Find and revoke old unlimited token approvals
Intermediate12h1–2
ViemWagmiNext.js
17/20Crypto Tax Transaction CSV
Turn wallet history into a clean CSV with cost basis.
Intermediate14h1–2 people17/20 fit
Build Crypto Tax Transaction CSV for crypto users filing taxes in ~14h with 1–2 people. Stack: Viem + Python + Next.js.
Why it wins: Painful annual problem.
Build flow
01 · Problem
Users spend days reconstructing trades for taxes.
02 · Solution
Fetch wallet history, classify transfers, swaps and income, compute cost basis by a chosen method and export.
03 · Build
- 1Fetch transactions
- 2Classify
- 3Compute basis
- 4Export
04 · Demo
Export a year of activity for a demo wallet.
MVP checklist
- History fetch
- Classification
- Cost basis
- CSV export
Tech stack
| Tech | Role | |
|---|---|---|
| Viem | Ethereum client | Chain |
| Python | Backend / scripting | Backend |
| Next.js | Frontend + API routes | Web |
Reference repos
Open-source projects you can build on. Links checked 2026-10-31.
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