TaxChain
TypeScript · Next.js · tRPC · PostgreSQL · Redis · BullMQ · ccxt
A tax calculator for crypto, built around European rules rather than adapted from American ones. It pulls in every exchange and wallet I use, Copytrade’s Hyperliquid perps included, and works out what I owe for the year. Screenshots are from a local copy with a made-up portfolio.
Features
- Imports from everywhere: CSV exports from 14 exchanges, API sync with 10 exchanges through ccxt, on-chain history from 6 EVM chains and Solana, swaps on Uniswap, SushiSwap, Curve and PancakeSwap, Hyperliquid fills and funding, and Koinly exports
- Rules per country: calculators for Spain, Germany, France, Italy, the Netherlands, Portugal, Austria, Switzerland and the UK
- Spain in depth: spot and derivatives reported separately, loss relief carried forward, the repurchase rule, and staking income in the right tax base
- Cost basis by FIFO, LIFO, HIFO or weighted average, with lots pooled per asset across all wallets
- Checked against Koinly: tooling replays a Koinly export through the same engine and compares the two reports
- Exact decimal maths throughout, in seven languages
