Shares Slack's exact shape: channels and real-time chat are genuinely buildable. What you'd be giving up is everything living inside the Microsoft 365 ecosystem it's bundled with.
VIBE SCORE 78/100
The parts this build actually needs, each rated on its own — the average is the Vibe Score above.
| Landing page | 99 |
| CRUD database | 95 |
| User login | 92 |
| Realtime collaboration | 67 |
| Live video / WebRTC | 35 |
Two real costs, not just "free": the AI agent's own usage, and hosting once it's running. Both are estimated from this app's own effort rating and component list — see the assumptions on the method page.
| AI agent — with a subscription (Claude Pro/Max, Cursor, etc.) | $0 marginal |
| AI agent — pay-per-use API, no subscription | $43–$86 one-time |
| Hosting, once it's running | $20–$40/mo |
| Domain name, if you want your own | ~$12/yr |
Microsoft Teams costs $6/mo, but hosting alone could run $20–$40/mo — that can eat the whole subscription saving before the agent cost even comes into it.
Don't feel like building it? These are already made, open-source, and free.
Borderline. Shares Slack's exact shape: channels and real-time chat are genuinely buildable. What you'd be giving up is everything living inside the Microsoft 365 ecosystem it's bundled with.
Microsoft Teams costs $6/mo (about $72/yr) as of 2026-08. That's what a working rebuild would save you.
Deep, seamless integration with Word, Excel, and SharePoint (co-editing a document inside a chat) is a huge, ongoing ecosystem investment, not a feature Enterprise identity and compliance tooling tied to Microsoft 365 admin doesn't come with a custom build Large-scale webinars and org-wide broadcasts are a different tier of real-time infrastructure than small-team chat
Yes — Mattermost are open-source options worth trying before you build your own. Details are in the standard parts section on this page.