Orderly plugin — develop (SDK patterns)

Write plugin code after scaffolding. Covers architecture, interceptor strategies, hooks usage, and best practices.

When to use

• User has scaffolded a plugin with [orderly-plugin-create](../orderly-plugin-create/SKILL.md) and wants to write the actual plugin code.
• User wants to add or modify interceptors, hooks, lifecycle logic.

Three Core Principles

1. Direct SDK Package Usage

- Plugins can use @orderly.network/hooks, @orderly.network/ui, @orderly.network/utils directly — same as in host apps.

1. Only SDK-Declared Injectable Targets Can Be Intercepted

- UI modifications use interceptor pattern, not traditional slots. - Use the Inspector tool to discover available target paths. - Specify a component path (e.g., Trading.OrderEntry.SubmitSection) to intercept.

1. Docs-First with Orderly docs MCP server

- When writing plugin code, fetch API details from the Orderly docs MCP server first instead of guessing from memory. - Prioritize tools like orderlydocssearch, orderlydocsgethook, orderlydocsgetcomponent, and orderlydocsgettype to confirm signatures and usage. - If examples are needed, use orderlydocsgetcomponentdoc, orderlydocsgetworkflow, or orderlydocsget_recipe.

Plugin Types

Widget Details

• Mechanism: Pass { target, component } where component: (Original, props, api) => ReactNode
• Flexibility: No pre-reserved slots; dynamically inject into any declared-injectable component path

Page Details

• Mechanism: Build as a normal React component using SDK UI & Hooks
• Characteristics: Standalone, no interceptor overhead, full layout control
• SDK styling: Use Tailwind CSS utility classes from Orderly SDK

Layout Details

• Constraint: Trading page only. Built-in grid/split plugins currently target the desktop layout.
• Dual usage:

- Via plugin: OrderlyPluginProvider + registerLayoutSplitPlugin() - Via host props: layoutStrategy={gridStrategy} + getInitialLayout={() => ...} on TradingPage

• Built-in layouts: registerLayoutGridPlugin() from @orderly.network/layout-grid (the strategy types themselves come from @orderly.network/layout-core)

Plugin Structure

A plugin exports a registration function:

export function registerMyPlugin(options = {}) {
  return (SDK: OrderlySDK) => {
    SDK.registerPlugin({
      id: "my-plugin",
      name: "My Plugin",
      version: "1.0.0",
      orderlyVersion: ">=3.0.0",

      interceptors: [
        { target: "...", component: (Original, props, api) => {...} },
      ],

      setup: (api) => { /* idempotent non-UI setup */ },

      onError: (error) => { /* error handling */ },
      onFallback: () => <div>Plugin unavailable</div>,
    });
  };
}

Key: The component function in an interceptor is a plain function (not a React component) — it cannot call Hooks directly. Return a wrapper component instead.

Interceptor Strategies

The interceptor function: component: (Original, props, api) => ReactNode

Strategy 1: Enhance (Add Content)

Render additional UI alongside Original:

{
  target: "Trading.OrderEntry.SubmitSection",
  component: (Original, props, api) => {
    const BalanceWarning = () => {
      const { freeCollateral } = useCollateral();
      return (
        <div className="flex flex-col gap-2">
          {freeCollateral < 100 && (
            <div className="text-red-500 text-sm">Insufficient balance</div>
          )}
          <Original {...props} />
        </div>
      );
    };
    return <BalanceWarning />;
  },
}

Strategy 2: Wrap (Add Container)

Wrap Original with a styled container or provider:

{
  target: "OrderBook.Desktop.Asks",
  component: (Original, props, api) => {
    const CustomWrapper = () => (
      <div className="border border-blue-500 rounded">
        <div className="bg-blue-50 p-2 text-sm">Ask Side</div>
        <Original {...props} />
      </div>
    );
    return <CustomWrapper />;
  },
}

Strategy 3: Replace (Substitute Component)

Ignore Original and render custom component. Use with caution:

{
  target: "Trading.OrderEntry.SubmitSection",
  component: (Original, props, api) => (
    <button
      type="button"
      className="bg-green-500 text-white px-6 py-2 rounded"
      disabled={!props.canTrade || props.isMutating}
      onClick={props.onSubmit}
    >
      {props.buttonLabel}
    </button>
  ),
}

Chaining

Multiple plugins on the same target chain: Interceptor A -> Interceptor B -> Original

Hooks Usage in Interceptors

✅ Correct: Return a wrapper component that uses Hooks

component: (Original, props, api) => {
  const Wrapper = () => {
    const { freeCollateral } = useCollateral();
    return (
      <div>
        <span>Available: {freeCollateral}</span>
        <Original {...props} />
      </div>
    );
  };
  return <Wrapper />;
}

❌ Incorrect: Hooks called directly in component

component: (Original, props, api) => {
  const { freeCollateral } = useCollateral(); // ❌ Breaks Rules of Hooks
  return <div>{freeCollateral}</div>;
}

Event Subscription

OrderlyPluginProvider does not currently consume a cleanup function returned by setup, and it may execute setup again when the resolved plugin list changes. Use setup only for idempotent non-UI work. For event subscriptions, prefer a wrapper component with useEffect cleanup and use TrackerEventName enum members.

import { useEffect } from "react";
import { TrackerEventName } from "@orderly.network/types";

component: (Original, props, api) => {
  const Wrapper = () => {
    useEffect(() => {
      const handleOrderPlaced = (data: unknown) => {
        console.log("Order placed", data);
      };

      api.events.on(TrackerEventName.placeOrderSuccess, handleOrderPlaced);
      return () => {
        api.events.off(TrackerEventName.placeOrderSuccess, handleOrderPlaced);
      };
    }, [api]);

    return <Original {...props} />;
  };

  return <Wrapper />;
}

Props Typing

Approach A: createInterceptor (Recommended)

import { createInterceptor } from "@orderly.network/plugin-core";
import "@orderly.network/ui"; // Loads Deposit.DepositForm props augmentation

interceptors: [
  createInterceptor("Deposit.DepositForm", (Original, props, api) => {
    // props automatically typed
    return <div onClick={props.onOk}>Custom Form</div>;
  }),
]

Approach B: Manual Generic Type

import type { PluginInterceptor, DepositFormProps } from "@orderly.network/ui";

const interceptor: PluginInterceptor<DepositFormProps> = {
  target: "Deposit.DepositForm",
  component: (Original, props, api) => { /* props typed */ },
};

Approach C: Inline Annotation

component: (Original, props: DepositFormProps, api) => { ... }

Error Hooks and Lifecycle Status

onInitialize and onInstall are present in the current TypeScript descriptor for forward compatibility, but OrderlyPluginProvider does not invoke them yet. Do not rely on them for initialization, compatibility checks, or side effects; use setup or host-level checks instead.

onError: (error: Error) => {
  console.error("Plugin error:", error);
},

onFallback: () => <div>Plugin unavailable</div>,

Best Practices

Error Isolation

• Each interceptor wraps in PluginErrorBoundary
• If an interceptor crashes, only that slot shows blank/fallback — not the entire page

Performance

• Interceptors use memoization — no cascade redraws
• Avoid expensive computations in component functions
• Memoize wrapper components if they receive frequently-changing props:

const MyWrapper = React.memo(({ data, Original, props }) => {
  return <Original {...props} />;
});

component: (Original, props, api) => (
  <MyWrapper Original={Original} props={props} data={someData} />
)

Plugin ID format (single rule)

Must match the Marketplace API wherever the plugin id appears (manifest pluginId, registerPlugin({ id }), CLI --id):

Do not treat registerPlugin({ id }) as a separate camelCase-only rule — hyphenated ids are valid if they match the regex above.

Registration Example

export default function registerMyPlugin(options?: { theme?: string }) {
  return (SDK: OrderlySDK, state?: { orderlyVersion?: string }) =>
    SDK.registerPlugin({
      id: "my-plugin",
      name: "My Plugin",
      version: "1.0.0",

      onError: (error: Error) => {
        console.error("Plugin error:", error);
        // Send to error tracking service
      },

      onFallback: () => <div>Plugin unavailable</div>,

      interceptors: [
        /* ... */
      ],
      setup: (api) => {
        /* ... */
      },
    });
}

Note: onInitialize, onInstall, onMount, onUnmount, and onDispose are not currently invoked by plugin-core.

Testing

• Interceptor Props Validation: Use TypeScript strict mode to catch prop mismatches early.
• Error Scenarios: Test error boundaries by intentionally throwing errors in interceptor components.
• Performance: Use browser DevTools Profiler to verify interceptor rendering doesn't trigger unnecessary redraws.

Reference

[reference.md](reference.md) — shared interceptor targets list (keep in sync with CLI constants)