In memoriam

Diary

“Jumpstart your diary.”

Active
June 2023 – February 2024
Closed
Lived at
diary.derekxwang.com
The Diary landing page
The landing page at diary.derekxwang.com, captured on its last day.

What it was

Diary started as a ChatGPT plugin. You opened a chat, told Diary to start the day, and then typed whatever crossed your mind. ChatGPT answered every note with a quiet #### and kept collecting. When you ended the day, it rewrote everything into a proper entry, with the key takeaways and, if anything had a time attached, a calendar file to go with it.

The landing page promised to turn random daily notes into an insightful diary, and the diary into actionable steps. That was the whole idea.

When OpenAI opened the GPT Store on January 10, 2024, I wrapped the same API as a GPT action and shipped Diary GPT that day.

What I built

  • A ChatGPT plugin on AWS Lambda and API Gateway, deployed with SST v2: an ai-plugin.json and OpenAPI spec under /.well-known, behind a service bearer token.
  • start and stop endpoints that handed ChatGPT its instructions for the day, in English and in Chinese.
  • A calendar endpoint that saved the generated ICS file to S3 and returned a short link from my own shortener at l.derekxwang.com.
  • A Remix and Tailwind landing page at diary.derekxwang.com, plus the legal page the plugin manifest pointed to.
  • Diary GPT in the GPT Store, calling the plugin’s API.

How it ended

OpenAI shut down ChatGPT plugins in 2024, and the plugin had nowhere left to run. Diary GPT leaned on the same API. I closed Diary on 2026-10-07, when I retired the old SST v2 app that hosted it.

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