Principal AI Email App Architect & Tech Lead

Bjak; Indonesia; On-site; IDR 1,200,000,000 - 2,100,000,000; Full time

Job summary

Bjak is seeking a Principal Software Engineer for its AI Email App, responsible for shaping the architecture across backend services, APIs, and client applications while mentoring a small team of senior engineers. This hands-on leadership role emphasizes rapid delivery, production readiness, and strong collaboration with ML leadership.

This role requires building reliable AI-powered workflows, designing robust APIs, and balancing latency, cost, security, and user experience to scale with the

Qualifications

• Significant experience leading application or product engineering for complex systems.
• Hands-on background building production-ready backend systems.
• Experience shipping AI-powered products integrated with ML/LLM capabilities.
• Strong technical judgment for decisions with incomplete information.
• Comfort working across backend and client platforms with deep expertise in at least one.
• Bias toward ownership, shipping, and learning from real-world usage.
• High standards for code quality, reliability, and fundamentals.

Responsibilities

• Own the application engineering strategy across backend, mobile, and desktop.
• Design reliable AI-powered workflows with state management and retries.
• Build APIs connecting AI systems to real-world products.
• Lead a small senior engineering team with code & design reviews.
• Balance latency, cost, security, and user experience.
• Establish production foundations: observability, testing, and ops.
• Collaborate with ML leadership to ship robust features.
• Move quickly while keeping architecture simple and scalable.

Skills

Leadership

Backend systems

Architecture

AI/ML integration

Code reviews

Tools

API design

Observability tools

Job description

Bjak is seeking a Principal Software Engineer for its AI Email App, responsible for shaping the architecture across backend services, APIs, and client applications while mentoring a small team of senior engineers. This hands-on leadership role emphasizes rapid delivery, production readiness, and strong collaboration with ML leadership.

This role requires building reliable AI-powered workflows, designing robust APIs, and balancing latency, cost, security, and user experience to scale with the