Four products that can hurt people.
Designed to tell the truth.
Kotodama is a custodial exchange — spot, futures, earn, custody — the kind of product that can quietly ruin someone with a mistimed 125× position or a return that isn't what it says. So this isn't a feature tour. It's a study of the four hardest, most honest design problems the product poses, where the job of the interface is to make the danger legible, not invisible.
言葉には靈が宿る——リスクは、はっきり言う。 Words carry spirit; say the risk plainly.
What this is. A design study of an all-in-one exchange, rebuilt as original IP under a fictional brand. It is not a live product and has not been security-audited. The engineering figures it references (throughput, latency, matching) are researched and illustrative — not systems I built or benchmarked.
Where my domain ends. I design the interface and the information architecture. I don't run a matching engine, a custody desk, or a compliance function. And a deliberate stance runs through the whole study: high-leverage retail crypto derivatives are restricted or banned for retail in most regulated markets — ASIC caps retail crypto-CFD leverage; the UK FCA bans crypto derivatives to retail — so I treat the leverage not as a feature to sell, but as a risk to make understood. The honesty is the hero.
Four products, four risk profiles, one account.
An exchange isn't one product; it's four with wildly different risk. Spot can lose you your position. Futures at 125× can lose you everything in a wick. Earn can quietly under-deliver behind a headline APY. Custody can lose the lot to a bad withdrawal.
The temptation is to make each one feel exciting and frictionless. The responsible design does the opposite where it matters: it keeps the liquidation price on screen at all times, states the return two ways so it can't flatter, gates the dangerous products behind suitability, and never lets a transfer quietly wreck a position. Make the honest thing the easy thing — across all four, from one coherent account.
One balance, three ledgers, no silent damage.
Every user holds three books — spot, futures, earn — and moves value between them instantly, off-chain, at no fee. The hard part isn't the transfer; it's the guardrail: money leaving the futures account must never drop an open position below its maintenance margin. The interface has to refuse the unsafe transfer and explain why, in the moment.
The liquidation price is never off screen.
Most of what hurts people in futures is hidden: where you get liquidated, why the "price" that triggers it isn't the last trade, and the fact that leverage quietly caps out as your position grows. Kotodama surfaces all three — a permanent liquidation readout, a three-exchange mark price that resists single-venue wicks, and a tiered risk limit that lowers max leverage as size climbs. Move the leverage and watch the liquidation close in.
| Position notional (USDT) | Max leverage | Maint. margin |
|---|---|---|
| 0 – 50,000 | 125× | 0.4% |
| 50,000 – 250,000 | 100× | 0.5% |
| 250,000 – 1,000,000 | 50× | 1.0% |
| 1,000,000 – 5,000,000 | 20× | 2.5% |
| > 5,000,000 | 10× | 5.0% |
A yield that can't flatter itself.
"12% APY!" is where earn products lie. Kotodama shows APR and APY together so compounding can't inflate the headline, quotes floating rates as a 7-day annualized figure (not a guarantee), and states the early-redemption penalty before you commit, not after. Change the amount and term; see both numbers and what a fixed term actually costs to break.
You unlock danger by proving you're ready for it.
Access is progressive: a new user can look but not trade; verification opens spot and limited leverage; full verification (and a suitability step) is what unlocks high leverage and large withdrawals. It's KYC/AML doing real work — and it's also a design pattern, gating the most dangerous surfaces behind the most friction. Tap a tier.
Nine modules the design has to stay coherent across.
The four problems above sit on top of a whole exchange. I mapped it to design with the system, not around it — but the architecture and its figures are researched context, not systems I built or benchmarked.
What this evidences — and what it does not.
See it move, or read the neighbours.
A designer who holds the whole exchange — and restrains it.
That's the signal Kotodama sends: system breadth, mechanism fluency, and the judgment to make the dangerous thing honest instead of exciting.