Soft Fork

idiom

Meaning

A backward-compatible protocol upgrade that older software still accepts under certain conditions.

Origin

disputed origin

Soft signals that the change stays compatible with previous versions.

Examples

SIMPLE

SegWit was introduced through a soft fork.

CONTEXTUAL

A soft fork tightens the rules without forcing older nodes off the network.

COMPLEX

Unlike its harder cousin, a soft fork stays backward-compatible, so nodes that never upgrade still accept the new blocks as valid.

Last updated July 19, 2026