# How does the Simulator work?
**URL:** https://forum.xod.io/t/how-does-the-simulator-work/2528
**Category:** Uncategorized
**Created:** [August 26, 2019, 2:19pm UTC](https://forum.xod.io/t/how-does-the-simulator-work/2528 "2019-08-26T14:19:35Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@vcbz](https://forum.xod.io/u/vcbz)
#### Post date: [August 26, 2019, 2:19pm UTC](https://forum.xod.io/t/how-does-the-simulator-work/2528/1 "2019-08-26T14:19:35Z")
Hi guys, I would like to check how the simulator works. which source files should I read first to understand how its being called and updating the values on the xod-client. Im still a little clueless since the repository has a lot of different modules.
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### Author:  [@nkrkv](https://forum.xod.io/u/nkrkv)
#### Post date: [August 28, 2019, 12:14pm UTC](https://forum.xod.io/t/how-does-the-simulator-work/2528/2 "2019-08-28T12:14:58Z")
Hello! The simulator works as follows:
- The program is transpiled to C++ (the `xod-arduino` package)
- The resulting code is sent to the XOD cloud compiler service (`xod-cloud-compile`)
- The service compiles it using Emscripten and sends WASM-binary back
- The binary is being run in a sandbox (`xod-client-electron`)
- The binary sends debug protocol lines as any physical Arduino would
- XOD IDE parses the messages (`xod-client`) and reacts accordingly