# Use Pink Extension

## Introduction#

All the unique capabilities of Phat Contract are implemented in pink-extension. Informally speaking:

$Phat\ Contract = ink! + Pink\ Extension$

It is worth noting that the Phat Contract is not a trivial extension of ink! contract since all these extra functions only work under the off-chain computation.

## Pink Extension Functions#

FunctionalityFunction NameQuery SupportTransaction Support
Internet Accesshttp_request
Cryptogetrandom
ecdsa_sign_prehashed
ecdsa_verify_prehashed
sign (ecdsa/ed25519)
sign (sr25519)
verify
derive_sr25519_key
get_public_key
Volatile Cachecache_set
cache_set_expire
cache_get
cache_remove
Misclog
is_running_in_command

Refer to our Phat Hello World contract to see how you can import these functions to your contract.