A modern Kotlin script runner

Run .kts like you
run modern scripts.

What uv is for Python and bun is for JavaScript, ktx aims to be for .kts. Daemon-warm starts, lockfiles, per-script JDK, and a one-command compile-to-fat-jar — built on top of JetBrains' supported kotlin-main-kts.

Get started

$mise use -g github:gaojunran/ktx@latest

7.3×: faster than main-kts warm
6.8×: faster on the dev loop
13 MB: standalone jar from ktx compile

01daemonA warm Kotlin compiler. The daemon keeps the embedded compiler resident across runs, so repeat invocations land at ~120 ms — not the multi-second cost of spinning up a fresh JVM and PSI/FIR every time. Daemon mode →02lockfilesReproducible scripts.ktx lock writes *.kts.lock pinning every transitive jar to its sha256. ktx run --frozen runs offline, makes CI deterministic. Lockfiles →03toolchainPer-script JDK. Declare @file:Toolchain(jdk = "17") and ktx auto-installs the requested JDK from Adoptium and re-execs onto it before compilation. Toolchain →04compileDistribute as a single jar.ktx compile emits a 11–13 MB fat jar that runs on plain JRE 17+ — your end users do not need ktx, do not need a Kotlin compiler, do not need anything but Java. Compile →

Run .kts like you run modern scripts.

Run .kts like you
run modern scripts.