Senior Full Stack Engineer — Remote AI-Driven SaaS

Scalepex; United States; Remote; USD 140,000 - 190,000; Full time

Job summary

Scalepex is seeking a Senior Full Stack Engineer to join a fast-growing B2B SaaS startup building a modern multi-tenant platform that automates financial and operational workflows.

You will own core platform development, backend architecture, database design, integrations, and platform scalability in an AI-native engineering environment, leveraging modern AI coding tools to deliver high-quality software quickly.

Qualifications

• 5+ years of Full Stack or Backend software development experience.
• Strong knowledge of TypeScript and JavaScript.
• Expert Node.js experience.
• Experience with Next.js (App Router).
• Advanced PostgreSQL knowledge: schema design, raw SQL, migrations.
• Experience using Prisma ORM (or similar ORM).
• Experience building scalable SaaS applications and multi-tenant architecture.
• Experience building REST APIs and OAuth 2.0 integrations.

Responsibilities

• Design, develop, and maintain scalable backend services using Node.js and TypeScript.
• Own PostgreSQL database architecture, schema design, migrations, and performance optimization.
• Build and maintain REST APIs, OAuth integrations, and third-party platform connections.
• Develop and improve multi-tenant SaaS infrastructure.
• Create reliable background jobs, schedulers, and asynchronous workflows.
• Write automated unit and end-to-end tests.
• Audit existing systems and propose scalable technical solutions.
• Improve application reliability, performance, and security.

Skills

TypeScript

JavaScript

Node.js

Next.js

Multi-tenant architecture

REST APIs

OAuth 2.0

Testing

Git workflows

English communication

Tools

Prisma ORM

Playwright

Puppeteer

BullMQ

PgBoss

Nginx

Job description

Scalepex is seeking a Senior Full Stack Engineer to join a fast-growing B2B SaaS startup building a modern multi-tenant platform that automates financial and operational workflows.

You will own core platform development, backend architecture, database design, integrations, and platform scalability in an AI-native engineering environment, leveraging modern AI coding tools to deliver high-quality software quickly.