domain-iot

What the source does

• FilesystemNone observedNo reads or writes in the source
• NetworkNone observedNo outbound calls in the source
• ShellNone observedNo commands run in the source
• DependenciesPinnedNothing floats
• SecretsNone foundNo keys in source

Five audit layers

Gates applied: no behavioural pass, no license.

Audit 0.4.1 · source sha f4ff8c82542d · 26 Oct 2026Report an issue or request a re-scan

• Publisherzhanghandong GitHub organizationOwner of the repository this skill is read from
• Source folderzhanghandong/rust-skills/skills/domain-iotThe exact folder we audited
• LicenceNot declaredAs the repository states it
• Commit pinned for this verdictf4ff8c82542dA new audit runs when the source changes
• Repository statusNot archivedLast push 63 days ago
• Sandboxed runNot runSkills are read, not executed; layer L4 is skipped

Its description: Use when building IoT apps. Keywords: IoT, Internet of Things, sensor, MQTT, device, edge computing, telemetry, actuator, smart home, gateway, protocol, 物联网, 传感器, 边缘计算, 智能家居

---
name: domain-iot
description: "Use when building IoT apps. Keywords: IoT, Internet of Things, sensor, MQTT, device, edge computing, telemetry, actuator, smart home, gateway, protocol, 物联网, 传感器, 边缘计算, 智能家居"
user-invocable: false
---

# IoT Domain

> **Layer 3: Domain Constraints**

## Domain Constraints → Design Implications

| Domain Rule | Design Constraint | Rust Implication |
|-------------|-------------------|------------------|
| Unreliable network | Offline-first | Local buffering |
| Power constraints | Efficient code | Sleep modes, minimal alloc |
| Resource limits | Small footprint | no_std where needed |
| Security | Encrypted comms | TLS, signed firmware |
| Reliability | Self-recovery | Watchdog, error handling |
| OTA updates | Safe upgrades | Rollback capability |

---

## Critical Constraints

### Network Unreliability

```
RULE: Network can fail at any time
WHY: Wireless, remote locations
RUST: Local queue, retry with backoff
```

### Power Management

```
RULE: Minimize power consumption
WHY: Battery life, energy costs
RUST: Sleep modes, efficient algorithms
```

### Device Security

```
RULE: All communication encrypted
WHY: Physical access possible
RUST: TLS, signed messages
```

---

## Trace Down ↓

From constraints to design (Layer 2):

```
"Need offline-first design"
    ↓ m12-lifecycle: Local buffer with persistence
    ↓ m13-domain-error: Retry with backoff

"Need power efficiency"
    ↓ domain-embedded: no_std patterns
    ↓ m10-performance: Minimal allocations

"Need reliable messaging"
    ↓ m07-concurrency: Async with timeout
    ↓ MQTT: QoS levels
```

---

## Environment Comparison

| Environment | Stack | Crates |
|-------------|-------|--------|
| Linux gateway | tokio + std | rumqttc, reqwest |
| MCU device | embassy + no_std | embedded-hal |
| Hybrid | Split workloads | Both |

## Key Crates

| Purpose | Crate |
|---------|-------|
| MQTT (std) | rumqttc, paho-mqtt |
| Embedded | embedded-hal, embassy |
| Async (std) | tokio |
| Async (no_std) | embassy |
| Logging (no_std) | defmt |
| Logging (std) | tracing |

## Design Patterns

| Pattern | Purpose | Implementation |
|---------|---------|----------------|
| Pub/Sub | Device comms | MQTT topics |
| Edge compute | Local processing | Filter before upload |
| OTA updates | Firmware upgrade | Signed + rollback |
| Power mgmt | Battery life | Sleep + wake events |
| Store & forward | Network reliability | Local queue |

## Code Pattern: MQTT Client

```rust
use rumqttc::{AsyncClient, MqttOptions, QoS};

async fn run_mqtt() -> anyhow::Result<()> {
    let mut options = MqttOptions::new("device-1", "broker.example.com", 1883);
    options.set_keep_alive(Duration::from_secs(30));

    let (client, mut eventloop) = AsyncClient::new(options, 10);

    // Subscribe to commands
    client.subscribe("devices/device-1/commands", QoS::AtLeastOnce).await?;

    // Publish telemetry
    tokio::spawn(async move {
        loop {
            let data = read_sensor().await;
            client.publish("devices/device-1/telemetry", QoS::AtLeastOnce, false, data).await.ok();
            tokio::time::sleep(Duration::from_secs(60)).await;
        }
    });

    // Process events
    loop {
        match eventloop.poll().await {
            Ok(event) => handle_event(event).await,
            Err(e) => {
                tracing::error!("MQTT error: {}", e);
                tokio::time::sleep(Duration::from_secs(5)).await;
            }
        }
    }
}
```

---

## Common Mistakes

| Mistake | Domain Violation | Fix |
|---------|-----------------|-----|
| No retry logic | Lost data | Exponential backoff |
| Always-on radio | Battery drain | Sleep between sends |
| Unencrypted MQTT | Security risk | TLS |
| No local buffer | Network outage = data loss | Persist locally |

---

## Trace to Layer 1

| Constraint | Layer 2 Pattern | Layer 1 Implementation |
|------------|-----------------|------------------------|
| Offline-first | Store & forward | Local queue + flush |
| Power efficiency | Sleep patterns | Timer-based wake |
| Network reliability | Retry | tokio-retry, backoff |
| Security | TLS | rustls, native-tls |

---

## Related Skills

| When | See |
|------|-----|
| Embedded patterns | domain-embedded |
| Async patterns | m07-concurrency |
| Error recovery | m13-domain-error |
| Performance | m10-performance |

Excerpt, first 4,360 characters of SKILL.md, verbatim from the audited commit. It is text from someone else’s repository, quoted so you can judge it before your agent reads it.

git clone https://github.com/zhanghandong/rust-skills
git -C rust-skills checkout f4ff8c82542d

Works in

1. 2026-10-26
   ✓SAFE B 89 / 100

   first audit · source f4ff8c82542d

Questions about domain-iot

• github.com/zhanghandong/rust-skills/tree/main/skills/domain-iot — the audited source at commit f4ff8c82542d and every finding aboveObserved · 26 Oct 2026

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