Snowflake stock closed up 36% on Thursday, its best day ever, after the company boosted guidance and announced an AI compute deal with Amazon (Samantha Subin/CNBC)

Samantha Subin / CNBC: Snowflake stock closed up 36% on Thursday, its best day ever, after the company boosted guidance and announced an AI compute deal with Amazon — Software stocks popped on Thursday after Snowflake said it plans to spend $6 billion on compute from Amazon and topped earnings estimates on artificial intelligence momentum.