The engine I used to make Rush to Adventure didn't support Steam Achievements when I released the game. But a plugin was released some time ago that seems to do the trick.
This image shows some of the artwork I've made for the achievements. I intend to have more that twice this many when I finally release the update. Implementing them is a slow process because I have limited time to work on it each week.
Figuring out what to make achievements from and how to implement them. Making artwork. Setting them up according to Steams specifications. And finally programming them in. It is quite the process but I am working on them! ːsteamhappyː
Update:
Finally got the plugin talking to the API today (3rd of April). Sadly multiple technical issues have led to this delay. The achievements shows up in Steam now but you still can't earn them in game. Wait for the new version to be released.