Why a Daily Reminder App Needs Three States, Not Just a Boolean Flag

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A developer building a self-opening morning checklist discovered that using a simple true/false boolean to track whether a reminder had been addressed created an unintended loop — closing the window without pressing the start button caused the reminder to reappear every 30 seconds. The root problem was that the boolean tracked whether the window had opened, not whether the user had actually responded to it. To fix this, the developer replaced the single flag with three distinct states: done, dismissed, and owed — where owed is simply the absence of the other two. This change also resolved two unrelated edge cases, including preventing multiple reminder windows from stacking up during late-night sessions. The open-source Windows app stores all data locally in a single JSON file with no account or server required.

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