= Frequently Asked Questions

These are a list of unsorted, commonly asked questions and answers.

Please feel free to add items to link:https://github.com/embassy-rs/embassy/edit/main/docs/modules/ROOT/pages/faq.adoc[this page], especially if someone in the chat answered a question for you!

== Missing main macro

If you see an error like this:

[source,rust]
---
#[embassy_executor::main]
|                   ^^^^ could not find `main` in `embassy_executor`
---

You are likely missing some features of the `embassy-executor` crate.

For Cortex-M targets, consider making sure that ALL of the following features are active in your `Cargo.toml` for the `embassy-executor` crate:

* `arch-cortex-m`
* `executor-thread`
* `nightly`

For Xtensa ESP32, consider using the executors and `#[main]` macro provided by your appropriate link:https://crates.io/crates/esp-hal-common[HAL crate].