M Extension Framework is a modular templates of ERC-20 stablecoin extensions that wrap the yield-bearing $M token into non-rebasing variants for improved composability within DeFi. Each extension manages yield distribution differently and integrates with a central SwapFacility contract that acts as the exclusive entry point for wrapping and unwrapping.
All contracts are deployed behind transparent upgradeable proxies (by default).
Each extension inherits from the abstract MExtension base contract, which defines shared wrapping logic. Only the SwapFacility is authorized to call wrap() and unwrap(). Yield is accrued based on the locked $M balance within each extension and minted via dedicated yield claim functions.
-
MYieldToOne- All yield goes to a single configurable
yieldRecipient - Includes a blacklist enforced on all user actions
- Handles loss of
$Mearner status gracefully
- All yield goes to a single configurable
-
MEarnerManager- Redistributes yield to all holders minus per-address
feeRate - Enforces a whitelist; non-whitelisted users are frozen and yield is redirected as fee
- Yield is claimed via
claimFor(address) - Does not handle loss of
$Mearner status, leading to potential insolvency if not upgraded
- Redistributes yield to all holders minus per-address
-
MYieldFee- All users receive the same yield rate, discounted by a global
feeRate - Yield can be redirected via
claimRecipientper user - Includes
updateIndex()to resync with new$Mrates - Can handle loss and regain of
$Mearning status viadisableEarning()andenableEarning()
- All users receive the same yield rate, discounted by a global
-
MSpokeYieldFee- Optimized for EVM sidechains (e.g., Arbitrum, Optimism)
- Index updates occur via bridging, not time-based growth
- Uses an external
rateOraclefor fee calculation - Inherits most behavior from
MYieldFee
The SwapFacility contract acts as the exclusive router for all wrapping and swapping operations involving $M and its extensions.
swap()– Switch between extensions by unwrapping and re-wrappingswapInM(),swapInMWithPermit()– Accept$Mand wrap into the selected extensionswapOutM()– Unwrap to$M(restricted to whitelisted addresses only)
All actions are subject to the rules defined by each extension (e.g., blacklists, whitelists)
A helper contract that enables token swaps via Uniswap V3.
- Immutable and admin-controlled
- Uses Uniswap's
SwapRouter02 - Functions:
swapIn(path, ...)swapOut(path, ...)
- Supports multi-hop paths or single-hop with default 0.01% fee
- Token whitelist is controlled via
DEFAULT_ADMIN_ROLE
| Chain | Address |
|---|---|
| Ethereum | 0x023bd2F0A95373C55FC8D1c5F8e60cC3B9Bc4f4b |
| Arbitrum | 0x023bd2F0A95373C55FC8D1c5F8e60cC3B9Bc4f4b |