For 100 gb that might grow to 1tb:

2x NVME drives, each 1tb in size. Buy pcie adapter as needed.

Buy used 256gb RAM server off eBay.

Install drives into server. Put all data on the nvme drives and all other files on regular drives.

Everything will fit in ram after the data is touched the first time after each boot. Can't get faster than that, usually.

Create user accounts for each user, set up git etc. for code storage and to encourage reuse.