---
title: "Integration notes"
source_url: https://dev.digicert.com/trustcore-sdk/nanomqtt/integration-notes.html
---

Use the steps below as a general guide for binding NanoMQTT to either *clear-text TCP* or *TLS*.

## Switch transports in one line

```c
/* TLS (port 8883, NanoSSL already negotiated) */
MQTT_setTransportSSL(conn, ssl);

/* Plain TCP (port 1883) */
MQTT_setTransportTCP(conn, socketFd);
```


> **Info**
>
> Call one of the above **before** `MQTT_negotiateConnection()`. The rest of the API is identical.


## Build note

The socket helpers are always available. Enable the asynchronous wrapper only if you need it:

```bash
# static or CMake: add the macro
-D__ENABLE_MQTT_ASYNC_CLIENT__
# helper script
./build_mqtt_client.sh --async
```

## Quick validation

1. **Pass 1 - TCP** Bind with `MQTT_setTransportTCP`; connect to port 1883 and publish a test message.
2. **Pass 2 - TLS** Switch to `MQTT_setTransportSSL`, port 8883, and supply `--ssl_ca_file <bundle>`. The payload and topic should be identical.

A match between the two passes confirms both the NanoSSL handshake and the MQTT control flow.