ExperimentalTestnet: compiles and runs (CLI), experimentalMainnet: Not availableSoftware: Fe 26.5.1 (149c758)Updated 2026-11-08

Fe (experimental)

Experimental

Fe is a research language whose syntax and compiler change between releases. PQWERAI treats it as experimental until compiler maturity, stable tooling and a security review gate pass. Do not deploy value-bearing Fe contracts.

Compiler	Fe 26.5.1 (149c758); Windows exe SHA-256 7fe5339c…85d5f
Output	out/<Contract>.bin, .runtime.bin, .abi.json
Status	🧪 Counter compiles, deploys and runs on chain 77240 (CLI). No events in the example.

Example

Counter.fe

// Starter counter (Fe 26.5.1, EXPERIMENTAL). Unaudited example.
use std::abi::sol

msg CounterMsg {
    #[selector = sol("increment()")]
    Increment,
    #[selector = sol("get()")]
    Get -> u256,
}

struct CounterStore {
    value: u256,
}

pub contract Counter {
    mut store: CounterStore

    init() uses (mut store) {
        store.value = 0
    }

    recv CounterMsg {
        Increment uses (mut store) {
            store.value = store.value + 1
        }

        Get -> u256 uses (store) {
            store.value
        }
    }
}

Build and deploy

fe build --standalone Counter.fe              # writes out/Counter.bin, out/Counter.runtime.bin, out/Counter.abi.json
TX=$(cast send --async --keystore "$KEYSTORE" --password-file "$PASSWORD_FILE" --rpc-url "$RPC" --create "0x$(cat out/Counter.bin)")
cast receipt "$TX" contractAddress --rpc-url "$RPC"

Measured: 99 runtime bytes, 77,010 deployment gas, 43,304 gas for increment().

Caveats

• Language semantics may change in the next release; pin the compiler and keep the exact version with your sources.
• Few auditors and analysis tools support Fe.
• The ABI JSON comes from the compiler's msg selectors; check it against the selectors you expect.

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Sources at 72057fe3ec: developers/examples/languages/Counter.fe · architecture/MULTILANGUAGE_CONTRACTS.md

Found a problem? Report a documentation issue · Build testnet-rc1+72057fe3ec