wiimpersonator is a tool that connects to NUS, and fetches information about any new system updates. Wiimpersonator can also fetch Wii U updates due to the Wii U having the same update system.

TypePC utility
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As of 3 April 2021, wiimpersonator no longer is checking for updates due to a dependency on the now-deprecated Python 2. Past reports are still available.

Note that the first 3 entries were not created on April 15; they were instead generated before Wiimpersonator went public. The first was from March 9th, the second from March 20th, and the third from March 22nd.

The first update detected by wiimpersonator was 3.2rev02. However, 2 days later, 3.2rev03 was released, including IOS37. This was how IOS37 was immediately discovered.

In response to the 3.5 update, wiimpersonator was updated to try various configurations on every run. This also allowed the initial Wii U titles to be downloaded 2 days before the console was released, although they could not be decrypted due to a different common key.