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        <title>FLAT – FLAT</title>
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        <h1 id="flat">FLAT<a class="anchor" href="#flat"> # </a></h1>
<p><em>FLAT</em> - the “Frontend Layer API Toolkit” by <a href="https://www.avenga.com/" class="external" target="_blank">Avenga</a> is designed
for easy decoupling frontend from backend in modern web applications.</p>
<p>FLAT is based on well-known <a href="Licenses.html">Open Source Software</a>.
<a href="CHANGELOG.html">Releases</a> are available as <a href="administration/docker.html">Docker images</a>.</p>
<p>This documentation helps building maintainable JSON-based web APIs on
top of FLAT.</p>
<h2 id="tutorial"><a href="tutorial/README.html">Tutorial</a><a class="anchor" href="#tutorial"> # </a></h2>
<p>Create your first FLAT application hands-on and learn the basics in the <a href="tutorial/README.html">Tutorial</a>.
This is the best place to start.</p>
<h2 id="cookbook"><a href="cookbook/README.html">Cookbook</a><a class="anchor" href="#cookbook"> # </a></h2>
<p>Browse the recipes in <a href="cookbook/README.html">FLAT’s Cookbook</a> to learn
how to accomplish common API development tasks with FLAT. Developers will find plenty of examples here.</p>
<h2 id="reference"><a href="reference/README.html">Reference</a><a class="anchor" href="#reference"> # </a></h2>
<p>Look up detailed usage information about FLAT’s nuts and bolts in the <a href="reference/README.html">Reference</a>.</p>
<h2 id="administration"><a href="administration/README.html">Administration</a><a class="anchor" href="#administration"> # </a></h2>
<p>Learn how to deploy and run FLAT APIs in the <a href="administration/README.html">Administration</a> section.</p>
<h2 id="changelog"><a href="CHANGELOG.html">Changelog</a><a class="anchor" href="#changelog"> # </a></h2>
<p>See information about released features in the <a href="CHANGELOG.html">Changelog</a>.</p>

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<li><details><summary><a href="reference/templating/README.html">JSON Templates</a></summary><ul><li><a href="reference/templating/oxn.html">OXN</a></li>
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<li><a href="reference/templating/variable.html">Variable Definition {{$<name> := <expression> }}</a></li>
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<li><details><summary><a href="reference/openapi/README.html">OpenAPI Integration</a></summary><ul><li><a href="reference/openapi/routing.html">Routing</a></li>
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<li><details><summary>Cookbook</summary><ul><li><a href="cookbook/x-flat-jwt.html">Protecting Access using JWT Tokens</a></li>
<li><a href="cookbook/checking-jwt-tokens.html">Performing Additional Checks on JWT Access Tokens</a></li>
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<li><a href="cookbook/forward-request-upstream.html">Forwarding a Request to an Upstream API (cookbook/Flow)</a></li>
<li><a href="cookbook/pass-header-field-upstream.html">How can I pass an arbitrary header field to an upstream system?</a></li>
<li><a href="cookbook/pass-header-field-downstream.html">How can I pass response headers to the client?</a></li>
<li><a href="cookbook/request-timeout.html">How can I increase the request timeout to deal with a slow upstream system?</a></li>
<li><a href="cookbook/upstream-post-requests.html">Sending POST requests</a></li>
<li><a href="cookbook/jwt.html">Signing JWT</a></li>
<li><a href="cookbook/see-client-request.html">How can I inspect the client request?</a></li>
<li><a href="cookbook/swagger-docs.html">Auto Docs with Swagger UI</a></li>
<li><a href="cookbook/builtin-mocking.html">Using the Built-in Mocking</a></li>
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<li><details><summary><a href="tutorial/README.html">Tutorial</a></summary><ul><li><a href="tutorial/README.html#tools">Tools</a></li>
<li><a href="tutorial/README.html#getting-started">Getting Started</a></li>
<li><a href="tutorial/README.html#openapi">OpenAPI</a></li>
<li><a href="tutorial/README.html#in-the-flow">In the Flow</a></li>
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<li><a href="tutorial/README.html#mock-mock">Mock, mock!</a></li>
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