# d-xo/weird-erc20

weird erc20 tokens

Repository: https://github.com/d-xo/weird-erc20
Canonical: https://ross.abutalabs.com/products/weird-erc20
Language: Solidity
License Family: other
Last push: 2025-06-03T10:39:47+00:00

## Health v2 (maintenance only)
Score: 43/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 24, release rhythm 35, longevity 100
- inputs: {"age_days": 2200, "days_push": 456, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases, no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1707, forks 219 (observed 2026-08-28T04:05:25.424062+00:00)

## What it is
A collection of minimal Solidity implementations of ERC20 tokens with unusual or non-standard behavior, based on real tokens that have been exploited in the wild. It serves as a reference for smart contract developers and auditors to understand and test against edge cases in ERC20 token implementations.

## Use cases
- test my smart contract against weird ERC20 token behaviors
- learn about ERC20 edge cases and non-standard token implementations
- audit a DeFi protocol for token integration vulnerabilities
- find examples of reentrant ERC20 tokens
- understand why USDT doesn't return a bool on transfer
- build defensive token integration code
- create mock tokens for fuzzing and testing

## When to choose
- you are developing or auditing smart contracts that interact with arbitrary ERC20 tokens
- you need realistic mock tokens for testing contract robustness
- you want to learn about historical ERC20 exploits and pitfalls

## When to avoid
- you need a production-ready ERC20 token to deploy
- you are looking for a token integration checklist rather than example implementations
- you need a fully-featured testing framework rather than reference examples

## Facets
- artifact type: learning-resource
- maturity: active
- function: security, testing, developer-tools
- domain: security, blockchain, developer-tools, tutorials
- platform: -
- tags: erc20, smart-contracts, solidity, token-security, audit, blockchain, edge-cases, ethereum

## Member repositories
- d-xo/weird-erc20 (main) score 43

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:05:25.424062+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T03:37:26.095864+00:00, confidence not recorded.
  - readme: https://github.com/d-xo/weird-erc20 (fetched 2026-08-28T04:05:25.424062+00:00, sha ac18445d0833)
- Data as of 2026-08-30T08:39:29.467469+00:00.