Shiny small one with feathered antennae

Shiny small one with feathered antennae

Observation - Shiny small one with feathered antennae - UK and Ireland. Description: Completely stumped by this one. Small (3mm maybe) shiny insect with very distinctive feathered antennae at the house lights over several nights at the start of September. Not even sure if it's a fly or a wasp. Ideas?

Completely stumped by this one. Small (3mm maybe) shiny insect with very distinctive feathered antennae at the house lights over several nights at the start of September. Not even sure if it's a fly or a wasp. Ideas?