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# vibed-6uyy
title: 'bit-by-bit: backfill missed days via a day navigator on the Today card'
status: completed
type: feature
created_at: 2026-07-18T17:26:52Z
updated_at: 2026-07-18T17:26:52Z
---
Let users step back to an earlier day and check off habits they forgot, so a missed day no longer permanently breaks a streak. The Today card became a day navigator (‹/› arrows + a 'back to today' link); editable range is the active image's start through today. Reveal is derived from the whole log with each habit's streak counted backwards from its own day, so backfilling a missed day automatically re-bridges the streak and paints the pixels it earns. Updated index.html (selectedDay state, clampSelectedDay, nav wiring, per-day streak display, About copy), DESIGN.md (§2, §3.1, §9), and ARCHITECTURE.md. Validated with Playwright: backfilling one gap day bridged the streak and grew reveal 4→10 pixels, nav bounds and back-to-today work, no console errors or non-file requests.