83f9cde22c583d79

// import tls "github.com/refraction-networking/utls"
tcpConn, err := net.Dial("tcp", "tlsfingerprint.io:443")
if err != nil {
	fmt.Printf("net.Dial() failed: %+v\n", err)
	return
}

config := tls.Config{ServerName: "tlsfingerprint.io"}
// This fingerprint includes feature(s), not fully supported by TLS.
// uTLS client with this fingerprint will only be able to to talk to servers,
// that also do not support those features. 
tlsConn := tls.UClient(tcpConn, &tlsConfig, tls.HelloCustom)
clientHelloSpec := tls.ClientHelloSpec {
	CipherSuites: []uint16{
		tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,
		tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305,
		0xccaa,
		tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
		tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
		0x009f,
		0xc0ad,
		0xc09f,
		tls.DISABLED_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384,
		tls.DISABLED_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384,
		0x006b,
		tls.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
		tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
		0x0039,
		0xc0af,
		0xc0a3,
		0xc087,
		0xc08b,
		0xc07d,
		0xc073,
		0xc077,
		0x00c4,
		0x0088,
		tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
		tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
		0x009e,
		0xc0ac,
		0xc09e,
		tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,
		tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
		0x0067,
		tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
		tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
		0x0033,
		0xc0ae,
		0xc0a2,
		0xc086,
		0xc08a,
		0xc07c,
		0xc072,
		0xc076,
		0x00be,
		0x0045,
		tls.TLS_RSA_WITH_AES_256_GCM_SHA384,
		0xc09d,
		tls.DISABLED_TLS_RSA_WITH_AES_256_CBC_SHA256,
		tls.TLS_RSA_WITH_AES_256_CBC_SHA,
		0xc032,
		0xc02a,
		0xc00f,
		0xc02e,
		0xc026,
		0xc005,
		0xc0a1,
		0xc07b,
		0x00c0,
		0x0084,
		0xc08d,
		0xc079,
		0xc089,
		0xc075,
		tls.TLS_RSA_WITH_AES_128_GCM_SHA256,
		0xc09c,
		tls.TLS_RSA_WITH_AES_128_CBC_SHA256,
		tls.TLS_RSA_WITH_AES_128_CBC_SHA,
		0xc031,
		0xc029,
		0xc00e,
		0xc02d,
		0xc025,
		0xc004,
		0xc0a0,
		0xc07a,
		0x00ba,
		0x0041,
		0xc08c,
		0xc078,
		0xc088,
		0xc074,
		0x00ff,
	},
	CompressionMethods: []byte{
		0x00, // compressionNone
	},
	Extensions: []tls.TLSExtension{
		&tls.SNIExtension{},
		&tls.SignatureAlgorithmsExtension{SupportedSignatureAlgorithms: []tls.SignatureScheme{
			tls.ECDSAWithP521AndSHA512,
			tls.PKCS1WithSHA512,
			tls.ECDSAWithP384AndSHA384,
			tls.PKCS1WithSHA384,
			tls.ECDSAWithP256AndSHA256,
			tls.PKCS1WithSHA256,
			0x0303,
			0x0301,
			tls.ECDSAWithSHA1,
			tls.PKCS1WithSHA1,
		},},
		&tls.SupportedCurvesExtension{[]tls.CurveID{
			tls.CurveP521,
			0x001c,
			tls.CurveP384,
			0x001b,
			tls.CurveP256,
			0x0016,
			0x001a,
			0x0015,
			0x0014,
			0x0013,
			0x0012,
			tls.X25519,
			0x001e,
		}},
		&tls.SupportedPointsExtension{SupportedPoints: []byte{
			0x00, // pointFormatUncompressed
		}},
		&tls.GenericExtension {Id: 0x0016}, // WARNING: UNKNOWN EXTENSION, USE AT YOUR OWN RISK
		&tls.UtlsExtendedMasterSecretExtension{},
		&tls.SessionTicketExtension{},
	},
}
tlsConn.ApplyPreset(&clientHelloSpec)
        
n, err = tlsConn.Write([]byte("Hello, World!"))
// or tlsConn.Handshake() for better control