About Cairn

A cairn is a pile of stones left by a traveller to mark the way for whoever follows. This service is a cairn made of sentences — one sentence each, from one person, once in a lifetime.

You write fifty characters. You pay a small fee. You never come back.

Why it exists

Most places on the internet ask you to speak often, quickly, and loudly. Cairn asks you to speak only once, and carefully. The question is simple: if the person coming after you could read a single sentence of yours, what would it be?

How it is run

Cairn is operated by a single individual as a sole proprietorship. No investors, no ads, no tracking cookies. The operator's full legal contact information is published in the Commercial Disclosure page (required under Japan's Act on Specified Commercial Transactions).

Money

Writing costs $3 or $1, depending on the country you write from. The two tiers reflect differences in local purchasing power, so the burden of writing feels roughly the same wherever you are. You can optionally add a donation at checkout.

Of the base fee, after payment processing fees, infrastructure costs, and taxes, 50% is donated to third-party public-interest organizations. The remaining 50% covers operations and the operator's compensation.

Voluntary donation amounts are donated in full (100%), less only payment processing fees.

Where donations go

Selection criteria: independent audit and transparent reporting, diverse missions, non-political and non-religious, internationally recognized or meaningfully active in Japan. Eight recipients:

• Médecins Sans Frontières (MSF) — emergency medical care in conflict and underserved areas
• UNHCR — protection of displaced people
• Internet Archive — long-term preservation of the human record
• Wikimedia Foundation — continued access to free knowledge
• GiveDirectly — unconditional direct cash transfers to people living in extreme poverty
• Electronic Frontier Foundation (EFF) — defending civil liberties in the digital world
• AAR Japan (難民を助ける会) — Japan-based humanitarian NGO: refugees, disability inclusion, mine action
• Against Malaria Foundation (AMF) — bed nets in malaria-endemic countries; per-net public ledger

The set is reviewed every six months. Any change is announced in advance through the Terms and the transparency page.

Transparency and voting

Every six months, the operator publishes a transparency report covering donation amounts, recipients, and a summary of operating costs, and remits donations on the same cadence. The report is shown on the transparency page.

The split between recipients is decided by the writers themselves. When your stone is laid, you receive a proof key — a 32-character private hash known only to you. At each half-yearly report, you sign in to the ledger page with your full name and proof key and allocate 0–100 across the recipients (summing to 100). Distribution is computed proportionally from the sum of all allocations: not majority vote, so minority preferences are reflected in full.

Identity

At the moment of writing, you provide your full name (Latin letters), email, year of birth, and country by self-attestation. Your name and email are kept private and used only to verify it is you when you return to the ledger to vote.

To prevent the same person from writing more than once, registrations are matched against existing email addresses, real names, and payment-card fingerprints; a match on any axis is rejected. No other identity check is required up front. The operator may still request ID documents afterward where there is reasonable cause (suspected fraud, duplicate registration, etc.).

Contact

privacy@c4irn.net