Changing tempd mid beat

I am new to the beatbuddy. Going to use this with a brass quintet. I need the ability to vary tempo slightly as the beat is continuing to play. I have found this arduino build that looks like exactly what I am wanting. But I am not able to build it. Is there a pedal on the market currently that would allow me to do the same thing. It would be find if it was a push button pedal I just need something that would be hands free. Thanks for any ideas!

If you have another device that can more easily vary tempo and send out MIDI clock signal then the Beatbuddy can sync to that.

Do you have an iPad or mobile device you can connect via MIDI? If so a suitable app will also allow you to send MIDI increment and decrement commands and set specific tempos (I use bandhelper MIDI presets for this amongst other things). I’ve not found anything perfect to app to give a simple tempo slider,but it can be done with free Yamaha fader app and two separate controls.

Apparently the new firmware out later in the year will support being able to do this via MIDI controller and expression pedal as that will be a capability enabled via the singular sounds own MIDI Maestro product (available to preorder). Something like a Morningstar MC6 would allow you to control via pedal I believe. MC6 also takes two expression pedals, so one could control tempo and another volume.