How can I export a Postgres database?

Using pg_dump, which ships with the psql executable, it’s a pretty simple progress

pg_dump --dbname={{DBNAME}} --host={{HOST}} --port={{PORT}} --username={{USERNAME}} --password --format=c > {{NAME}}.dump
# The c in --format=c stands for custom

If you’re dumping to a directory archive format¹, you can use -j to parallelize this operation ie; pg_dump -j 4.