I’d like tipis for/against doing this without an external WiFi router
inbetween. I want to be as secure as possible and use it at home
to let my WiFi-using entities use the speed, but specifically also
for cell phone roaming. Also, is direct USB tethering OUT doable?
URLs for good docs appreciated 
type or paste code here
USB tethering (and bluetooth) are both possible, but not officially implemented.
If you are good with iptables (I am not anymore) it is pretty easy to pipe that data from the cellular interface to the USB or BT interface, you will also need to hand set IP addresses or set up a DHCP. You will find all kinds of tutorials on how to do this on the openwrt forums. https://openwrt.org/ I think if you made an account they would also be open to helping you make this work as the network environments are very similar and they are all about networking setups far more complicated than this.
The important thing to remember is that the bluetooth, wifi, USB, and cellular modem as well as other interfaces are interchangeable when looking at tutorials like these,you are just connecting them together like Legos. There was a tuturial over at Mobian, but they deleted most of the really useful tutorials from their wiki about three years ago.
There is also the work done on previous mobile linux devices like here, using this below I once had a partly working tethering environment over both BT and USB.
WiFi is as secure as you make it. Use the latest possible WiFi security and with a strong meaningless passphrase.
However whether WiFi hotspot is even possible depends on what WiFi card is installed in the Librem 14.
And I would forget about Bluetooth as an option. You don’t share “fast fiber” over Bluetooth.
Thank you biketool
I think what I want is hostapd, but not so massive 
I am running pureos, a debian based os
uname -rvm
5.10.0-38-amd64 #1 SMP Debian 5.10.249-1 (2026-02-10) x86_64
Operating System: PureOS 10 (Byzantium)
Kernel: Linux 5.10.0-38-amd64
Architecture: x86-64
I did sudo apt-get source hostapd into a directory to see what
the various README* said. Heavy reading, and heavy package, and dependencies:
du -hs hapd/*
23M hapd/wpa-2.9.0
100K hapd/wpa_2.9.0-21+deb11u2.debian.tar.xz
4,0K hapd/wpa_2.9.0-21+deb11u2.dsc
2,3M hapd/wpa_2.9.0.orig.tar.xz
(my emacs reflexes are killing me here :-P )
Anyway, thanks all!
(Below is link if first found looking for tethering sharing laptop fiber by wifi).
[https://askubuntu.com/questions/105217/how-do-i-create-a-non-adhoc-wifi-hotspot](https://askubuntu.com/questions/105217/how-do-i-create-a-non-adhoc-wifi-hotspot)the previous post was just about getting the the tethering working not overall speed, for that you would be best served searching out a openwrt flashable router. I recall seeing that the bus speed on the librem5 is not great overall though the bottleneck mentioned might be the modem card vs a USB-eth adapter which bottlenecks at the USB interface level. I can say that if you intend on including a router level VPN to invest in the CPU and memory in the router to not bottleneck speed there.(bottleneck=narrow point causing network loss)
As for the link you posted I think(I dont have the adapter nearby to test) the Phosh WiFi settings hotspot will take ANY active internet connection and route that through the wifi hotspot automagically, try turning off cellular data with the USB adapter connected and working(check some websites on a browser) then run the Wifi hotspot and tell us what speeds you get running speedtest from a tethered-connected computer.
This topic is Librem 14 though.
Yup… in the title…..
There should be plenty of power for everything including the VPN example; in fact this would be an ideal machine if you wanted to include that. Openwrt forums are what you will want to study though; so many examples of the iptables routing or look for the phosh packages used for the librem 5.
Your link is good too but the link I posted is closer to how I have done it in the past for openwrt routers and my old Nokia N900(linux) phone.