Cristhofer Cousiño

Software Engineer · Freelance

Custom software for clients in Chile and the United States: backend services, internal tools and user-facing applications.

• Built an accounting automation portal for a US construction firm: three FastAPI services behind a Next.js front end, Microsoft Entra ID single sign-on, role-based access and an audit log.
• Shipped product and marketing front ends in Next.js and React, plus the REST APIs behind them, with explicit contracts and versioned PostgreSQL migrations.
• Ran client work end to end in English: scoping, delivery on a date, and handover that stayed maintainable.

Lead Software Engineer · Replicator Platform

Led design and development of a BI and data replication platform connecting legacy ERPs with modern analytics workflows.

• Designed a hybrid multi-tenant model in PostgreSQL: one schema per tenant for ERP data, row level security for shared metadata.
• Built a replication engine in Java 21 that discovers legacy ERP schemas, runs full or incremental loads, and streams into Postgres in binary format.
• Delivered a Next.js front end with a visual query builder, drag-and-drop dashboards and S-curve financial forecasting.
• Deployed AWS infrastructure using Secrets Manager for external credentials and OAuth2/OIDC for identity.

Replicator

High-performance SaaS platform designed for the construction industry to unify data from fragmented ERP systems (Viewpoint Vista, Spectrum) into a centralized analytics warehouse.

Completionist

Go-powered social tracking backend with real-time messaging, challenge systems, and multi-provider media integrations.

Total Trades Integrated

Brand website for a commercial and industrial contracting firm specializing in MEP, welding, and construction.

688labs

Software studio I founded with a friend. Bilingual site for the studio, presenting what we build and how we work.

Accounting Automation Portal

Internal automation portal for a construction company's accounting team, covering lien waiver generation, vendor compliance tracking, and outgoing email review.

SaaS Scheduling System

Enterprise-grade SaaS for service businesses featuring robust booking logic, multi-tenancy, and integrated Point of Sale.

Habit Tracker

Solo-first habit tracker with a Go API and Next.js frontend, focused on server-authoritative progression and actionable analytics.

Hero Arena Gamemode

Round-based hero PvP gamemode and tournament backbone for a Minecraft event server running multiple minigames across a connected network.

Minecraft Chaos Randomizer

A Paper plugin that turns Minecraft into a brutal hardcore experience with 50 tunable chaos events, randomized drops, and horror mechanics.

Software Development (Self-Taught) · Self-taught

Learned independently through documentation, videos, exercises, and personal projects.