bdaaf267c21d1e55

// 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.Client(tcpConn, &tlsConfig, utls.HelloCustom)
clientHelloSpec := tls.ClientHelloSpec {
	CipherSuites: []uint16{
		0x16ba,
		0x16b9,
		0x16b8,
		0x16b7,
		0xc071,
		tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
		0x00ab,
		0x009f,
		0xccad,
		0xccac,
		0xccaa,
		tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305,
		tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,
		0xc091,
		0xc08b,
		0xc087,
		0xc07d,
		0xc06d,
		0xc05d,
		0xc053,
		0xcc15,
		tls.OLD_TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256,
		tls.OLD_TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256,
		tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
		0x00aa,
		0x009e,
		0xc090,
		0xc08a,
		0xc086,
		0xc07c,
		0xc070,
		0xc06c,
		0xc061,
		0xc060,
		0xc05c,
		0xc052,
		0xc0ad,
		0xc0a7,
		0xc09f,
		0xc0ac,
		0xc0a6,
		0xc09e,
		0xc0af,
		0xc0ab,
		0xc0a3,
		0xc0ae,
		0xc0aa,
		0xc0a2,
		0xc038,
		tls.DISABLED_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384,
		0x00b3,
		0x006b,
		0xc09b,
		0xc097,
		0xc077,
		0xc073,
		0xc067,
		0xc04d,
		0xc049,
		0xc045,
		0x00c4,
		0x0088,
		0xc037,
		tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
		0x00ff,
	},
	CompressionMethods: []byte{
		0x00, // compressionNone
		0x01
	},
	Extensions: []tls.TLSExtension{
		&tls.SupportedCurvesExtension{[]tls.CurveID{
			0x001e,
			tls.X25519,
			0x0104,
			tls.CurveP521,
			0x0103,
			tls.CurveP384,
			0x0102,
			tls.CurveP256,
			0x0101,
			0x0100,
			0x000e,
			0x000d,
			0x001c,
			0x000c,
			0x000b,
			0x001b,
			0x000a,
			0x0009,
			0x0016,
			0x001a,
			0x0008,
			0x0007,
			0x0006,
			0x0015,
			0x0014,
			0x0004,
			0x0005,
			0x0013,
			0x0012,
			0x0002,
			0x0003,
			0x0001,
		}},
		&tls.SupportedPointsExtension{SupportedPoints: []byte{
			0x00, // pointFormatUncompressed
		}},
		&tls.SignatureAlgorithmsExtension{SupportedSignatureAlgorithms: []SignatureScheme{
			0x0808,
			0x0807,
			0x080b,
			0x080a,
			0x0809,
			tls.PSSWithSHA512,
			tls.PSSWithSHA384,
			tls.PSSWithSHA256,
			tls.ECDSAWithP521AndSHA512,
			tls.ECDSAWithP384AndSHA384,
			tls.ECDSAWithP256AndSHA256,
			0x0303,
			tls.PKCS1WithSHA512,
			tls.PKCS1WithSHA384,
			tls.PKCS1WithSHA256,
			0x0301,
			tls.ECDSAWithSHA1,
			0x0202,
			tls.PKCS1WithSHA1,
			0x0101,
		},},
		&tls.GenericExtension {id: 0x0016}, // WARNING: UNKNOWN EXTENSION, USE AT YOUR OWN RISK
		&tls.UtlsExtendedMasterSecretExtension{},
		&tls.UtlsPaddingExtension{GetPaddingLen: BoringPaddingStyle},
	},
}
tlsConn.ApplyPreset(clientHelloSpec)
        
n, err = tlsConn.Write("Hello, World!")
// or tlsConn.Handshake() for better control