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<h1 class="page">Development</h1>
<div id="preamble">
<div class="sectionbody">
<div class="paragraph">
<p>This page shares information related to the development of Log4j.
Content is aimed for users who want to contribute source code patches and maintainers.</p>
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<p>Do you need help for setting up or configuring Log4j?
Please refer to <a href="https://logging.apache.org/support.html">the Support page</a> instead.</p>
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<div class="sect1">
<h2 id="github"><a class="anchor" href="#github"></a>GitHub setup</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Log4j uses GitHub extensively:</p>
</div>
<div class="dlist">
<dl>
<dt class="hdlist1">Source code repository</dt>
<dd>
<p><a href="https://github.com/apache/logging-log4j2/tree/rel/2.25.1" class="bare">https://github.com/apache/logging-log4j2/tree/rel/2.25.1</a></p>
</dd>
<dt class="hdlist1">Issue tracker</dt>
<dd>
<p><a href="https://github.com/apache/logging-log4j2/issues" class="bare">https://github.com/apache/logging-log4j2/issues</a></p>
</dd>
<dt class="hdlist1">Discussions</dt>
<dd>
<p><a href="https://github.com/apache/logging-log4j2/discussions" class="bare">https://github.com/apache/logging-log4j2/discussions</a></p>
<div class="admonitionblock tip">
<table>
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<td class="icon">
<i class="fa icon-tip" title="Tip"></i>
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<td class="content">
<div class="paragraph">
<p>Maintainer discussions mostly take place in mailing lists.
Please refer to <a href="https://logging.apache.org/support.html">the Support page</a> for the complete list of communication channels.</p>
</div>
</td>
</tr>
</table>
</div>
</dd>
</dl>
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</div>
<div class="sect1">
<h2 id="branching"><a class="anchor" href="#branching"></a>Branching scheme</h2>
<div class="sectionbody">
<div class="paragraph">
<p>The following branching scheme is followed:</p>
</div>
<div class="dlist">
<dl>
<dt class="hdlist1"><code>2.x</code></dt>
<dd>
<p>The most recent Log4j 2 code</p>
</dd>
<dt class="hdlist1"><code>main</code></dt>
<dd>
<p>The most recent Log4j 3 code</p>
</dd>
<dt class="hdlist1"><code>&lt;sourceBranch&gt;-site-&lt;environment&gt;</code></dt>
<dt class="hdlist1"><code>&lt;sourceBranch&gt;-site-&lt;environment&gt;-out</code></dt>
<dd>
<p>Branches used to serve the staging and production websites.
<code>out</code>-suffixed ones are automatically populated by CI, you are not supposed to touch them.
See <a href="https://logging.apache.org/logging-parent/usage.html#website">the Logging Parent website</a> for details.</p>
</dd>
<dt class="hdlist1"><code>release/&lt;version&gt;</code></dt>
<dd>
<p>Branch triggering the CI logic to start <a href="https://logging.apache.org/logging-parent/release-instructions-project.html">the release process</a></p>
</dd>
</dl>
</div>
</div>
</div>
<div class="sect1">
<h2 id="building"><a class="anchor" href="#building"></a>How can I build the project?</h2>
<div class="sectionbody">
<div class="paragraph">
<p>See <a href="https://github.com/apache/logging-log4j2/tree/rel/2.25.1/BUILDING.adoc">the build instructions</a>.</p>
</div>
</div>
</div>
<div class="sect1">
<h2 id="fuzzing"><a class="anchor" href="#fuzzing"></a>How can I run fuzz tests?</h2>
<div class="sectionbody">
<div class="paragraph">
<p>See <a href="https://github.com/apache/logging-log4j2/tree/rel/2.25.1/FUZZING.adoc">the fuzzing instructions</a>.</p>
</div>
</div>
</div>
<div class="sect1">
<h2 id="contributor"><a class="anchor" href="#contributor"></a>I am <strong>not</strong> a committer. How shall I submit a patch?</h2>
<div class="sectionbody">
<div class="olist arabic">
<ol class="arabic">
<li>
<p>Is this a <em>trivial fix</em> such as code or documentation typo?
Simply submit a pull request.
Changelog entry is not needed and make sure <code>./mvnw verify site</code> succeeds.</p>
</li>
<li>
<p>Is this a <em>non-trivial fix</em> or a <em>new feature</em>?
Pitch it in a <a href="https://logging.apache.org/support.html#discussions-maintainer">maintainer discussion channel</a> and ask for assistance.</p>
</li>
</ol>
</div>
</div>
</div>
<div class="sect1">
<h2 id="committer"><a class="anchor" href="#committer"></a>I am a committer. How shall I push my changes?</h2>
<div class="sectionbody">
<div class="paragraph">
<p>As per <a href="https://lists.apache.org/thread/rx2hgc5mwql06yzwz2j8wkp8z6nmdcqk">the PMC resolution on 2025-04-10</a>, all changes must be submitted in a pull request and undergo peer review.</p>
</div>
<div class="paragraph">
<p>Make sure a changelog entry is attached, and <code>./mvnw verify site</code> succeeds.</p>
</div>
<div class="admonitionblock tip">
<table>
<tr>
<td class="icon">
<i class="fa icon-tip" title="Tip"></i>
</td>
<td class="content">
<div class="paragraph">
<p>You are strongly advised to spar with another maintainer first (see <a href="https://logging.apache.org/support.html#discussions-maintainer">maintainer discussion channels</a>) before starting to code.</p>
</div>
</td>
</tr>
</table>
</div>
</div>
</div>
<div class="sect1">
<h2 id="release-project"><a class="anchor" href="#release-project"></a>I am a PMC member. How do I make a new release?</h2>
<div class="sectionbody">
<div class="paragraph">
<p>All Maven-based Logging Services projects are parented by
<a href="https://logging.apache.org/logging-parent/index.html">Logging Parent</a>,
which streamlines several project-wide processes, including making a new release.
See <a href="https://logging.apache.org/logging-parent/release-instructions-project.html">its release instructions for projects</a>.</p>
</div>
</div>
</div>
<div class="sect1">
<h2 id="release-xml-schema"><a class="anchor" href="#release-xml-schema"></a>I am a PMC member. How do I publish a new XML schema?</h2>
<div class="sectionbody">
<div class="paragraph">
<p>All Maven-based Logging Services projects are parented by
<a href="https://logging.apache.org/logging-parent/index.html">Logging Parent</a>,
which streamlines several project-wide processes, including publishing XML schemas.
See <a href="https://logging.apache.org/logging-parent/release-instructions-xml-schema.html">its release instructions for XML schemas</a>.</p>
</div>
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<div class="paragraph">
<p><strong>Projects and XML schemas have different lifecycles!</strong>
A new release of a project does not necessarily mean a new release of its XML schemas.
XML schemas might have been untouched, or they might contain minor changes while the project itself contains breaking changes, etc.</p>
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var d=document, g=d.createElement('script'), s=d.getElementsByTagName('script')[0];
g.async=true; g.src=u+'matomo.js'; s.parentNode.insertBefore(g,s);
})();
</script>
<noscript><p><img src="https://analytics.apache.org/matomo.php?idsite=42&amp;rec=1" style="border:0;" alt="" /></p></noscript>
<!-- End Matomo Code -->
<script id="site-script" src="./_/js/site.js" data-ui-root-path="./_"></script>
<script async src="./_/js/vendor/highlight.js"></script>
<!-- `@asciidoctor/tabs` extension scripts -->
<script async src="./_/js/vendor/tabs.js"></script>
</body>
</html>