Sr Fullstack Typescript & Next.js

Description

Workana is the largest remote work platform for talents in Latin America.
Our segment Workana Premium focuses on matching the most exceptional professionals with leading and innovative companies around the globe. Enjoy competitive compensation, dedicated support, and the flexibility of remote work within a dynamic environment that fosters collaboration and professional advancement.

We are proud to present you with the following opportunity:

About Our Client

NeoMarketing.ai is a pre-seed AI startup that is redefining how companies optimize their web content for conversions.
They have developed a validated MVP that uses AI-driven multivariate testing at the edge to automatically optimize website content, combining LLMs, distributed systems, and Bayesian experimentation frameworks.

Role Overview

Position: Senior Full-Stack Engineer (TypeScript / AI)
Type: Freelance / Contractor (with potential for full-time transition)
Location: Remote (US time zones preferred for overlap)
Start Date: Immediate 

NeoMarketing.ai is looking for a Senior Full-Stack Engineer with strong expertise in TypeScript, Next.js and modern web architecture to help productionize their MVP and scale the platform.
You will work closely with the CTO to build and maintain distributed systems that combine edge computing, AI integrations, and real-time experimentation — focusing on reliability, scalability, and clean architecture.

Responsibilities

• Design, build, and maintain backend services using Next.js, tRPC, and Prisma.
• Develop and manage Cloudflare Workers for high-performance edge computing.
• Implement and optimize a Chrome extension and client-side SDK for content tracking and experimentation.
• Integrate LLMs (Claude, OpenRouter) for AI-driven workflows and real-time decision-making.
• Ensure type-safe, test-driven development using Vitest, Playwright, and Zod.
• Implement observability using OpenTelemetry and ClickHouse to monitor distributed systems.
• Collaborate with the CTO on architectural decisions and system design.
• Write clean, maintainable, and well-tested code following TDD and hexagonal architecture principles.
  
  

Requirements

• 5+ years of full-stack development experience, with at least 3 years working with TypeScript.
• Deep understanding of type-level programming, const generics, and branded types.
• Proven experience applying TDD (Test-Driven Development) rigorously in production environments.
• Experience building systems using Next.js, Prisma, and PostgreSQL.
• Understanding of clean architecture, dependency inversion, and domain-driven design.
• Hands-on experience with distributed systems, observability, and streaming architectures.
• Excellent attention to detail and ability to work independently in a remote environment.

Bonus Skills

• Familiarity with A/B testing, Bayesian experimentation, or marketing analytics.
• Experience integrating AI/LLM systems, Chrome extensions, or edge computing.
• Knowledge of ClickHouse, OpenTelemetry, or distributed tracing tools.
• Experience with modern React (server components, streaming SSR).

Tech Stack

• Frontend: Next.js, React, TypeScript
• Backend: Node.js, tRPC, Prisma, PostgreSQL
• Infrastructure: Cloudflare Workers, OpenRouter, ClickHouse, OpenTelemetry
• Testing: Vitest, Playwright

• Competitive compensation in USD.

• Fully remote work.
• Flexible schedule and collaborative work environment.