Senior Full-Stack Developer (Backend-Leaning Builder)

Hammerjack Pty Ltd; Philippines; On-site; PHP 1,200,000 - 2,000,000; Full time

Job summary

Hammerjack Pty Ltd in the Philippines seeks a Senior Full-Stack Developer (Backend Leaning Lead Builder) to own backend architecture, system design, and data modeling while contributing across the stack to rebuild and scale a modern B2B/B2B2C platform for sports mental performance.

The role emphasizes building robust RESTful APIs, RBAC, AI integrations with Claude/OAI, and end-to-end ownership from backend to frontend integration, ensuring performance and security as the product scales.

Qualifications

• 4+ years of senior software engineering experience.
• Strong backend and system design mindset.
• Full-stack capabilities across React, TS, Node.js.
• Experience with AI API integrations (OpenAI, Anthropic).
• Proven experience shipping production-grade apps.
• Excellent English communication.

Responsibilities

• Architect backend systems and platform structure.
• Design database schemas, relationships, and migrations.
• Build, maintain, and optimize RESTful APIs.
• Implement authentication and RBAC systems.
• Handle integrations, background jobs, and webhooks.
• Manage file/media storage (images, audio, video).
• Integrate AI APIs into workflows.
• Ensure system scalability, performance, and security.
• Support frontend and mobile integration.

Skills

Senior software engineer

Backend design mindset

Full-stack development

React & React Native

TypeScript

Node.js

RESTful APIs

PostgreSQL design

AI integrations

Claude Code

English communication

Tools

OpenAI API

Anthropic Claude

Job description

Senior Full-Stack Developer (Backend-Leaning Lead Builder)

We are hiring for a Full-stack developer Backend Leaning Lead Builder who will take ownership of backend architecture, system design, and data modeling while still contributing across the stack and to help us rebuild and scale a modern B2B/B2B2C sports mental performance platform.

Duties & Responsibilities:

• Architect backend systems and overall platform structure
• Design database schemas, relationships, and migrations
• Build, maintain, and optimize RESTful APIs
• Implement authentication and role-based access control (RBAC) systems
• Handle integrations, background jobs, and webhooks
• Manage file/media storage (images, audio, video)
• Integrate AI APIs (OpenAI / Anthropic) into workflows; Claude Code
• Ensure system scalability, performance, and security
• Support frontend and mobile integration

Qualifications:

• 4+ years Senior software engineering experience
• Strong backend/system design mindset, program/pursuit builder
• Full-stack capability, including React, React Native, TypeScript, Node.js, REST APIs, Database design (PostgreSQL or similar) AI API integrations (OpenAI, Anthropic)
• Experience using AI-powered tools - Claude Code
• Proven experience shipping production-grade applications
• Ability to build and own features end-to-end
• Strong problem-solving skills with attention to edge cases, scalability and architecture
• Excellent communication skills in English