You could use either the version I committed — see below:

"If you are an hapi developer, you may know the joi library. It is a powerful validation library that allows you to define programmatic schemas for your data and validate them with ease."

Or 

"If you are an hapi developer, you may know the joi library. It is a powerful validation library that allows you to programmatically define schemas for your data and validate them with ease."

Really great work. I just made a few minor tweaks as part of this commit. 

I'll explain my reasoning for the changes I made to this section.

- buildValidator: The function to pass to the schemaController option of Fastify.
- bucket: The joi bucket that contains the schemas when you call the app.addSchema(joiSchema) method. You can omit this option if you don't use. app.addSchema
- joi: A customized joi instance that contains the installed extensions, if there are any. It is a good practice to use this instance to build your schemas.

I added capitalisation (title case) and full stops to all of the bullets because the second two bullet points have two sentences. 

This meant you'd used title case in the second part of those bullet points and punctuation in the first point.

So, I made the changes I did to make sure things were consistent — title case at the start of each bullet point and punctuation at the end of each bullet point.

Let me know if you have any questions about what I did 🙂.