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kotlinlang

Is there a solid step by step guide on how to solve this build error?
```
Runtime JAR files in the classpath should have the same version.
```

For the life of me I can't find what's pulling in the wrong version of stdlib.

try running the gradle "dependencies" task on your project and find where the two versions come from

I am using Maven and yeah running `dependency:analyze` did not really help me. It just says that the dependency is undeclared but somehow it's there.

no, running `dependency:analyze` but I will try `tree`

the next question is, how do I get rid of it.. I need the dependency but it's pulling in an old version of kotlin

is there another option than adding `&lt;exclusion&gt;`?

i thought if I declare it specifically in my module it should take precedence over this.. well I declared it in the parent of this pom, but that should work too I thought

Fixed it!
I had `stdlib-jre8` declared explicitely but I also had to declare `stdlib`.

Now someone could explain to me how Kotlin is packaged and what does it mean to use `stdlib-jre8` vs `stdlib`

I believe stdlib-jre8 is compiled with bytecode targeting Java 8 rather than Java 6.

`kotlin-stdlib-jre8` is an additional artifact for `kotlin-stdlib` with java 8 specific API. 
You need to have both in runtime if you want to use `kotlin-stdlib-jre8`.
Usually `kotlin-stdlib` and `kotlin-stdlib-jre7` are pulled in as transitive dependencies of  `kotlin-stdlib-jre8`

Thanks for clarifying :slightly_smiling_face: