The challenge

Our client needed to track temperature and humidity at hundreds of points spread across dozens of geographically dispersed locations. What monitoring existed was fragmented: readings were captured by standalone loggers and manual spot checks, alerts were either too noisy to trust or arrived too late to act on, and compliance reporting was a manual, end-of-month scramble.

The operational cost of that fragmentation was real. Teams responded reactively — after conditions had already drifted out of range, after an excursion had already become a compliance problem. Leadership had no single, trustworthy view across the estate, and no way to tell a momentary sensor blip from the early signature of a genuine problem.

The brief was clear: before committing to a full-scale rollout, the client wanted a working proof of concept — one that demonstrated real-time visibility across a representative set of locations, surfaced problems before they became incidents, and put that intelligence in front of both site staff and central operations on whatever device they happened to be using.

The solution

ApplyLogic designed and delivered a complete, working proof of concept — end to end, from edge ingestion through to an AI insight layer and a cross-platform application — built and owned by a single engineering team. Crucially, this was no throwaway prototype: every layer was engineered on production-grade foundations, so the same architecture scales straight into a full deployment.

Reliable ingestion at the edge

Battery-powered LoRa sensors report temperature, humidity and location, transmitting over long ranges on minimal power — ideal for spread-out locations where mains power and reliable Wi-Fi can’t be assumed. Gateways relay those readings to a LoRaWAN network server, which forwards every uplink into the platform over MQTT using QoS 1 for at-least-once delivery. Connectivity in the field is rarely perfect, so durability was non-negotiable: persistent sessions mean the broker holds messages for a gateway that has briefly dropped offline, and when a link recovers, readings flush cleanly on reconnect — no silent data loss, no gaps in the audit trail.

A Go backend built for throughput and correctness

The processing layer is a set of stateless Go services responsible for normalising readings, evaluating rules, and routing alerts. Every message is processed idempotently, so redelivery never corrupts a sensor’s state or double-fires an alert — a discipline that matters enormously at the data volumes a full-scale rollout will reach. Storage is split to match each workload: high-volume, time-based telemetry lands in MongoDB, whose document model and time-series collections suit the relentless append-heavy stream of sensor data, while Neon Postgres holds the relational, transactional records behind the admin panel — sites, sensors, users, thresholds and compliance configuration — where structure and integrity matter most.

The AI layer

This is what moved the client from monitoring to prediction, and it works in two parts:

  • Anomaly detection. Rather than relying on static thresholds alone, the platform learns a normal baseline for each location and flags meaningful drift — a spot trending warmer day over day, or humidity creeping up well before any hard limit is breached. These are the early signatures of trouble that fixed thresholds miss entirely.
  • Plain-English insight. Raw anomalies are technical. We added an LLM-powered layer that translates them into clear summaries and recommended next actions, so a site manager with no technical background reads “The sensor in Zone 3 has been trending warmer with rising humidity — worth checking before it breaches limits” rather than a wall of numbers.

One app, every platform

The entire experience is delivered through a single Flutter codebase spanning iOS, Android and web. Because every reading carries a location, central operations get a live map of the whole estate in the browser, while site staff get real-time alerts and per-sensor detail on their phones. One codebase meant faster delivery, consistent behaviour everywhere, and a far lower cost of ongoing change.

Infrastructure

The platform runs on DigitalOcean with Caddy handling TLS and routing, and full observability through Prometheus and OpenTelemetry — so the system that watches the client’s estate is itself thoroughly watched.

What the proof of concept proved

Running across a representative set of locations, the PoC validated both the technology and the business case:

  • Earlier detection — developing problems were flagged ahead of any limit breach, showing how the platform shifts teams from reactive callouts to planned intervention.
  • Fewer excursions — on the pilot sites, temperature and humidity issues were caught and corrected early, well before they could cross compliance limits or cause real damage.
  • Automated compliance — the manual monthly reporting exercise was replaced by a continuous, exportable audit trail generated on demand.
  • Faster triage — plain-language insights let non-specialist staff act on the right alerts immediately, demonstrating how a full rollout would reserve specialist time for the issues that truly need it.

Why it worked

The technology mattered, but the difference was engineering judgement: choosing a messaging backbone that stays correct under real-world conditions, building idempotency in from day one, and resisting the temptation to bolt AI on as a gimmick. The anomaly detection and language model layers earn their place precisely because they sit on top of a foundation that is reliable, observable and built to scale.

Building an AI-Enabled Product?

ApplyLogic designs, builds and hardens solutions where AI does the heavy lifting — let's talk about yours

Get in Touch