DK
EWD·001 — Determinism

Math you can prove,
not just trust.

Deterministic decimal arithmetic for DeFi. The same calculation returns the same result on x86, ARM, and WASM—down to the last digit. 28 significant digits, 7 rounding modes, zero floating-point drift.

Theorem (Determinism).
∀ platforms P, P′ · input x :  f(x)P ≡ f(x)P′
0.1 + 0.2=0.3x86ARMWASM
bit-identical · ∎ verified · 17 formal proofs (Kani)
Read the proof

Built for protocols like

Aave
Compound
Uniswap
Arbitrum
Optimism
EWD·002 — Products

Built for precision. Designed for DeFi.

Start with the open-source library. Scale with the commercial dashboard.

Open-Source Libraries

MIT Licensed

precision-core, financial-calc, and risk-metrics. Battle-tested arithmetic with 28 significant digits and 7 rounding modes.

  • 128-bit decimal precision
  • Cross-platform determinism
  • no_std compatible
View on crates.io

WASM Bindings

npm

@dijkstra-keystone/keystone-wasm. Same precision guarantees in the browser. 65KB optimized bundle.

  • Browser & Node.js
  • TypeScript definitions
  • Async initialization
View on npm

Risk Dashboard

Commercial

Multi-protocol DeFi monitoring. Track positions across Aave, Compound, and Uniswap with real-time alerts.

  • Health factor tracking
  • Liquidation warnings
  • Webhook alerts
View pricing
EWD·003 — Production

Shipped, tested, documented

Real infrastructure for financial computation. Published on crates.io, determinism-verified across platforms, ready for production.

128
bit precision
5
Stylus contracts
17
proof harnesses
0
unsafe code

Core Arithmetic

  • 28 significant digits
  • 7 rounding modes
  • Banker's rounding (IEEE 754)
  • Overflow-safe operations

Financial Functions

  • Black-Scholes pricing
  • Options Greeks (δ, γ, θ, ν, ρ)
  • Implied volatility solver
  • Compound interest / NPV

DeFi Integration

  • RedStone oracle integration
  • Health factor calculations
  • Liquidation math
  • Options pricing (Black-Scholes)

Verification & Testing

  • SP1 zkVM proving
  • Kani formal verification
  • Motsu contract testing
  • no_std + WASM targets
EWD·004 — On-chain · Arbitrum One

Deployed to mainnet

Production Stylus contracts using Keystone precision arithmetic. Deployed to Arbitrum One, verified and callable. Part of a 5-contract example suite covering lending, AMM, vaults, options pricing, and oracle integration.

Fig. — measured gas · Arbitrum One

Stylus vs Solidity

OperationStylusSoliditySavings
APY calculation (365 loops)75,316148,88149%
Compound yield (30 loops)59,51333,205
Share price58,74222,606

Stylus excels at computation-heavy operations (100+ iterations).

EWD·005 — Proof

Same input. Same output.
Every platform.

Standard floating-point arithmetic:

0.1 + 0.2 = 0.30000000000000004

Keystone produces byte-identical results whether you run on x86 servers, ARM mobile, or WASM in browsers. No reconciliation failures. No cross-platform bugs. No audit surprises.

28
Significant digits
7
Rounding modes
~8ns
Per operation
100+
Property tests
terminal
x86_64 Linux
$ keystone eval "0.1 + 0.2"
0.3
ARM64 macOS
$ keystone eval "0.1 + 0.2"
0.3
WASM Browser
$ keystone eval "0.1 + 0.2"
0.3

All platforms produce identical output.

EWD·006 — Access

Transparent pricing

Start free with the open-source libraries. Upgrade when you need monitoring.

Libraries

Free

Open-source, forever. MIT licensed.

  • precision-core, financial-calc, risk-metrics
  • WASM bindings
  • Community support
Get Started
Recommended

Dashboard

$99/mo

For developers and small teams.

  • Multi-protocol monitoring
  • Real-time health tracking
  • Email & webhook alerts
Start Free Trial

Protocol

Custom

For DeFi protocols. Volume-based pricing.

  • Dedicated infrastructure
  • Custom integrations
  • SLA & audit support
Contact Us
EWD·007 — Build ∎

Start with the library.
Scale with the dashboard.

Deterministic computation for DeFi protocols.