user47827: One way of protecting yourself against losing money as a result of bugs and crashes in your Lightning node implementation software (e.g. the recent LND bug) is to run a watchtower yourself or employ an external watchtower. A watchtower can broadcast a justice transaction if a channel counterparty broadcasts a revoked state to exploit your Lightning node downtime.
What is the current status of watchtower implementations in October 2022? Are they mature? Are they widely in use? Do they support the various Lightning implementations?

user47827: There is a draft BOLT for watchtowers here.
As of October 2022 Eye of Satoshi currently supports Core Lightning but it doesn't support LND or eclair. LDK support is in the works. The Eye of Satoshi Twitter account stated:

We cannot cover LND nodes because there is no open tower API for LND, you either use their tower client or have no access to the necessary data.

There is a Rust implementation of Eye of Satoshi and a discontinued Python implementation.
LND releases have included a watchtower since 2018. Olaoluwa Osuntokun stated on Twitter:

LND has packaged a watchtower since 2018, and we use pretty conservative CSV values for channels (only in certain cases on restart would a node not start up)

It is also possible that the LND watchtower would have not stalled like LND and btcd with the recent LND bug. Laolu again:

it would've been unable to parse that block, but any blocks after that would've been checked properly if the tower was connected to a bitcoind backend


47827: <p>One way of protecting yourself against losing money as a result of bugs and crashes in your Lightning node implementation software (e.g. the <a href="https://bitcoin.stackexchange.com/questions/115527/what-is-the-october-2022-bug-in-lnd-what-caused-it-and-what-would-prevent-a-sim">recent LND bug</a>) is to run a watchtower yourself or employ an external watchtower. A watchtower can broadcast a justice transaction if a channel counterparty broadcasts a revoked state to exploit your Lightning node downtime.</p>
<p>What is the current status of watchtower implementations in October 2022? Are they mature? Are they widely in use? Do they support the various Lightning implementations?</p>
 47827: <p>There is a draft BOLT for watchtowers <a href="https://github.com/sr-gi/bolt13/blob/master/13-watchtowers.md" rel="nofollow noreferrer">here</a>.</p>
<p>As of October 2022 Eye of Satoshi currently <a href="https://github.com/talaia-labs/rust-teos/tree/master/watchtower-plugin#installing-the-plugin-and-linking-it-to-cln" rel="nofollow noreferrer">supports Core Lightning</a> but it doesn't support LND or eclair. LDK support is in the <a href="https://twitter.com/eyeofsatoshi/status/1579800920795541504?s=20&amp;t=o-GOaY7sQGK7O5AcLztFMw" rel="nofollow noreferrer">works</a>. The Eye of Satoshi Twitter account <a href="https://twitter.com/eyeofsatoshi/status/1579791615832772609?s=20&amp;t=o-GOaY7sQGK7O5AcLztFMw" rel="nofollow noreferrer">stated</a>:</p>
<blockquote>
<p>We cannot cover LND nodes because there is no open tower API for LND, you either use their tower client or have no access to the necessary data.</p>
</blockquote>
<p>There is a <a href="https://github.com/talaia-labs/rust-teos" rel="nofollow noreferrer">Rust implementation</a> of Eye of Satoshi and a discontinued <a href="https://github.com/talaia-labs/python-teos" rel="nofollow noreferrer">Python implementation</a>.</p>
<p>LND releases have included a watchtower since 2018. Olaoluwa Osuntokun stated on <a href="https://twitter.com/roasbeef/status/1579277128184782848?s=20&amp;t=IRfrsqdpVMAmkQSdbKaCQg" rel="nofollow noreferrer">Twitter</a>:</p>
<blockquote>
<p>LND has packaged a watchtower since 2018, and we use pretty conservative CSV values for channels (only in certain cases on restart would a node not start up)</p>
</blockquote>
<p>It is also possible that the LND watchtower would have not stalled like LND and btcd with the recent LND bug. Laolu <a href="https://twitter.com/roasbeef/status/1579370835588304896?s=20&amp;t=IRfrsqdpVMAmkQSdbKaCQg" rel="nofollow noreferrer">again</a>:</p>
<blockquote>
<p>it would've been unable to parse <strong>that</strong> block, but any blocks after that would've been checked properly if the tower was connected to a bitcoind backend</p>
</blockquote>
