Background: I self-taught C++ in high school and majored in computer engineering in undergrad, so I am not totally ignorant of programming. However, I have never written any code to implement an automated trading system with APIs. Question: I am looking for any learning resource that can help me get started with writing an ATS, preferably in C++. If there is any simple "example code" out there, that would be ideal since I think it's the fastest and easiest way to learn. From browsing this forum, it seems like APIs are just an interface to connect to a platform(Laser, Sterling Pro, Anvil...). So do people just use C++ or VB to write their own program to make function calls to the API? Does that mean you can just use any general purpose IDE for your preferred language? There are some commercial software(NT, OQ, RE) that can do automation. If you write your own ATS in C++ or VB, are you essentially writing your own software package that does what those commercial ones do with more customization? If that's the case, it would seem like a huge project. Can anyone provide an estimate of the time required to implement an ATS from scratch for a reasonable programmer? I am new to this so some of my question may not make sense. Feel free to correct me and any help/advice is highly appreciated.