# Upcoming Features ### Use Flexible Fees DOT, aUSD, ACA, RenBTC, AMPL are all first-class fee tokens in Acala EVM, meaning that users can pay transaction fees in any of these tokens. ### Acala DeFi Contracts Acala's DeFi primitives (stablecoin, staking derivative, and DEX) are being made available as pre-compiled contracts, and will be composable inside Acala EVM. Details coming soon. ### State Rent A contract consumes storage on the blockchain, and thus should be charged for simply existing. This ensures that people don't take advantage of "free, unlimited storage". This is not a new concept, there're EIP, pre-EIP and discussions to implement state rent in Ethereum. Parity already implements it in the native smart contract platform [Ink!](https://substrate.dev/docs/en/knowledgebase/smart-contracts/overview#smart-contracts). We now introduce this mechanism in Acala EVM. Details coming soon. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://wiki.acala.network/build/development-guide/smart-contracts/advanced/use-flexi-fee.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.