from images and write results back to the plant historian.

  • Reduced manual seed-quality checks by 30% with inference-model integration.
  • MVP became the baseline for a product rolled out at global scale.
  • Closed the loop by publishing quality results to OSI PI for traceability.
ReactTypeScriptPythonGoPostgreSQLKafka

AI-Powered Order Processing

Prototype that reads orders from email, PDFs, images, and spreadsheets and posts them into Shopify without manual entry.

  • Prototyped ingestion of 3 unstructured data formats with OCR and prompting.
  • Wired Postmark email webhooks and the Shopify Store API for live product updates.
  • Ran 10+ client and stakeholder demos to steer the next build.
Next.jsReactOpenAI SDKShopify APIPostmarkTypeScript

Banking Servicing Platform

Servicing platform for customer accounts and loans, used by some of the largest vehicle manufacturers in the US.

  • Led 2 developers and 2 QAs to onboard 2K+ accounts.
  • Migrated 5K+ customer accounts from a legacy Vehicle Remarketing system.
  • Moved 50+ SQL views onto Azure SQL.
ASP.NETC#MSSQLKendoUIRedisAzure Cloud

Say hello

Contact

Whether you have a project in mind, a question, or just want to connect — feel free to reach out.

Email

luis.trejos.tabares@outlook.com

Phone

+506 8880 5209

GitHub

@luis-trejos-tabares-gh
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