How much would your mother get, every month, for the rest of her life?
Tell us a little about her. Robinhood Chain works it out in about a second: 512 possible futures, simulated by a contract on the chain, not on our server.
When a member dies, the others’ lights get brighter.
That is the whole idea. A pension fund pools lives so nobody has to guess how long they will live. Tonti does it without a fund: when a member dies, the at-risk part of their savings is shared among the members still alive, fairly, by age and amount.
Year 1965
- {count} still alive
- 2,000 still alive
- Each gets {amount} a year (today’s dollars)
The pool paid every one of them, every year, for as long as they lived.
A replay: 2,000 Filipino women retire in 1965 with $10,000 each, through the real stock-market and T-bill history since. Their lives are simulated from UN mortality tables; the returns are what happened.
A life, drawn as one day.
Morning. Pay in while you work.
From your wage in Singapore, for yourself or for a parent back home. Any amount, any month.
Noon. It is invested for her.
In the S&P 500 and US Treasury bills, as tokens on Robinhood Chain, moving to safer holdings as she gets older.
Dusk. Income, for life.
From the age you choose, between 50 and 80: paid every month to her own wallet, for as long as she lives.
Night. Her family is looked after.
Keep part of the savings as a bequest. It goes to her family, never to the pool.
Nobody can take the pot. Not even us.
By 1905, two-thirds of American life insurance was tontine insurance. New York banned it in 1906, not because tontines failed, but because the companies running them stole from them. A contract can’t.
The rules are code on Robinhood Chain. The money sits in a contract that only pays members.
See it on the chain (0xb127…12Bc)Every three months she proves she is alive with her fingerprint or Face ID: one tap, no wallet. Her family sends it on to the chain for her.
See it on the chain (0x97e1…C03D)Her identity is checked when she joins, tied to her birth year and country, and renewed once a year: nobody can claim to be older than they are, or keep collecting for someone who has died.
See it on the chain (0xd715…a1C7)A false death report has 120 days to be answered, and can be undone for five years.
See it on the chain (0x97e1…C03D)Any change to the rules waits 48 hours in public. The mortality tables are sealed forever.
See it on the chain (0x5986…C504)A detector watches every group of members for deaths that go unreported.
See it on the chain (0xfde4…6308)
Under the hood, measured.
- 512 possible lifetimes, simulated inside one read of the chain: 9,458,297 gas, 30% of what a single call may use.
- Mortality for 1,846 cohorts (13 countries, both sexes, born 1935–2005), fitted to UN tables and sealed on the chain.
- Fair shares even in a small pool: with 100 members the bias is 0.26%, down from 5% with the textbook rule.
- 59 of 59 deliberately planted bugs, in the pool and the life registry, are caught by the tests.
- The engine is Rust, compiled for Arbitrum Stylus; the same code runs the tests, the simulator and the chain.
What this is, and what it isn’t yet.
- A research preview. Each member can pay in up to 25 USDG in total while we prove it works with real people.
- Tonti is not an insurer and not licensed by MAS. It promises no fixed amount: income depends on markets and on how long members live.
- For now the operator checks identities by video call. Passport-chip proofs will replace that.
- Income is paid in USDG, a regulated US-dollar stablecoin issued by Paxos. Turning it into pesos is up to her.