LateLetter

LateLetter is a small tool for writing private letters that someone can open later in a browser.

It is built for messages that should feel cared for after the author is not there to send them: birthday notes, grief letters, instructions, memories, apologies, encouragement, or anything else that should reach one person at the right time.

The recipient experience is intentionally simple: open a link or .lateletter file, enter the passphrase, walk through a quiet ASCII garden, and read the letters that are available for that date.

What it looks like

The public viewer is a quiet ASCII garden. Letters open from that garden when the recipient has the passphrase and the delivery date has arrived.

The terminal authoring flow is separate. It helps the author draft and package the letter before anything is sent.

How it works

LateLetter has two parts:

• The author tool turns letter drafts, dates, hints, and garden details into a sealed .lateletter bundle.
• The browser viewer lets the recipient open that bundle. The passphrase opens the private letter text; the garden, author name, hint, and delivery dates are visible around it.

The point is not just storage. The garden gives the recipient a place to arrive, wait, and return to, instead of handing them a bare encrypted file.

Quick start

Open viewer-bnw.html in a browser. Click [get demo letter] to load the demo bundle, or drop your own .lateletter file.

Demo passphrase: garden-biscuit-2026

The passcode-locked demo opens only with that passphrase. A wrong passphrase is rejected. Sealed bundles use PBKDF2-SHA256 and AES-256-GCM for the private letter body.

Send a real letter

cp letters/letter_source.example.json letters/my_letter.json
# edit letters/my_letter.json — your words, dates, hint, and Garden program
python3 make_letter.py letters/my_letter.json letters/for_them.lateletter
python3 make_letter.py --verify letters/for_them.lateletter   # round-trip check

Send letters/for_them.lateletter to your friend with a link to the viewer (https://rikiworld.com/lateletter/). Tell them the passcode in person. The builder asks for a fresh passphrase twice; it is never stored in the source JSON or output bundle. Keep the editable source and first sealed output under ignored letters/ filenames. The tracked example contains synthetic text only.

Or send just a link

Build and verify in ignored private storage first. After final copy approval, copy only the sealed output into public_letters/ and commit that bundle. A standard GitHub Pages site is public even when its source repository is private, so anyone with the URL can download the bundle; only someone with the passcode can open its private content:

python3 make_letter.py letters/my_letter.json letters/to-personx.lateletter
python3 make_letter.py --verify letters/to-personx.lateletter
cp letters/to-personx.lateletter public_letters/to-personx.lateletter
git add public_letters/to-personx.lateletter && git commit -m "letter" && git push

After the Pages deploy, share https://rikiworld.com/lateletter/to-personx/ (passcode gate included — no file handling for the recipient at all). Heads-up: your author name, the passphrase hint, and delivery dates are plaintext in the bundle, so anyone with the URL (or browsing the repo) can see those — the letter body and gift sentiments stay sealed. Demo link once deployed: https://rikiworld.com/lateletter/to-a-friend/ (passcode garden-biscuit-2026).

Production safety note

https://rikiworld.com/lateletter/ currently serves the legacy pretext-monolith viewer. That deployed version is kept as a rollback-safe release: lateletter-legacy-pages-2026-07-28.

Project structure

viewer-bnw.html          Single-file browser viewer (garden + letter reader)
test_fixture.lateletter  Demo bundle (Buddy's letter)
src/lateletter/          Python author tools (CLI, intake, bundling)
docs/                    README GIFs, release notes, visual-review receipts

Garden

The viewer renders an ASCII garden that changes with the seasons. Plants grow procedurally from a seed. Rain falls in spring and autumn, snow in winter, butterflies in summer. Clicking plants scatters particles. An animal companion appears after the first visit.

Dev tools

Load the demo fixture (no HMAC = dev mode) to unlock dev keybindings:

• , / . cycle seasons + night
• Shift+B cycle color modes
• Shift+G grid overlay with FPS
• Shift+A cycle animal types/tiers
• f feed the animal

License

Private project.