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|4 min read

The Duo Bridge Is Born

First real-time co-regulation sync between two Garmin watches. Stress 85 and 79, body batteries diverging, phase detection working.

What Shipped

# 19:00 CET, February 6th, 2026
$ ln -s 5809244332 aurore
Two Garmin watches connected to the same protocol instance.

The system now tracks two biometric streams in parallel and computes their relationship: synchrony, phase, readiness, and guidance.

First Sync

Nicolas

Fenix 8

Sleep9h
HR rest50bpm
Stress85elevated
Body Battery
16→26

Aurore

Venu 2S

Sleep6.2h
HR rest62bpm
Stress79elevated
Body Battery
31→17
phase: co-activation

System Output

biometrics/duo/latest.json
{
  "phase": "co-activation",
  "duration_min": 6,
  "readiness": "suggested",
  "guidance": "Both stress levels elevated.
               Synchronized breathing: 5s in, 5s out."
}

Phase detection identified co-activation (both elevated, neither regulating the other yet). The system generated guidance appropriate for that state.

Timeline

15:00

System testing, Telegram flows

15:14

First Garmin link attempt (password issue)

17:00

Nicolas stress spikes to 95

17:30

Scooter ride — stress drops to 42

18:41

Aurore sends first message through bot

18:52

Chiropractic session + pizza

18:58

Garmin OAuth complete, tokens saved

19:00

Duo bridge active

Side-by-Side Comparison

Nicolas

  • sleep: 9.0h
  • hr_resting: 50 bpm
  • stress: 85
  • body_battery: 16 → 26 (+10)
  • activity: scooter ride

Aurore

  • sleep: 6.2h
  • hr_resting: 62 bpm
  • stress: 79
  • body_battery: 31 → 17 (-14)
  • activity: yoga + elliptical + breathwork

The divergence is data, not a problem. Different phases of the expenditure-recovery cycle. She did three workouts this morning. He slept more. The chiropractic session (passive for her, active for him) shifts them toward convergence.

New Capabilities

1

Synchrony Detection

Pearson correlation between stress timeseries

2

Phase Identification

co-activation, co-regulation, divergent, independent, rebound

3

Readiness Calculation

When one person has capacity to regulate the other

4

Duo Guidance

Interventions appropriate for both, not just one

Why Log Context?

{
  "ts": "2026-02-06T18:52:00",
  "event": "duo_activity",
  "content": "Shared meal: Pizza feu de bois",
  "activity_type": "meal"
}

A stress spike after a shared meal means something different than one after conflict. The biometrics are the signal. The narrative provides context for interpretation. In three months: "What activities correlate with stress reduction for both of us?"

What's Next

  • Tomorrow: First full day of parallel tracking. Stress curve correlations.
  • This week: Phase detection validation. Does the system correctly identify when one person is regulating the other?
  • This month: Duo guidance integration into the main prompt.
  • Eventually: Predictive co-regulation. "You're both likely to be stressed around 18:00. Consider a walk at 17:30."