# Digital Assets and On-Chain Finance — fintech-algorithms

> 10 algorithms in 2 families, sliced out of the
> fintech-algorithms reference. Zero-dependency TypeScript: plain arrays and objects in,
> plain values out. This file covers D25 only.

D25 · 10 topics · 2 families · 0 verified
Install: npm install fintech-algorithms
Agent skill (install it rather than re-deriving this file): npx skills add IslamBaraka90/Fintech-Algorithms-Library
  what it is: https://docs.thefintechbuilder.com/guides/agent-skill/
Source: fintech-algorithms@0.12.0 · payload schema 2.0.0
Reference payload: https://docs.thefintechbuilder.com/reference/payload.json
Version endpoint: https://docs.thefintechbuilder.com/version.json
Domain page: https://docs.thefintechbuilder.com/digital-assets-and-on-chain-finance/
Full index (324 topics across 13 domains): https://docs.thefintechbuilder.com/llms.txt

Verification tiers:
- verified — the worked example is the figure published in the algorithm's article, replayed
  and asserted by the test suite on every run. The arithmetic cannot drift without the build
  failing. Treat the numbers as reproducible.
- contract — the module loads, the entry point is callable and its declared signature matches
  the compiled code. The example is real captured output, but no independently published
  figure asserts it. Treat the shape as reliable and the numbers as unattested.
Full explanation: https://docs.thefintechbuilder.com/guides/verification/

Each entry: name — signature — archetype — verification tier — docs URL
From the docs URL, mechanically:
  import subpath — swap the https://docs.thefintechbuilder.com/ prefix for fintech-algorithms/ and drop the trailing slash
  markdown page  — append index.md; same contract as the HTML page, a fraction of the bytes

## D25-F01 — AMM Pricing
https://docs.thefintechbuilder.com/digital-assets-and-on-chain-finance/amm-pricing/

- Constant-Product AMM — `constantProductQuote(reserve0, reserve1, amount0In, feeRate)` — record-transform — contract — https://docs.thefintechbuilder.com/digital-assets-and-on-chain-finance/amm-pricing/constant-product-amm/
- Constant-Sum AMM — `constantSumQuote(reserve0, reserve1, amount0In, feeRate)` — record-transform — contract — https://docs.thefintechbuilder.com/digital-assets-and-on-chain-finance/amm-pricing/constant-sum-amm/
- StableSwap Invariant — `stableSwapQuote(balances, amountIn, amplification, feeRate, inputIndex, outputIndex)` — record-transform — contract — https://docs.thefintechbuilder.com/digital-assets-and-on-chain-finance/amm-pricing/stableswap-invariant/
- Weighted-Product AMM — `weightedProductQuote(balanceIn, balanceOut, weightIn, weightOut, amountIn, feeRate)` — record-transform — contract — https://docs.thefintechbuilder.com/digital-assets-and-on-chain-finance/amm-pricing/weighted-product-amm/
- Concentrated-Liquidity Position — `concentratedLiquidityPosition(liquidity, priceLower, priceUpper, currentPrice)` — record-transform — contract — https://docs.thefintechbuilder.com/digital-assets-and-on-chain-finance/amm-pricing/concentrated-liquidity-position/

## D25-F02 — Liquidity and Liquidation
https://docs.thefintechbuilder.com/digital-assets-and-on-chain-finance/liquidity-and-liquidation/

- Impermanent-Loss Calculation — `impermanentLoss(data, config)` — record-transform — contract — https://docs.thefintechbuilder.com/digital-assets-and-on-chain-finance/liquidity-and-liquidation/impermanent-loss-calculation/
- Liquidity-Provider Fee APR — `feeApr(data, config)` — record-transform — contract — https://docs.thefintechbuilder.com/digital-assets-and-on-chain-finance/liquidity-and-liquidation/liquidity-provider-fee-apr/
- Collateral-Health Factor — `healthFactor(data, config)` — record-transform — contract — https://docs.thefintechbuilder.com/digital-assets-and-on-chain-finance/liquidity-and-liquidation/collateral-health-factor/
- Liquidation-Price Calculation — `liquidationPrice(data, config)` — record-transform — contract — https://docs.thefintechbuilder.com/digital-assets-and-on-chain-finance/liquidity-and-liquidation/liquidation-price-calculation/
- Liquidation Waterfall — `liquidationWaterfall(data, config)` — record-transform — contract — https://docs.thefintechbuilder.com/digital-assets-and-on-chain-finance/liquidity-and-liquidation/liquidation-waterfall/