How important is the developer audience to your business as a whole? If you're developer-focused, it's much more likely you need a developer relations team versus if developers are enabling other teams with the tools. In that case, it's less likely that you would need multiple people working directly with your developer community. Also:

• What roles do you need in dev marketing or whatever you call this thing that doesn't exist?
• What's the least I need to get started attracting developers?
• Can I just start publishing content and see what happens?