Rust-style error handling for Kotlin.

AnyhowKt is a Kotlin Multiplatform (KMP) library inspired by Rust's anyhow crate. It provides a simple, powerful, and expressive way to handle errors with:

• Context-aware errors
• Short-circuiting with bind() (Rust ?-like behavior)
• Typed and untyped error sources
• bail, ensure, and structured error propagation
• Works across JVM, Android, iOS, JS, Native

• Rust-like anyhow { } result builder
• bind() for early-return error propagation (Rust ?)
• .context() and withContext() for rich error messages
• bail() for immediate failure
• ensure() / ensureNotNull() helpers
• Convert Kotlin Result to AnyhowResult
• Typed + string + throwable errors

sourceSets {
    commonMain.dependencies {
        implementation("io.github.itsvks19:anyhowkt:<version>")
    }
}

dependencies {
    implementation("io.github.itsvks19:anyhowkt:<version>")
}

val result = anyhow {
    val a = parseInt("10").bind()
    val b = parseInt("20").bind()
    a + b
}

val value: Int = result.unwrap()

Rust:

let value = compute()?;

Kotlin (AnyhowKt):

val value = compute().bind()

This works inside anyhow { } blocks.

val result = anyhow {
    val file = readFile("config.json")
        .anyhowResult { "file not found" }
        .bind() // Early return on readFile failure

    parseConfig(file)
        .anyhow()
        .bind()
}.context("Failed to load application config")

Error output becomes:

Failed to load application config
Caused by: file not found
...

val result = anyhow {
    if (user == null) {
        bail("User not found")
    }
    user.name
}

anyhow {
    ensure(x > 0) { "x must be positive" }
    ensureNotNull(user) { "user is required" }
    ensureEquals(a, b) { "values must match" }
}

val kResult: Result<Int> = runCatching { riskyCall() }

val result: AnyhowResult<Int> = kResult.anyhow()

This library internally uses arrow-kt.

If you are using an IntelliJ IDEA or any other IDE from JetBrains, we strongly recommend installing the Arrow plug-in. The plug-in helps fix common problems, especially in the realm of typed errors and suggests more idiomatic alternatives when available.

MIT License.

PRs and feature requests are welcome! If you'd like to help add:

• richer formatting
• better JS/iOS backtraces
• or compiler plugin support

feel free to contribute ✨