Prison Architect is an indie game developed by Introversion Software. The main focus of the game is to build a prison, fufill grants, and run the prison in however you like. Prison Architect is currently in Alpha and has currently sold 67,438 copies.  Prison Architect is available on Steam for various prices for different versions. These versions are: Prison Architect Standard, USD 29.99, Prison Architect Aficionado, USD 34.99, Prison Architect Introversioner, USD 39.99, and Prison Architect Name in Game, USD 49.99. 
Prison Architect has many features, such as federal grants, security systems, guards, and random prisoner actions (such as smuggling contraband and starting riots). One important aspect of Prison Architect is balancing the amount of money spent for employing Staff versus earning money from taking care of prisoners. This daily profit is called cashflow and determines how much money the prison earns per day. The amount of money earned is determined by the amount of prisoners times (a number) minus daily spending from employing Staff. Any money you spend is not counted, and neither are federal grants which will grant you money.
Main Article: Version History Prison Architect is currently in Alpha 33.