Platform Architect & Backend Lead

About the Role We are building a multi-tenant, hardware-agnostic IoT platform from the ground up. We need a senior engineer who can design the system architecture in the morning and write production backend code in the afternoon. This is not an architecture-only role and not a coding-only role — it is both, simultaneously, in a fast-moving early-stage environment. You will also own cloud infrastructure as interim DevOps until we scale. The Ideal Candidate You have built IoT backend platforms before — not just used them. You understand the hard problems: device auth at scale, MQTT broker design, time-series ingestion performance, multi-tenant data isolation, and real-time delivery to web clients. You are comfortable making architectural decisions autonomously, documenting them clearly, and standing by them. You work remotely with discipline — you flag risks before they become problems. Key Responsibilities Platform Architecture Design the full end-to-end IoT platform architecture: device connectivity layer → MQTT/protocol ingestion → stream processing → time-series storage → REST/GraphQL API layer → real-time WebSocket delivery Define the multi-tenant data model: strict data isolation between customers, tenant-scoped API tokens, row-level security Design the device lifecycle system: provisioning, X.509/JWT authentication, device registry, status tracking, decommissioning Architect the protocol abstraction layer so MQTT, Modbus, OPC-UA, CoAP, and HTTP devices all normalise to the same internal data model Design a configurable rule engine: event-condition-action rules for alerts, automations, and integrations — no code required from customers Plan OTA firmware update management: secure delivery, versioning, rollback, fleet orchestration Write Architecture Decision Records (ADRs) for every major technical choice — nothing undocumented Design the scaling path from 100 devices (pilot) to 500,000+ (production) without structural rework Backend Development Build core platform services from scratch: device management, telemetry ingestion, rule engine, notification/alerting, OTA update, multi-tenant API gateway Develop REST and GraphQL APIs with full OpenAPI specification — version-controlled from Day 1 Implement WebSocket and SSE endpoints for real-time telemetry delivery to web and mobile clients Build device command-and-control with acknowledgement, retry logic, and timeout handling Implement device shadow service: last-known state of every device accessible even when offline Write unit, integration, and load tests — no service reaches staging without test coverage Own service reliability: SLO definitions, alerting runbooks, on-call incident response Cloud Infrastructure (Interim) Provision and manage all AWS environments (dev, staging, production) using Terraform — no click-ops Configure AWS IoT Core: MQTT endpoint, topic namespace, rules engine, certificate management Set up CI/CD pipelines via GitHub Actions for all backend services Configure CloudWatch monitoring, log aggregation, and automated health alerts Manage IAM for all team members — least-privilege access, no shared credentials Hand off infrastructure fully documented when a DevOps engineer joins in Phase 2