Sebastian Ortiz Valencia

Senior Fullstack Engineer

9+ years building end-to-end applications — from scalable APIs and cloud infrastructure to modern, responsive frontends. I turn complex requirements into clean, maintainable software.

About Me

I'm a senior software engineer with 9+ years of experience designing and building production systems across diverse industries. I work across the entire stack — from backend architecture (APIs, databases, distributed systems) to frontend development (Angular, React/Next.js) — delivering complete solutions end to end.

9+
Years of Experience
5
Live Projects
8
Languages & Frameworks
3
Cloud Platforms

Core Focus

Full-Stack Architecture

Designing and delivering complete applications — API contracts, data models, frontend interfaces, and everything in between.

Backend Systems

REST APIs, relational databases, async processing, and distributed services with Python, Go, and C#.

Frontend Development

Building responsive, accessible interfaces with Angular, React/Next.js, TypeScript, and modern CSS frameworks.

Cloud & Infrastructure

Deploying and managing services on AWS, Google Cloud, and bare-metal servers with Docker and Nginx.

Event-Driven Design

Asynchronous pipelines with message streams, consumer groups, idempotent handlers, and full traceability.

DevOps & CI/CD

Automated builds, testing pipelines, containerized deployments, and infrastructure as code.

What Sets Me Apart

End-to-End Ownership

From architecture decisions to production deployment — I own the full lifecycle.

Clean, Justified Code

Every technical decision is deliberate, documented, and built to last.

Startup & Enterprise

Adaptable to fast-moving startups and structured enterprise environments alike.

Pragmatic Engineering

Solve the real problem. No over-engineering, no unnecessary abstractions.

Projects

Real-world demonstrative projects with serious architecture, clean code, and live deployments. Each one showcases different aspects of full-stack engineering.

NexusCRM

Live

Multi-tenant CRM with full-stack architecture

A lightweight multi-tenant CRM demonstrating SaaS architecture with JWT auth, role-based permissions, and a pipeline-driven sales workflow.

  • Multi-tenant data isolation via organization_id
  • JWT authentication with access/refresh tokens
  • Role-based access control (Owner, Admin, Sales Rep, Viewer)
FastAPIAngularPostgreSQLRedisSQLAlchemyJWTDocker

Event-Driven Onboarding

Live

Asynchronous processing with Go and Redis Streams

A service demonstrating event-driven architecture using Go and Redis Streams. Handles user onboarding through a chain of decoupled workers.

  • Redis Streams consumer groups for reliable processing
  • Correlation IDs for end-to-end traceability
  • Idempotent event handlers with retry logic
GoRedis StreamsPostgreSQLDocker
Source Code

Semantic Search API

Live

Document intelligence with local embeddings

An API for uploading documents, processing them into chunks, generating embeddings with a local model, and performing semantic similarity search.

  • Local embeddings with all-MiniLM-L6-v2 (zero API cost)
  • Chunking pipeline with configurable overlap
  • PDF and plain text document support
FastAPIsentence-transformersChromaDBPostgreSQLDocker
Source Code

Skills & Stack

Backend

PythonGoC#FastAPIDjango.NET

Frontend

AngularReactNext.jsTypeScriptTailwind CSS

Databases

PostgreSQLMongoDBRedisSQLAlchemyChromaDB

Cloud & DevOps

AWSGoogle CloudDockerGitHub ActionsNginxLinux

Architecture

REST API DesignMulti-tenancyEvent-DrivenMicroservicesSOLID

Messaging & Async

Redis StreamsBackground WorkersPub/Sub

Testing & Quality

pytestJestIntegration TestsCI/CD

AI & Search

Sentence TransformersEmbeddingsSemantic SearchChromaDB

Get in Touch

Interested in working together? Feel free to reach out through the form below or connect via social links.

Connect

Location

Remote — Open to remote opportunities worldwide