describe the pi platfrom

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+Bill of materials:
+
+1) raspberry pi 3a+
+It's a smaller raspberry pi board.
+I went for a soc instead of a microcontroller so that I can have easy networking, and a remote terminal.
+It was also available from a local store and I like buying local.
+
+2) Waveshare 4.3inch capacitive touch display for Raspberry Pi, DSI Interface, 800x480
+It's the smallest DSI display I could find.
+I wanted to use DSI so that I didn't need extra extra power for an HDMI display.
+Using a DSI connector also has a lower footprint than using HDMI.
+I really wanted to keep this project as small as possible for some reason.
+
+3) Adafruit USB Type C Power Delivery Dummy Breakout - I2C or Fixed - HUSB238
+From experience a raspberry pi always complains about undervoltage.
+I thought that this could be fixed with USB-PD.
+Except the raspberry pi 3a+ doesn't have USD-PD, let alone a usb-c port.
+The Pi 4 has one, but I wanted a smaller footprint.
+So I got this board to connect to the power gpio pins of the pi.
+I set it to 5V-3A which is what the Pi wants at most.
+Though it sometimes still complains about too little voltage.
+Either my cabling has a voltage drop, or the display draws too much current.
+Maybe that's why DSI displays are less common for raspberry pis.
+Maybe this can be fixed by setting the voltage higher and using a buck converter to go back to 5V, but with more amps.
+Ah well, the pi works just a little slower on lower voltage which is acceptable.
+
+4) M2.5 and M3 nuts and bolts
+The raspberry pi mounts to the display with the supplied hardware, but the display mounts to the case with some longer M2.5 bolts.
+The case itself is put together with M3 screws and bolt.
+There are no heated inserts.
+Instead I embed nuts into the print by prism shaped leaving voids in screw holes, and pausing the printer in gcode to insert a nut.
+If the clearances are right the nut is secured in place while having some tolerance, and even supports the next overhang.
+You should hear the nuts rattle if you shake the part.
+It's pretty secure, as tightening the nut compresses the 3D printed wall that's surrounds the screw hole.
+I haven't used threaded inserts before, but I already prefer this.

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+The raspberry pi image runs wayland nowadays, so I had the pleasure of figuring this out.
+Next (on top?) of wayland the pi runs sddm. https://github.com/sddm/sddm/
+Sddm runs a desktop which consists of Cage running the gummi binary. https://github.com/cage-kiosk/cage
+The gummi binary is an openGL 2.1 application, because that's what the pi supports.
+The binary uses glfw and glad to get things working.
+
+I hope that by using cage I can run an another graphical application from within gummi, and later kill it.