We’ve had a few off-line discussions on how to maybe go about this with @mattklein123 but we’re now close enough it’s worth filing a tracking issue for it :-)

Here’s our plan A - any Envoy devs interested in QUIC support are encouraged to offer suggestions/improvements

Milestone 1 is to hack together “something which builds” using the existing Google QUIC code*, because as it turns out it takes years to debug all the weird corner cases in congestion control and crypto and it’s likely easier to copy existing code than write it all from scratch. That code base is “supposed to” build fairly cleanly as long as one implements all the things in quic/platform/impl but almost certainly doesn’t. This will be done in in @juvexp’s Envoy branch to allow rapid iteration - any interested parties are welcome to follow along and/or contribute there. Once the QUIC code builds and QUIC unit tests pass, it’s on to Milestone 2.

Milestone 2 is to get QUIC “working” with Envoy, where we have working integration tests. This may not include clean Envoy API use. For example, the first pass might treat QUIC as one logical Connection rather than one-Connection-per-stream Milestone 2 will likely involve landing some code in Envoy (things like UDP listeners if @cmluciano hasn’t beat us to it)

Milestone 3 is having QUIC fully landed in Envoy, with proper API wrappers for all the various codec / connection / crypto functionality QUIC supports. This will involve slowly cleaning up anything still only in @juvexp’s Envoy branch, along with having a story for gracefully handling upstream/downstream updates and contributions.

*currently visibile at https://github.com/chromium/chromium/tree/master/net/quic. Plot twist, while we’re hacking around in a custom branch the Google devs are likely to use “upstream” QUIC code, since then they can make changes to code structure and push them directly to Envoy rather than pushing from google3-upstream to Chrome to Envoy which will really slow development. Long term code syncing is a big glaring TBD as we need a library non-Googlers can contribute to, but also want to cheaply and easily get the latest security fixes and IETF spec updates from the dedicated Google dev team working on QUIC.