bgcast

Type 1 · multiple daily injections

Your glucose, broadcast.

bgcast pulls your Freestyle Libre 3 readings the moment they land, runs the numbers without pause, and tells you the instant something needs attention. It informs — you inject.

One person · one database · no third-party requests

The timeline

One column, newest first: every reading, every alert, every dose. The list is the chart — scanning down it reads as the trace turned on its side.

6.2 →
In range
mmol/L · 1 min ago
In range
78%
Below
3%
Above
19%
Average
7.3mmol/L
2.5 3.9 10.0 16.1 mmol/L
Night
23:12 6.4
22:57 6.8
22:42 7.2
22:27 7.9
22:12 8.9 back in range
21:57 10.3
21:42 11.9
21:27 13.2
21:12 13.8
21:06 2 U Lyumjev confirmed
21:02 Suggested 2 U pending
Evening
20:57 13.5
20:46 High alert logged
20:42 12.5
20:27 11.0 went high
20:12 9.3
19:57 7.8
19:42 7.0
19:27 6.5

An illustrative window, not anyone's data.

How it works
  1. 1

    Connect once

    Add your LibreLinkUp login in the app. Credentials are encrypted at rest and used for nothing but fetching your readings.

  2. 2

    It watches

    Readings land in the database every few minutes. bgcast tracks time in range, models the insulin still working, and holds the thresholds you set.

  3. 3

    You decide

    When a correction is warranted it shows the arithmetic and waits. You confirm the dose you actually took, and it feeds back into the next calculation.

What you get

Live Libre 3 readings

Pulled from LibreLinkUp the moment they land. A dropout leaves a gap you can see rather than a line drawn across data that was never there.

Alerts that arrive

Low, predicted low, high and very high, with hysteresis and cooldowns so the ones that matter aren't buried under the ones that don't.

Correction suggestions

Insulin on board from your own curve, your ISF, your target. Every suggestion shows its working, and a stack of guards can hold it back.

Loud failure

The dangerous mode is stale data that looks current. Ingest health sits on the page permanently and old readings are visibly demoted in place.

Private by construction

One process, one database, no analytics, no CDNs and no third-party requests. Nothing about you is sent anywhere.

Time in range

The headline number, next to what it was over the window before — a figure with nothing to compare it against isn't telling you much.

Built to fail loudly

Most of the correction engine is the part that refuses to suggest anything. It holds fire when the data is stale, when you're low or heading low, when glucose is rising faster than insulin can explain, when a dose is still working, when you're already at your insulin-on-board ceiling, and overnight — and it records the reason every time, so the timeline can always answer why nothing happened.

The engine ships switched off, and stays off until you have been through your own dosing parameters and turned it on deliberately. The shipped defaults are placeholders, not recommendations.

Honest answers

Does it dose for me?

No, and it never will. It suggests; you decide and you inject. That is the whole design — the software is the controller, you are the actuator.

Which sensors work?

Freestyle Libre 3, through LibreLinkUp. That is a reverse-engineered API with no official support, and it can break without notice.

Where does my data live?

In a single database and nowhere else. There is no bgcast account, no third party in the loop, and nothing phones home.

Is it a medical device?

No. It is not certified, not clinically validated, and has not been near a regulatory process. Treat every number as a suggestion to check.

Your glucose, without the guesswork.

Read the About page first — it is short, and it is the part worth reading before trusting anything here.