Before You Begin

Before starting your Fireblocks EW implementation, we want to distinguish the two parts that comprise it:

• The Fireblocks EW client SDK (also referred to as the EW SDK).
• And the Fireblocks SDK.

Each SDK is a part of the complete solution, but each SDK has a distinct purpose.

• The EW SDK is primarily used in your client implementation.
• The Fireblocks SDK is primarily used in your backend implementation and is initialized with an API user key. There are two instantiations of the Fireblocks SDK with two unique roles: NCW Admin and NCW Signer.

If your backend isn't in Node.js, Fireblocks exposes two APIs for your use. The separation is unimportant, and the usage is similar in both.

• NCW API
• Fireblocks API

In our demo apps and throughout the documentation, we make clear distinctions between the two SDKs and when to use each SDK, but we believe it's helpful to know these specific differences ahead of time.