Principal Architect – Golang / Node.js

About the role

Circles is seeking a Principal Architect to lead the technical vision for the povo platform serving KDDI’s digital telecommunications services in Japan. The role combines strategic architecture leadership with hands‑on engineering across a large‑scale, cloud‑native environment.

Key responsibilities

• Define and evolve the overall technology and architecture vision for the povo platform.
• Lead end‑to‑end architecture for complex, cross‑domain initiatives such as identity, billing, provisioning, and SIM/eSIM.
• Drive platform modernization, technical‑debt reduction, and adoption of reusable capabilities.
• Own architectural engagement from early requirements through production readiness and guide stakeholder discussions with product, engineering, SRE and KDDI partners.

Required profile

• 14+ years of software engineering experience with significant architecture and technical leadership responsibilities.
• Proven track record designing large‑scale production systems and influencing multiple engineering teams without direct reporting authority.
• Excellent stakeholder management and communication skills, able to present trade‑offs and recommendations to both technical and non‑technical audiences.

Required skills

• Strong hands‑on experience with Go and/or Node.js.
• Deep expertise in distributed systems, microservices, API design, asynchronous processing, messaging and event‑driven architectures.
• Solid knowledge of relational and NoSQL databases, Redis, and distributed data consistency.
• Experience with cloud‑native architectures, Kubernetes, CI/CD pipelines and AWS (or equivalent cloud platform).

What we offer

• Significant influence over the architecture and long‑term evolution of a telecom‑scale platform.
• Opportunity to shape technical strategy across multiple business and engineering domains.
• Close collaboration with senior Circles and KDDI technology stakeholders.
• High autonomy, visibility and the chance to combine strategic leadership with continued hands‑on engineering.