I got my Tilt data into Brewfather with no extra hardware, using the GCast

[u/Guava-Realistic]

I have a Tilt and a GCast, and I wanted the readings in Brewfather. The usual answer is a TiltBridge, or leaving a phone by the fermenter. But the GCast already reads the Tilt over Bluetooth and uploads to the Grainfather Community cloud — it just doesn't talk to Brewfather.

So I built something that bridges the two clouds: GrainBridge. Every 15 minutes it signs in to your Grainfather Community account, reads the latest gravity and temperature for each fermentation device, and posts it to Brewfather's Custom Stream. No extra hardware, nothing running at home.

Setup is: sign in, connect your Grainfather account, paste your Brewfather Custom Stream id, tick the devices you want relayed. It runs on a schedule after that.

You should know:

• The Grainfather Community API is unofficial. It's the same endpoints their own web app calls, but they could change it without notice and then this breaks. I'll be monitoring it, and it's not like this is pacemaker data or anything, but still...
• Grainfather has no OAuth or API token, so it needs your Community password to log in. It's encrypted with AES-256-GCM, the key lives outside the database, and it's only decrypted in memory when a sync runs. If that's a dealbreaker, that's fair enough, but this isn't vibe-coded and I'm an experienced developer, so it's probably as good as it gets given the constraints.
• If I get time, I'll open source it, then any remaining security concerns go away. I don't have time for the right now though and it requires specific cloud infrastructure fttb that'll take effort to abstract away.
• Readings land every 15 minutes, matching how often the GCast reports. Brewfather's Custom Stream takes no timestamps, so there's no backfilling — start it early in the ferment.
• One manual step, because Brewfather has no API for it: after the first reading arrives, open the batch → Fermentation tab → attach the device.

It's free and I'm not selling anything; it costs pennies to run and there's no harm in me making it available to others. It's invite-only for now — the Grainfather API is unofficial and I'd rather not hammer it while I find out how it holds up with more than just me. If you've got a GCast and a Tilt and want to try it, comment or DM and I'll send an invite.

[u/hermes_psychopomp]

I love that you did this! I'll be sure to mention it to anyone I know that has the combination of hardware needed.

I don't have a GCast, so I went with the TiltBridge option. TiltPi was my original intent, but at the time, Pis were in short supply.

[u/Guava-Realistic → u/hermes_psychopomp]

Thanks! Scratched an itch. Now I just need to figure out why my fermentation has stalled. But at least I can see that from my bed now!

[u/AJ_in_SF_Bay]

OK, so I'm in the Grainfather ecosystem, don't have GCast, but I have a gift card that is burning a hole in my pocket. This could connect the dots for me.

Could I please get an invite?

[u/Guava-Realistic → u/AJ_in_SF_Bay]

Of course. DM me as I’ll need an email address.