A: Depends on how you plan to use Niceboard and Hirevire together.
Hirevire currently cannot have job post creation using third party integrations. But you can be notified about new applications from Hirevire - into Niceboard.

Never having used Niceboard myself - here's some recommendations.

1. Niceboard.co seems to integrate already with Zapier - which can be used to connect to Hirevire.
https://zapier.com/apps/niceboard/integrations/hirevire
2. You can use Hirevire Webhooks to connect to Niceboard to understand when new applications are received.
https://hirevire.com/features/webhook-integration-with-answers
3. You can use the Hirevire job post - as the "apply to company link". Similar to how one would post Hirevire links on Linkedin
https://hirevire.com/linkedin-integration

Hope this helps.