Added2
The FAQ answers “Can I trust a service that one person builds?”, and the home's section about the developer carries the same facts.
The answer lists what can be checked from outside: the key never leaves your device, the encryption code is public, and the public recovery tool gets files out without the NMTS server. It also gives the date NMTS went public and points to the dated Update log.
The home's path for people who build something says that a business can register and open NMTS accounts for the users of its own product.
Registration is at Settings › Developer › Platform and section 3.7 of the Terms covers it. NMTS takes no fee for it.
Changed1
The site and the app are set in Inter for Latin letters and digits, and in Noto Sans KR for Korean.
Both faces are served by nmts.me, and no font is requested from another server. The Korean face is split into slices and a page downloads only the slices whose characters it shows: a first visit to the Korean home fetches about 0.6 MB of fonts where it fetched 2.75 MB. Korean letters are wider than before, so some lines break in different places. The pictures show the previous face.
Fixed1
A Korean particle was wrong in the note about the Walrus copy's size limit, in the recovery settings.