Tech Lead/Senior Software Architect (Remote: Vietnam)

Alongside partners with organizations to drive digital transformation and build high-performing tech teams. We're building a real-time facility navigation and asset-tracking platform for industrial and logistics sites — GPS/BLE-based positioning, live forklift and asset overlays, zone/dwell analytics, and a driver-facing mobile app, running on a distributed, actor-model backend, as well as an admin portal. The Role We're hiring a senior Tech Lead / Software Architect to own the technical direction of the platform's backend architecture, with a specific focus on its actor-model distributed system (built on Microsoft Orleans). Beyond architecture, this person leads the engineering team day-to-day: coordinating closely with the Project Manager on planning and delivery status, and joining client calls to speak to technical progress and tradeoffs. This is a fractional engagement — roughly half-time, spread across the full length of the project. Responsibilities — Architecture & Engineering • Own and evolve the architecture of a distributed, actor-model backend (Microsoft Orleans) handling realtime positioning and telemetry data at scale • Set technical direction for the .NET backend: API design, data pipelines, service boundaries • Design the path toward multi-node Orleans clustering as the platform scales • Review code and provide hands-on technical guidance to backend and full stack engineers • Identify and remediate security and architectural risk areas (authentication, data handling, system hardening) • Partner with data/telemetry and QA engineers on ingestion pipeline and analytics architecture decisions • Advise on CI/CD, staging environment, and release practices Responsibilities — Team Leadership & Communication • Act as engineering team lead: set priorities, unblock the team, and own technical quality across the engineering group • Coordinate closely with the Project Manager on sprint planning, delivery status, and risk/blocker escalation • Join client calls run by the project team, speaking directly to technical progress and tradeoffs when needed • Mentor other engineers, raising the technical bar across the team • 5+ years of professional software engineering experience, including senior/lead-level architecture responsibility • Hands-on experience with actor-model distributed systems (Microsoft Orleans strongly preferred; Akka or comparable frameworks considered) • Strong backend expertise in C#/.NET — API design, services, data pipelines at scale • Experience architecting systems that process realtime/streaming data (telemetry, sensor data, WebSockets) • Proven track record leading a small engineering team — code review, mentoring, setting technical direction • Experience working closely with a Project Manager on planning and delivery, including joining client calls to speak to technical topics • Strong written and spoken English — comfortable communicating with both engineers and non-technical stakeholders • Security-conscious architecture practices (authentication, PII handling, system hardening) Nice to Have • Experience with GPS/BLE positioning or realtime geospatial systems • Background in industrial, logistics, or IoT/telemetry domains • Experience designing for multi-node clustering / horizontal scaling • Cloud infrastructure experience (Azure preferred, given the .NET/Orleans stack) Remote work (Vietnam-based) Estimated project duration: 19 weeks Part-time schedule: 4 hours per day, aligned with Portugal business hours (WET/WEST) Freelance / Service Agreement Hourly Rate: 20$-25$