Gradle "Could not resolve org.jetbrains.kotlin:kotlin-stdlib" in CI

By Daniel Zoghalchali·Latchkey

The Kotlin plugin adds kotlin-stdlib for you. A "Could not resolve" error means Gradle cannot fetch the requested stdlib version: mavenCentral is missing from repositories, the runner has no network to it, or a forced version conflicts with the plugin version.

What this error means

Dependency resolution fails with "Could not resolve org.jetbrains.kotlin:kotlin-stdlib:1.9.25" (or a "Conflict(s) found for the following module") pointing at the stdlib.

> Could not resolve org.jetbrains.kotlin:kotlin-stdlib:2.0.21.
  Required by:
      project :app
  > Could not resolve org.jetbrains.kotlin:kotlin-stdlib:2.0.21.
    > No cached version available for offline mode

Diagnose it: get the real failure out of Gradle

Gradle summarises failures aggressively, and the top-level message frequently describes a downstream symptom rather than the cause. Re-run the failing task with diagnostics before changing build logic.

# the actual stack, plus what Gradle decided about the build
./gradlew <task> --stacktrace --info

# is a stale daemon or cache involved?
./gradlew --stop
./gradlew <task> --no-daemon --no-build-cache

# what does Gradle think the environment is?
./gradlew -version

Common causes

The repository serving the stdlib is not declared

Without mavenCentral() (or an internal mirror) in repositories {}, Gradle has nowhere to fetch the stdlib on a clean CI runner.

A forced stdlib version conflicts with the plugin

A resolution rule or BOM forces a stdlib version different from what the Kotlin plugin expects, so Gradle cannot agree on one.

How to fix it

Declare the repository

1. Ensure mavenCentral() (or your mirror) is in repositories {}.
2. Remove --offline if the runner has no populated cache.
3. Re-run resolution to fetch the stdlib.

repositories {
    mavenCentral()
}

Let the plugin manage the stdlib version

Do not force a stdlib version; align it with the Kotlin plugin so the two never conflict.

dependencies {
    // no explicit kotlin-stdlib pin; the kotlin("jvm") plugin adds the matching version
}

Configuration cache and CI

• The configuration cache rejects build logic that reads mutable state at execution time, which is why enabling it surfaces errors an existing build never showed.
• Run with --configuration-cache-problems=warn first to see the full list rather than failing on the first one.
• A cached configuration keyed to a different environment is worse than none. Include the JDK version in your cache key.

How to prevent it

• Keep a resolvable repository declared for every project in CI.
• Avoid forcing kotlin-stdlib; let the plugin choose the matching version.
• Cache the Gradle dependency cache so offline resolution has the stdlib available.

Frequently asked questions

Related guides

References

• Apache Maven guides
• Gradle user manual
• GitHub Actions documentation