gistfile1.swift

import KeychainAPI

let keychain: Keychain = Keychain(service: "com.secondgear.myapp", accessibility: Accessibility.WhenUnlocked)
let userAccount = Account(userName: "justinw@me.com", secret: "lovesecretsexgod")
keychain.add(userAccount)

let fetchedAccount:Account? = keychain.accountFor("justinw@me.com")
if (fetchedAccount != nil)
{
    fetchedAccount?.secret = "newpassword"
    keychain.update(fetchedAccount!)
}

keychain.remove(fetchedAccount!);