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<p>OpenPorte is a community-maintained fork of the ALTCHA Spam Protection<br />
plugin for WordPress (version 1), which provides a free, open source,<br />
self-hostable, privacy-friendly CAPTCHA alternative based on a proof-<br />
of-work mechanism — no cookies, no tracking, GDPR-friendly by design.</p>
<p>For the list of contributors, refer to our GitHub project: <a href="https://github.com/jcberthon/openporte/graphs/contributors?from=1.6.2024" rel="nofollow ugc">Contributors</a>.</p>
<h4>Background</h4>
<p>The original ALTCHA WordPress plugin (v1) was open source (GPLv2). Its<br />
authors have since released a version 2/3 which is no longer open source,<br />
and some features that were free in v1 are now paid. They no longer<br />
maintain v1 and recommend that users migrate to v2/v3. See the official<br />
project at https://altcha.org for their offering.</p>
<p>OpenPorte continues the v1 line as free software (GPLv2 or later) for users<br />
who want to stay on a fully open-source, self-hosted solution. It is a<br />
faithful fork: existing v1 installations can switch to OpenPorte and keep<br />
their settings (see Upgrading).</p>
<h4>Compatibility</h4>
<p>OpenPorte is backward-compatible with ALTCHA v1:</p>
<ul>
<li>Your existing settings are migrated automatically on activation.</li>
<li>The <code>[altcha]</code> shortcode keeps working (alongside the new <code>[openporte]</code>).</li>
<li>The <code>altcha_*</code> filters and actions keep firing as deprecated aliases.</li>
</ul>
<p>See the Deprecations section for the full list of compatibility aliases and<br />
what they map to.</p>
<h3>Upgrading</h3>
<h4>From the original ALTCHA v1 plugin</h4>
<p>Deactivate the old ALTCHA plugin, then install and activate OpenPorte. Your<br />
existing configuration is detected and copied into the OpenPorte settings on<br />
first activation; the original ALTCHA settings are left untouched, so you can<br />
roll back to ALTCHA v1 without losing anything. Do not run both plugins at the<br />
same time.</p>
<h3>Deprecations</h3>
<p>The following ALTCHA-era identifiers are kept as aliases for backward<br />
compatibility and are scheduled for removal in a future release:</p>
<ul>
<li>The <code>[altcha]</code> shortcode — use <code>[openporte]</code>.</li>
<li>The <code>altcha/v1</code> REST namespace — use <code>openporte/v1</code>.</li>
<li>The <code>altcha_*</code> filters and actions — now firing through WordPress’ deprecated<br />
hook mechanism; use the <code>openporte_*</code> equivalents.</li>
<li>The <code>AltchaPlugin</code> class and the <code>ALTCHA_VERSION</code> / <code>ALTCHA_WIDGET_VERSION</code><br />
constants — use <code>OpenPortePlugin</code> and the <code>OPENPORTE_*</code> constants.</li>
<li>Integrations targeting paid-only third-party plugins; affected users should<br />
migrate to the official ALTCHA v2/v3 plugin.</li>
</ul>
<h3>Privacy</h3>
<h4>No cookies, no tracking</h4>
<p>OpenPorte prioritizes user privacy by avoiding the use of cookies and fingerprinting techniques.</p>
<h4>No external service</h4>
<p>This plugin remains fully contained within your WordPress installation, eliminating any reliance on external services.</p>
<h3>Modes of Operation</h3>
<p>OpenPorte verifies submissions in one of two modes, selected in the settings<br />
(API Mode):</p>
<ul>
<li>Self-hosted (default) — a proof-of-work challenge is issued and verified by<br />
your own WordPress site through the REST API. Fully self-contained, with no<br />
external service and no additional setup beyond enabling the integrations you<br />
need.</li>
<li>Custom — point the Challenge URL at your own ALTCHA-compatible backend (for<br />
example a self-hosted ALTCHA Sentinel). Submissions are verified with your<br />
site’s signing secret.</li>
</ul>
<p>The paid altcha.org regional SaaS classifier offered by earlier versions has<br />
been removed; both remaining modes are free and self-hostable.</p>
<h3>REST API</h3>
<p>This plugin requires the WordPress REST API. If you are using any “Disable REST API” plugins, ensure that the endpoint <code>/altcha/v1/challenge</code> (marked for deprecation) and <code>/openporte/v1/challenge</code> are allowed.</p>
<h3>Supported Integrations</h3>
<ul>
<li>CoBlocks</li>
<li>Contact Form 7</li>
<li>Elementor Pro Forms (deprecated — paid plugin, see Deprecations)</li>
<li>Formidable Forms</li>
<li>Forminator</li>
<li>GravityForms</li>
<li>HTML Forms</li>
<li>WPDiscuz</li>
<li>WPForms</li>
<li>WP-Members</li>
<li>WordPress Login, Register, Password reset</li>
<li>WordPress Comments</li>
<li>WooCommerce</li>
<li>Custom HTML (via the <code>[openporte]</code> shortcode, or the deprecated <code>[altcha]</code> alias)</li>
</ul>
<h3>Source Code</h3>
<p>All source code for the plugin, and the ALTCHA widget is available on GitHub. In the repository, you’ll also find versions of non-minified JavaScript and CSS assets:</p>
<ul>
<li>Plugin: https://github.com/jcberthon/openporte</li>
<li>ALTCHA Widget: https://github.com/altcha-org/altcha</li>
</ul>


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