PSA: Making builder submission cancellations optional

[metachris]

Cancellations will start being opt-in at the Flashbots relay starting Tuesday, April 18!

If you want to use cancellations, please add this query arg to the block submission URL: ?cancellations=1

Full URL:

/relay/v1/builder/blocks?cancellations=1

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Implementation

• builder submission performance improvements, cancel opt-in #350

Context

Cancellations carry a performance penalty, because of the need to validate every single submission, whereas without cancellations we can discard submissions with a lower value, which will have a strongly positive impact on good submissions. (Note that right now we receive between 500 and 700 block submissions per slot).