Here is a little insight into how I designed and mapped out the levels for the game. The playdate pulp engine works on a tile system, made up of 25x15 tiles, which I believe is similar to how the original Gameboy functioned. Only on playdate you have just two display colours to work with.

Because of this it made sense to plan out some of the levels on a grid system I had drawn out in Procreate. This way I could map out the mechanics, using colour-coded items on individual layers. When I needed to iterate on the design I could shift things around easily and play-test them mentally or by marking out the movement on the grid. 

When the levels were working I could use the image as a guide, first building the basic structure in black solid tiles and white unsolid tiles. Pulp works on a system of solid and non-solid tiles. Solid tiles cannot be walked through and form the walls or boundaries of play. Non-solid tiles form the basic environment, the rooms of the game.

Here are a couple of the level design images I created while developing the game.