<div class="chartlet-wrapper"><style>.chartlet-stage{position:relative;display:inline-block;max-width:100%;vertical-align:top}.chartlet-stage>svg{display:block}.chartlet-hotspot{position:absolute;border-radius:8px;cursor:pointer}.chartlet-focus{margin:0 0 12px 0;font-size:13px}.chartlet-focus summary{cursor:pointer;min-height:24px}.chartlet-focus fieldset{border:none;padding:0;margin:4px 0 0 0}.chartlet-focus label{display:inline-flex;align-items:center;min-height:44px;margin-right:14px;cursor:pointer;white-space:nowrap}.chartlet-focus input{margin-right:4px}.chartlet-focus input:focus-visible{outline:2px solid #2563eb;outline-offset:2px}.chartlet-wrapper:has(.chartlet-focus-node:checked) #chartlet-00195d7e9e740778 .chartlet-f{opacity:.18}#chartlet-00195d7e9e740778-hs-0{left:43.6%;top:3.077%;width:12.8%;height:9.231%}#chartlet-00195d7e9e740778-hs-1{left:44%;top:28.462%;width:12%;height:12.308%}#chartlet-00195d7e9e740778-hs-2{left:44.8%;top:56.923%;width:10.4%;height:10.769%}#chartlet-00195d7e9e740778-hs-3{left:44.8%;top:83.846%;width:10.4%;height:12.308%}.chartlet-wrapper:has(#chartlet-00195d7e9e740778-focus-0:checked) #chartlet-00195d7e9e740778 .chartlet-f-0{opacity:1}.chartlet-wrapper:has(#chartlet-00195d7e9e740778-focus-0:checked) #chartlet-00195d7e9e740778 .chartlet-n-0 .chartlet-flow-node,.chartlet-wrapper:has(#chartlet-00195d7e9e740778-focus-0:checked) #chartlet-00195d7e9e740778 .chartlet-n-0 .chartlet-seq-box{stroke-width:3}.chartlet-wrapper:has(#chartlet-00195d7e9e740778-focus-1:checked) #chartlet-00195d7e9e740778 .chartlet-f-1{opacity:1}.chartlet-wrapper:has(#chartlet-00195d7e9e740778-focus-1:checked) #chartlet-00195d7e9e740778 .chartlet-n-1 .chartlet-flow-node,.chartlet-wrapper:has(#chartlet-00195d7e9e740778-focus-1:checked) #chartlet-00195d7e9e740778 .chartlet-n-1 .chartlet-seq-box{stroke-width:3}.chartlet-wrapper:has(#chartlet-00195d7e9e740778-focus-2:checked) #chartlet-00195d7e9e740778 .chartlet-f-2{opacity:1}.chartlet-wrapper:has(#chartlet-00195d7e9e740778-focus-2:checked) #chartlet-00195d7e9e740778 .chartlet-n-2 .chartlet-flow-node,.chartlet-wrapper:has(#chartlet-00195d7e9e740778-focus-2:checked) #chartlet-00195d7e9e740778 .chartlet-n-2 .chartlet-seq-box{stroke-width:3}.chartlet-wrapper:has(#chartlet-00195d7e9e740778-focus-3:checked) #chartlet-00195d7e9e740778 .chartlet-f-3{opacity:1}.chartlet-wrapper:has(#chartlet-00195d7e9e740778-focus-3:checked) #chartlet-00195d7e9e740778 .chartlet-n-3 .chartlet-flow-node,.chartlet-wrapper:has(#chartlet-00195d7e9e740778-focus-3:checked) #chartlet-00195d7e9e740778 .chartlet-n-3 .chartlet-seq-box{stroke-width:3}</style><details class="chartlet-focus"><summary>Focus</summary><fieldset><label><input type="radio" name="chartlet-00195d7e9e740778-focus" checked> Show all</label><label><input type="radio" name="chartlet-00195d7e9e740778-focus" class="chartlet-focus-node" id="chartlet-00195d7e9e740778-focus-0"> Shop front end</label><label><input type="radio" name="chartlet-00195d7e9e740778-focus" class="chartlet-focus-node" id="chartlet-00195d7e9e740778-focus-1"> Load balancer</label><label><input type="radio" name="chartlet-00195d7e9e740778-focus" class="chartlet-focus-node" id="chartlet-00195d7e9e740778-focus-2"> Orders API</label><label><input type="radio" name="chartlet-00195d7e9e740778-focus" class="chartlet-focus-node" id="chartlet-00195d7e9e740778-focus-3"> Orders</label></fieldset></details><figure class="chartlet-figure" data-viz="chart"><figcaption>Orders API: components</figcaption><div class="chartlet-stage"><svg xmlns="http://www.w3.org/2000/svg" width="1000" height="520" viewBox="0 0 1000 520" id="chartlet-00195d7e9e740778" role="img" aria-labelledby="chartlet-00195d7e9e740778-title chartlet-00195d7e9e740778-description" class="chartlet-root"><title id="chartlet-00195d7e9e740778-title">Orders API: components</title><desc id="chartlet-00195d7e9e740778-description">Architecture diagram with 4 components and 3 connections. Shop front end (frontend): connects to Load balancer (places orders, via HTTPS). Load balancer (service, load balancer): connects to Orders API (routes, via HTTP). Orders API (service): connects to Orders (reads, writes, via SQL). Orders (database): no outgoing connection.</desc><style>.chartlet-root{--chartlet-text:#172033;--chartlet-muted:#344054;--chartlet-grid:#d9dee8;--chartlet-zero:#667085;--chartlet-accent:#2563eb;--chartlet-background:#fff;--chartlet-color-1:#2563eb;--chartlet-color-2:#c2410c;--chartlet-color-3:#475569;--chartlet-color-4:#111827;max-width:100%;height:auto;font-family:Inter,ui-sans-serif,system-ui,sans-serif;color:var(--chartlet-text)}#chartlet-00195d7e9e740778 .chartlet-title{font-size:22px;font-weight:650;fill:var(--chartlet-text)}#chartlet-00195d7e9e740778 .chartlet-label,#chartlet-00195d7e9e740778 .chartlet-tick,#chartlet-00195d7e9e740778 .chartlet-value,#chartlet-00195d7e9e740778 .chartlet-value-inverse,#chartlet-00195d7e9e740778 .chartlet-axis-title{font-size:12px;fill:var(--chartlet-muted)}#chartlet-00195d7e9e740778 .chartlet-value,#chartlet-00195d7e9e740778 .chartlet-value-inverse{font-weight:600}#chartlet-00195d7e9e740778 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class="chartlet-f chartlet-n-0 chartlet-f-0 chartlet-f-1"></g><g class="chartlet-f chartlet-n-1 chartlet-f-0 chartlet-f-1 chartlet-f-2"></g><g class="chartlet-f chartlet-n-2 chartlet-f-1 chartlet-f-2 chartlet-f-3"></g><g class="chartlet-f chartlet-n-3 chartlet-f-2 chartlet-f-3"></g><g class="chartlet-f chartlet-f-0 chartlet-f-1"><rect x="504" y="69" width="91.36" height="36" class="chartlet-diagram-chip"/><text x="509" y="83" text-anchor="start" class="chartlet-diagram-chip-text">places orders</text><text x="509" y="98" text-anchor="start" class="chartlet-diagram-chip-text">[HTTPS]</text></g><g class="chartlet-f chartlet-f-1 chartlet-f-2"><rect x="504" y="217" width="55.6" height="36" class="chartlet-diagram-chip"/><text x="509" y="231" text-anchor="start" class="chartlet-diagram-chip-text">routes</text><text x="509" y="246" text-anchor="start" class="chartlet-diagram-chip-text">[HTTP]</text></g><g class="chartlet-f chartlet-f-2 chartlet-f-3"><rect x="504" y="357" width="92.32" height="36" class="chartlet-diagram-chip"/><text x="509" y="371" text-anchor="start" class="chartlet-diagram-chip-text">reads, writes</text><text x="509" y="386" text-anchor="start" class="chartlet-diagram-chip-text">[SQL]</text></g><g class="chartlet-f chartlet-n-0 chartlet-f-0 chartlet-f-1"><rect x="436" y="18.5" width="128" height="48" class="chartlet-diagram-shadow"/><rect x="436" y="16" width="128" height="48" class="chartlet-flow-node chartlet-role-blue"><title>Shop front end</title></rect><line x1="436" y1="28" x2="564" y2="28" class="chartlet-flow-inner"/><circle cx="444" cy="22" r="1.8" class="chartlet-arch-dot"/><circle cx="450" cy="22" r="1.8" class="chartlet-arch-dot"/><circle cx="456" cy="22" r="1.8" class="chartlet-arch-dot"/><text x="500" y="50.5" text-anchor="middle" class="chartlet-flow-label">Shop front end</text></g><g class="chartlet-f chartlet-n-1 chartlet-f-0 chartlet-f-1 chartlet-f-2"><rect x="440" y="150.5" width="120" height="64" class="chartlet-diagram-shadow"/><rect x="440" y="148" width="120" height="64" class="chartlet-flow-node chartlet-role-blue"><title>Load balancer</title></rect><use href="#chartlet-00195d7e9e740778-symbol-load-balancer" x="491" y="163.5" width="18" height="18" class="chartlet-arch-symbol"/><text x="500" y="195.5" text-anchor="middle" class="chartlet-flow-label">Load balancer</text></g><g class="chartlet-f chartlet-n-2 chartlet-f-1 chartlet-f-2 chartlet-f-3"><rect x="448" y="298.5" width="104" height="56" class="chartlet-diagram-shadow"/><rect x="448" y="296" width="104" height="56" class="chartlet-flow-node chartlet-role-blue"><title>Orders API – Node.js</title></rect><text x="500" y="321.5" text-anchor="middle" class="chartlet-flow-label">Orders API</text><text x="500" y="335.5" text-anchor="middle" class="chartlet-flow-sublabel">Node.js</text></g><g class="chartlet-f chartlet-n-3 chartlet-f-2 chartlet-f-3"><polyline points="448,443.5 448,497.5 449.772,498.794 454.967,500 463.23,501.036 474,501.83 486.541,502.33 500,502.5 513.459,502.33 526,501.83 536.77,501.036 545.033,500 550.228,498.794 552,497.5 552,443.5 550.228,442.206 545.033,441 536.77,439.964 526,439.17 513.459,438.67 500,438.5 486.541,438.67 474,439.17 463.23,439.964 454.967,441 449.772,442.206 448,443.5 448,443.5" class="chartlet-diagram-shadow"/><polyline points="448,441 448,495 449.772,496.294 454.967,497.5 463.23,498.536 474,499.33 486.541,499.83 500,500 513.459,499.83 526,499.33 536.77,498.536 545.033,497.5 550.228,496.294 552,495 552,441 550.228,439.706 545.033,438.5 536.77,437.464 526,436.67 513.459,436.17 500,436 486.541,436.17 474,436.67 463.23,437.464 454.967,438.5 449.772,439.706 448,441 448,441" class="chartlet-flow-node chartlet-role-teal"><title>Orders – Postgres</title></polyline><polyline points="448,441 449.772,442.294 454.967,443.5 463.23,444.536 474,445.33 486.541,445.83 500,446 513.459,445.83 526,445.33 536.77,444.536 545.033,443.5 550.228,442.294 552,441" class="chartlet-diagram-rim"/><text x="500" y="468.5" text-anchor="middle" class="chartlet-flow-label">Orders</text><text x="500" y="482.5" text-anchor="middle" class="chartlet-flow-sublabel">Postgres</text></g></svg><label class="chartlet-hotspot" id="chartlet-00195d7e9e740778-hs-0" for="chartlet-00195d7e9e740778-focus-0"></label><label class="chartlet-hotspot" id="chartlet-00195d7e9e740778-hs-1" for="chartlet-00195d7e9e740778-focus-1"></label><label class="chartlet-hotspot" id="chartlet-00195d7e9e740778-hs-2" for="chartlet-00195d7e9e740778-focus-2"></label><label class="chartlet-hotspot" id="chartlet-00195d7e9e740778-hs-3" for="chartlet-00195d7e9e740778-focus-3"></label></div><p class="chartlet-source">Source: Operations handbook, orders model</p><details class="chartlet-data" data-viz-text><summary>Show chart data</summary><table><caption>Data for Orders API: components</caption><thead><tr><th scope="col">Component</th><th scope="col">Kind</th><th scope="col">Connects to</th></tr></thead><tbody><tr><th scope="row">Shop front end</th><td>frontend</td><td>Load balancer (places orders, via HTTPS)</td></tr><tr><th scope="row">Load balancer</th><td>service, load balancer</td><td>Orders API (routes, via HTTP)</td></tr><tr><th scope="row">Orders API</th><td>service</td><td>Orders (reads, writes, via SQL)</td></tr><tr><th scope="row">Orders</th><td>database</td><td></td></tr></tbody></table></details></figure></div>