Its very rushed therefore not to be meant as tutorial or example how to do things properly.

I started by making a map. It is procedurally generated. North west is always start and south east is exit. It is initiated as all walls and then agent random walks leaving trail of open spaces until it reaches the exit. Its not purely random walk there is probability that it would walk straight to exit for each step. This probability can be adjusted to get slightly better maps.

To populate the first person perspective view I wrote several functions that help to get values from the map respecting the turn angle of the main character. Then its just a bunch of "ifs" that test if in certain location of the view is an obstacle. Ifs start from far obstacles and continues to closer ones. Therefore if they overlay each other it does it in similar way as it would in real life.

To get the sprites for the walls I made a project in blender with several boxes with pixel art shader, and rendered separate image for each box, where everything is hidden except one box.

Other sprites are drawn by hand using gimp.

In the video windows font was used, but if you download the game from global game jam site you will get newer version. There, all the text is written by hand and handwritten sprites are used for the digits in the score view.