New board

I really need to get around to writing this up properly, but thought I'd post some pics to encourage me to start documenting progress.
I had been using a rak5010 for a project although I ended up making lots of hacks and improvements to the board, so thought I'd try to design and build my own....
This is the most complex build I've ever done and it's not going smoothly, but I'm still making progress and getting there.
When (if?) its finished and working I will have all the designs uploaded.
Initially I'm getting a custom app working on it, but I should be able to get an espruino build going too since it's similar to the rak5010.
Getting there, pics attached of the first board (green) that had a design flaw, second board (purple) first fully built board, finally running (but due to power fault first bg96 blown and removed 😠)

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Pity you can't caption or annotate pictures.
The board is similar to the rak5010, but includes a voltage convertor so has native 3.3v IO and exposed I2C, also connects more of the BG96 IO for both AT and GPS serial streams and uses a MAX17048 'fuel gauge' for useful/reliable battery state. I haven't included sensors since I think it's easier/better to hook those up with I2C (e.g. I found the on board temp sensor of the 5010 was pointless since it heated up with the board)
Exposed both the NRF and BG96 to USB, added a JTAG socket.

I've had to make two manual patches on the board, but have also just blown the BG96 🤦‍♂️
Will switch to a USBC connector, and currently using a TP4056 for the charger, but I'm considering switching to something more advanced since I definitely need to do another build and board update.
Also using a Holyiot-18010 NRF module, but wondering if there's a better choice for this.
(and lesson learned SOD523 diodes are the work of the devil, going to swap those on the next design.)

That's looking great! How are you soldering it - with a hotplate, or air?

I use the TP4056 on stuff here and it works well - I've never seen a reason to change it. I guess something that would support different voltage ranges (eg to allow you to charge off a solar panel safely/reliably) might be cool though.

Cheers Gordon, that was step zero of the project (also to document) - build a hotplate. 😁 The software could do with improving (I could never get the PID control working, so I just timed and hardcoded it!)
Oh ok, perhaps I'll stick with the TP4096, I saw comments that it wasn't a good choice when you have an attached load so I was considering the TI BQ21040 instead which also has a wider range.

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Since I wanted to make sure it all worked I popped on a (cheaper, sacrificial) BG95 to test... and it only flipping well works, gets GPS satellites and connects to a mobile network! I am astounded and chuffed. This was the most complex thing I've ever designed and worked on.
If anyone wants more (longwinded rambling) details I've got another rambling write up - blog link.
I haven't got around to it yet, but I'll also upload the pcb layout and design files, probably this weekend.

Latest full build working like a charm. Got a board.js file setup and running Espruino! 👍
(haven't had time to check everything works, but I can talk to the battery monitor and the screen)
Espruino rocks!

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Looks pretty neat!