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Azul Zulu Versioning and Naming Conventions

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This section explains the naming convention and versioning schemes for Azul Zulu binary packages.

Versioning Scheme

For historical reasons, Azul Zulu releases use different versioning schemes for different major versions. For Azul Zulu 8 and earlier, the version consists of 4 numbers: XX.YY.0.BB, the third number is always "0". For Azul Zulu 11 and later, the version consists of 3 numbers: XX.YY.BB.

Terms

The following terms are used on this page.

Distribution types

  • Subscriber Availability (SA): tested, certified, and commercially supported Azul Zulu Builds of OpenJDK. SA builds may support configurations and features that are unavailable to free users.

  • Community Availability (CA): Azul Zulu Builds of OpenJDK that are free to download and use.

  • Non-Verified (NV): builds that are not verified. Azul no longer provides these configurations.

Release types

  • CPU (Critical Patch Update): contains fixes to security vulnerabilities and critical bug fixes. CPU releases are generally based on prior-cycle PSU releases, with only security fixes applied. They provide a low-risk vehicle for the potentially urgent deployment of security fixes. CPU releases are available in SA distributions.

  • PSU (Patch Set Update): incorporates all fixes of the corresponding CPU, plus additional non-security bug fixes that align the release contents with the associated OpenJDK quarterly release. PSU releases are available in SA and CA distributions.

  • Quarterly update release: the regular CPU or PSU release published every quarter. The CPU-based and the PSU-based releases together form the CPU line and the PSU line.

  • CSPU (Critical Security Patch Update): contains fixes to critical issues and security vulnerabilities, delivered monthly between the quarterly update releases. A CSPU for CPU is applied to the latest quarterly CPU release, a CSPU for PSU to the latest quarterly PSU release.

  • Out-of-cycle update: an update release published outside the regular quarterly schedule, based on a quarterly CPU or PSU release. It contains the content of that release, any CSPU fixes released since then for the same package types, any earlier out-of-cycle update content, and the fix described in the "What’s New" section of the release notes.

  • BPR (Bundled Patch Release): a release that bundles additional patches on top of a quarterly update release or a CSPU.

  • FVB (Fix Verification Bundle): a bundle for verifying a specific fix.

Note
 Up to and including the July 2026 release, the release version was defined by the major and minor version (first two numbers, XX.YY). Since the August 2026 release, the minor version advances only at a quarterly update release. A quarterly update release and the CSPUs that follow it in the same quarter therefore share one XX.YY, and are told apart by the build number (BB). The build number is part of the version rather than metadata: zulu25.35.214 is a complete version.

Starting with the August 2026 release, Azul publishes monthly CSPUs in between the quarterly update releases, aligned with the OpenJDK releases. A CSPU keeps the major and minor version (XX.YY) of the quarterly update release it is based on, and is identified by its build number (BB). Both the CPU-based and the PSU-based release line of that quarter receive a CSPU.

Version Format

As of April 2021 release, the Azul Zulu versions use the following scheme:

Azul Zulu Major Version Full Version Format

8 and earlier

XX.YY.0.BB

11 and later

XX.YY.BB

The following table explains the meaning of XX, YY, and BB.

XX

The major version.

YY

The minor version.

  • even numbers indicate a PSU release

  • odd numbers indicate a CPU release

BB

The build number.

  • even numbers indicate a Subscriber Availability (SA) bundle

  • odd numbers indicate a Community Availability (CA) or Non-Verified (NV) bundle

  • an SA build number is always its CA counterpart plus one. The lowest pair in a block is therefore x01 (CA) and x02 (SA). Releases that are available only as SA, such as those on the CPU line, start at x02.

  • an out-of-cycle update raises the build number by two, which keeps it on the same distribution

  • BB ≥ 1000 indicate FVB (Fix Verification Bundle) bundles

Starting with the August 2026 release, the remaining build numbers are grouped in blocks of one hundred. The block a build number falls in identifies which update release of the quarter the bundle belongs to, and the blocks apply identically to the CPU and the PSU line:

  • 100-150: the quarterly update release. 151-199 are reserved for its BPR bundles.

  • 200-250: the first CSPU of the quarter. 251-299 are reserved for its BPR bundles.

  • 300-350: the second CSPU of the quarter. 351-399 are reserved for its BPR bundles.

Build numbers below 100 are no longer used. They applied up to and including the July 2026 release.

Note
 Based on building and testing results, the build number can be different within a release, typically grouping different platforms.

Versioning Examples

  • 8.97.0.108 - Azul Zulu 8, an SA bundle of a regular quarterly CPU release

  • 8.98.0.105 - Azul Zulu 8, a CA bundle of a regular quarterly PSU release

  • 8.98.0.106 - Azul Zulu 8, an SA bundle of a regular quarterly PSU release

  • 8.54.0.56 - Azul Zulu 8, an SA bundle of a PSU-based bundled patch release (BPR)

  • 8.54.0.1018 - Azul Zulu 8, an SA fix verification bundle (FVB) for a PSU release

  • 11.91.108 - Azul Zulu 11, an SA bundle of a regular quarterly CPU release

  • 11.92.105 - Azul Zulu 11, a CA bundle of a regular quarterly PSU release

  • 11.92.106 - Azul Zulu 11, an SA bundle of a regular quarterly PSU release

  • 13.39.15 - Azul Zulu 13, an NV bundle of a regular CPU release

  • 15.32.54 - Azul Zulu 15, an SA bundle of a PSU-based bundled patch release (BPR)

  • 11.48.1004 - Azul Zulu 11, an SA fix verification bundle (FVB) for a PSU release

  • 8.95.0.204 - Azul Zulu 8, an SA bundle of the first CSPU based on the July 2026 CPU release

  • 8.96.0.205 - Azul Zulu 8, a CA bundle of the first CSPU based on the July 2026 PSU release

  • 8.96.0.206 - Azul Zulu 8, an SA bundle of the first CSPU based on the July 2026 PSU release

  • 11.90.206 - Azul Zulu 11, an SA bundle of the first CSPU based on the July 2026 PSU release

  • 25.35.252 - Azul Zulu 25, an SA bundle of a BPR of the first CSPU based on the July 2026 CPU release

Bundle Name Convention

Azul Zulu uses a naming convention that encodes relevant information about a bundle into the bundle name. For example:

 
zulu15.31.14-sa-jre15.0.2.0.101-linux_musl_x64.tar.gz

The following table details most common components that make up a name of downloadable Azul Zulu package.

Bundle name part Description

zulu15.29.14-sa-jdk15.0.2-linux_x64.tar.gz

Azul Zulu Version. See Versioning Scheme for details.

zulu15.29.14-sa-jdk15.0.2-linux_x64.tar.gz

Distribution type (SA, CA, NV):

  • sa - Subscriber Availability: These configurations are available only to Azul customers.

  • ca - Community Availability: These configurations are typically available for free download.

  • nv - "Non-Verified" builds: Azul no longer provides these configurations.

zulu15.29.14-sa-jdk15.0.2-linux_x64.tar.gz

Java functionality included in the bundle:

  • jdk - Java Development Kit

  • jre - Java Runtime Environment

  • hl - Headless version of a JDK or JRE (without GUI components)

  • fx-jdk - JDK with JavaFX support

  • fx-jre - JRE with JavaFX support

zulu15.29.14-sa-jdk15.0.2-linux_x64.tar.gz

Java update version

zulu15.29.14-sa-jdk15.0.2-linux_x64.tar.gz

OS family: linux, linux_musl, win, macosx, solaris, qnx

zulu15.29.14-sa-jdk15.0.2-linux_x64.tar.gz

CPU architecture: x64, i686, i386, amd64, aarch64, aarch32sf, aarch32hf, ppc64, ppc32hf, ppc32spe, mips32sf
Note
 Please note that Azul does not build bundles for all possible combinations of the values provided in the table above. Rather, you can use this table to understand what is included in a specific bundle.

There are additional optional suffixes that may appear in the name of a bundle. For example:

 
zulu8.54.0.22-sa-cp2-embvm-jre8.0.292-c2-linux_ppc64.tar.gz

Below is a description of the additional suffixes:

Suffix Description

beta or ea

Early Access bundles.

Both SA and CA distributions may contain Early Access builds noted with -beta- or -ea- in their filename. Early Access builds may not be TCK (Technology Compatibility Kit) certified.

embvm

The bundle is built with the JAVASE_EMBEDDED option. Bundles with this suffix were discontinued in October 2021.

cp1, cp2, or cp3

One of the Java SE Embedded Compact profiles. Read more about compact profiles at https://foojay.io/pedia/compactprofiles/.

c2

Used only with bundles for the ARM 32-bit architecture. Indicates that the bundle contains both Client and Server HotSpot JIT compilers. ARM 32-bit architecture bundles that don’t have this suffix, contain only the Client compilers.

criu

Bundles with the checkpoint/restore functionality.

cr

Bundles with the CRaM (Checkpoint / Restore at Main) functionality.

crac

Bundles with the CRaC (Coordinated Restore at Checkpoint) functionality.

gcc9

Bundles compiled with the GCC 9 toolchain.