Working with explorers or coin builds on a very small VPS can be a bit difficult, as you might run into memory limits, as most 5$ VPS often only have 1 GB RAM.
I’ve had issues building coins and setting up explorers and adding a swap file seems to help thing run smooth. Here’s how to add a 1 GB swap file on Ubuntu 16.04:
free #check if swap is 0
dd if=/dev/zero of=/var/swap.img bs=1024k count=1000
free #check if swap is 1024
That’s it. 1 GB swap added. Now your stuff should run (a bit more) smoothly.