Add bithoven

[ChrisCho-H]

Bithoven is a type-safe, developer-friendly programming language designed to compile down to native Bitcoin Script. It bridges the gap between complex smart contract logic and the low-level stack machine of the Bitcoin Virtual Machine (VM).

Key features are following:

• Imperative Syntax: Write logic using familiar if, else, and return statements instead of mental stack juggling.
• Type Safety: First-class support for bool, signature, string, and number types to prevent common runtime errors.
• Multiple Spending Paths: Define complex contracts (like HTLCs) with distinct execution branches and input stack requirements.
• Targeted Compilation: Support for legacy, segwit, and taproot compilation targets via pragmas.
• Native Bitcoin Primitives: Built-in keywords for timelocks (older, after), cryptography (sha256, checksig), and verification (verify).

repo: https://github.com/ChrisCho-H/bithoven
cargo: https://crates.io/search?q=bithoven

You can try it in the browser here (runs via WASM): https://bithoven-lang.github.io/bithoven/ide/

Here is an example of a Hashed Time-Locked Contract (HTLC):

pragma bithoven version 0.0.1;
pragma bithoven target segwit;

/* * Stack Input Definitions
 * Each line defines a valid input stack configuration for a spending path.
 */
(condition: bool, sig_alice: signature)
(condition: bool, preimage: string, sig_bob: signature)

{
    // If 'condition' is true, we enter the Refund Path (Alice)
    if condition {
        // Enforce relative timelock of 1000 blocks
        older 1000;

        // If timelock is satisfied, Alice can spend with her signature
        return checksig(sig_alice, "0245a6b3f8eeab8e88501a9a25391318dce9bf35e24c377ee82799543606bf5212");

    } else {
        // Redeem Path (Bob)
        // Bob must reveal the secret preimage that hashes to the expected value
        verify sha256 sha256 preimage == "53de742e2e323e3290234052a702458589c30d2c813bf9f866bef1b651c4e45f";

        // If hash matches, Bob can spend with his signature
        return checksig(sig_bob, "0345a6b3f8eeab8e88501a9a25391318dce9bf35e24c377ee82799543606bf5212");
    }
}

Thanks for maintaining this list!