# Using custom serializer

From v5.0 version there is option to provide custom serializer.

Custom serializer instance must meet a few requirements:

* Have a `encode (data)` method, that returns encoded data
* Have a `decode (data)` method, that returns decoded data
* Have a `protocol` string property, that contains a protocol name. This name is concatenated with "wamp.2." string and is then passed as websocket subprotocol http header.
* Have a `isBinary` boolean property, that indicates, is this a binary protocol or not.

Take a look at JsonSerializer.js or MsgpackSerializer.js as examples.


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