This document lists the changes between Vespa major versions 8 and 9. As documented in Vespa versions, new functionality in Vespa is introduced in minor versions, while major versions are used to mark releases breaking compatibility. As Vespa 9 does not introduce any new functionality, it is as safe and mature as the versions of Vespa 8 preceding it.
Note: This is work in progress, Vespa 9 is tentatively planned for release in Q1 2026.
The compatibility breaking changes in Vespa 9 fall into these categories:
To ensure their applications are compatible with Vespa 9, application owners must:
Usage of deprecated Java APIs produce warnings during compilation, while deployment warnings are produced for application package deprecations and most changes to the container runtime environment. In hosted Vespa or Vespa Cloud, deployment warnings are shown in the application's console view. However, for other types of changes, there is no way to emit deprecation warnings, so these are only described in this document and other Vespa documentation.
The following sections lists all the changes from Vespa 8 to Vespa 9 in detail.
These changes may break clients, and impact both performance and user experience. Applications that are in production and relies on these defaults should make configuration changes to keep the existing behavior when upgrading to Vespa 8. This can be done on Vespa 8, before upgrading - using bucket tests can be useful.
The following defaults have changed:
| Change | Configuration required to avoid change on Vespa 9 |
|---|
The following settings are removed from schema:
| Name | Replacement |
|---|
The following elements and attributes in services.xml have new semantics:
| Name | Description |
|---|
The following elements and attributes are removed from services.xml:
| Parent element | Removed construct | Description |
|---|
Schemas should now be placed in the schemas/ folder.
| Package | Description |
|---|
Classes and methods that were marked as deprecated in Vespa 8 are removed. If deprecation warnings are emitted for Vespa APIs when building the application, these must be fixed before migrating to Vespa 9. The sections below contain only the most notable changes.
The following classes are no longer public API and have been moved to Vespa internal packages:
| Package | Class | Migration advice |
|---|---|---|
| com.yahoo.search.predicate | PredicateIndex + related classes | The Predicate Search Java Library is removed (com.yahoo.vespa:predicate-search). Use predicate fields in Vespa instead. |
The following methods are removed:
| Method | Migration advice |
|---|
The Javadoc of the deprecated types/members should document the replacement API. The below list is not exhaustive - some smaller and trivial changes are not listed.
| Type(s) | Description |
|---|
A few redundant APIs have been deprecated because they have replacements that provide the same, or better, functionality. We advise you switch to the replacement to reduce future maintenance cost.
| Type(s) | Replacement |
|---|
Vespa 9 upgrades the JDK version from 17 to 25. Java artifacts built against older JDK versions will still be compatible with Vespa 9 (JDK 25). The opposite will not be possible - Vespa 8 (JDK 21) is not compatible with newer JVM byte code. It's possible though to use the --release option for javac to target an older JDK version.
The following Maven artifacts are no longer provided runtime to user application plugins by the Jdisc container:
| Artifact | Notes |
|---|
Make sure your application OSGi bundle embeds the required artifacts from the above list.
An artifact can be embedded by adding it in scope compile to the dependencies section in pom.xml.
Typically, these artifacts have until now been used in scope provided.
Use mvn dependency:tree to check whether any of the listed artifacts are directly or transitively included
as dependencies.
As always, remove any dependencies that are not required by your project. Consult the Maven documentation on Dependency Exclusions for how to remove a transitively included dependency.
An example adding org.json:json as a compile scoped dependency:
<dependencies>
...
<dependency>
<groupId>org.json</groupId>
<artifactId>json</artifactId>
<version>20211205</version>
<scope>compile</scope>
</dependency>
...
</dependencies>
The following HTTP API parameters are removed from the query API:
| Standard API path | Parameter name | Replacement |
|---|
The following metrics are renamed:
The following metrics are removed:
Vespa can calculate and return all rank-features
in the rankfeatures summary field. Vespa 9 contains some changes to this list:
See upgrade procedure for how to upgrade.