XiaoBackpack — XIAO ESP32-C3 Mounting Case

XiaoBackpack is a compact, modular mounting case for the Seeed Studio XIAO ESP32-C3.

It was designed for small battery-powered ESP projects where I wanted to keep the wiring simple, avoid adding a separate external button, and still have a clean way to mount the board inside or behind another printed project.

The enclosure is made from two printed parts:

• Case — the main body with walls, XIAO mounting area, underside connectivity access, and the USB-C cutout.

• Lid — closes the enclosure and contains the flexible structure that presses the XIAO’s onboard BOOT button.

The BOOT button stays accessible through the lid and can be used as the main input for a project. In my use case, a short female-to-female Dupont jumper wire connects D9 / GPIO9 to D3, allowing the BOOT button to be used with the matching deep-sleep wake configuration—without adding or soldering an external button.

XiaoBackpack preserves the useful connectivity below the XIAO PCB:

• Compatible with male 2.54 mm Dupont headers soldered to the XIAO.

• Female Dupont connectors can remain plugged in while the board is installed.

• Battery wires can route through the enclosure opening.

• The supplied external antenna wire can route out through the back.

• Bottom-side wiring is easy to access while mounting the visible enclosure face outward.

• Displays, sensors, batteries, and other wiring can be hidden behind the panel, project, or enclosure that XiaoBackpack is attached to.

The mounting pattern is:

2 × Ø2.5 mm mounting holes 32 mm centre-to-centre

Case variants

Two case variants are included so you can choose between a cleaner button feel and a more mechanically secure lid.

Variant A is best if you want the cleanest possible button area. It is especially nice when the BOOT button will be pressed regularly.

Variant B is best if the device will be handled roughly, mounted permanently, or carried in a bag where you want the lid held on as securely as possible.

Lid variants

Each mounting version includes three lid options:

1.0 mm button 1.5 mm button 2.0 mm button

This dimension is the thickness of the flexible printed plastic that transfers your finger press to the XIAO’s onboard BOOT button.

The thicker lid options flex less easily, so they require a more deliberate press and make the enclosure feel more rigid. The thinner options are more comfortable if the button is used often.

This is a small enclosure, but it intentionally includes several combinations: two case styles × three button-thickness lids. Try a couple of options and choose the feel and mechanical security that best match your project.

Hardware required

• 1 × Seeed Studio XIAO ESP32-C3

• 1 × short female-to-female Dupont jumper wire

• Jumper connection: D9 → D3

• Variant A: M2 × 6 mm or longer screws (2 pcs.)

• Variant B: M2 × 14 mm or longer screws (2 pcs.)

• Optional: male 2.54 mm headers soldered to the XIAO for underside wiring

Notes

• The D9 (BOOT) → D3  jumper is used for the deep-sleep wake setup in the matching firmware.

• The jumper configuration should only be used with firmware designed for that wake method.

• Designed and tested for the Seeed Studio XIAO ESP32-C3 form factor.

• The enclosure was originally created for a compact smart timer (seen in example pictures), but it is intended as a reusable mounting platform for displays, sensors, controllers, data loggers, and other compact embedded projects.

• Type-C has integrated supports to get a cleaner port. Please remove supports using flush cutters / small knife. BE CAREFUL!

• Dimensions for mounting XiaoBackpack can be obtained from STEP files or front side technical drawing that is included.