PBKDF2 Key Derivation Taking too long

Question

The below swift code works to decrypt encrypted values from my encrypters on Dart, Android and Javascript.

The problem is that that the key derivation takes way too long (~15-20 seconds). This uses CryptoSwift. I realize that a release build would reduce it a lot, but not enough.

Is there a better way to generate the PBKDF2 key? PBKDF2 key derivation is suitably fast on my other platforms @ 10,000+ iterations.

import CryptoSwift

func decryptGCM (cipherTextEnc:String, masterPass:String) -> String {
    do {
        let cipherEncComps = cipherTextEnc.components(separatedBy: "-")
        //      GET ENCRYPTED VALS
        let ivString = cipherEncComps[0]
        print (ivString)
        let saltString = cipherEncComps[1]
        print (saltString)
        let cipherTextString = cipherEncComps[2]
        print (cipherTextString)
        
        //      CREATE SALT (Decode Base64 to UTF8)
        let salt = [UInt8](base64: saltString)
        
        //      CREATE IV (Decode Base64 to UTF8)
        let iv = [UInt8](base64: ivString)
        
        //      CREATE decodedCipherString (Decode Base64 to UTF8)
        let cipherData = [UInt8](base64: cipherTextString)
        
        //      CREATE KEY & DECRYPT
        let password: [UInt8] = Array(masterPass.utf8)
        /* Generate a key from a `password`. Optional if you already have a key */
        
        let key = try PKCS5.PBKDF2(
            password: password,
            salt: salt,
            iterations: 10000,
            keyLength: 32, /* AES-256 */
            variant: .sha256
        ).calculate()
        
        print ("key generated")
        let gcm = GCM(iv: iv, mode: .combined)
        let aes = try AES(key: key, blockMode: gcm, padding: .noPadding)
        let cipherTextBytes = try aes.decrypt(cipherData)
        let cipherText = String(decoding: cipherTextBytes, as: UTF8.self)
        print ("cipherTextGenerated")
        return cipherText
    } catch {
        print("CAUGHT!")
        let errorString = "error in key derivation"
        return errorString
    }
}