Creating dns records via api is very slow

I need to create/update 1300 DNS records in a batch, it works fine with flarectl, but it is extremely slow apx 2-3 sec. pr update

What are your experience in regards to API speed from Go, or alternatively from Terraform ?

You are probably better off using the import feature

https://api.cloudflare.com/#dns-records-for-a-zone-import-dns-records