sentry-tanstack-start-sdk

All Skills > SDK Setup > TanStack Start React SDK

Sentry TanStack Start React SDK

Opinionated wizard that scans your TanStack Start React project and guides you through complete Sentry setup for browser and server runtimes.

Invoke This Skill When

• User asks to "add Sentry to TanStack Start" or "set up Sentry" in a TanStack Start React app
• User wants to install or configure @sentry/tanstackstart-react
• User wants error monitoring, tracing, session replay, logs, or user feedback for TanStack Start React
• User asks about sentryTanstackStart, wrapFetchWithSentry, instrument.server.mjs, or TanStack Start middleware instrumentation

Note: This SDK is currently alpha and documented as compatible with TanStack Start 1.0 RC. Always verify against docs.sentry.io/platforms/javascript/guides/tanstackstart-react/ before implementing.

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Phase 1: Detect

Run these commands to understand the project before making any recommendations:

# Detect TanStack Start / Router and existing Sentry
cat package.json | grep -E '"@tanstack/react-start"|"@tanstack/react-router"|"@sentry/tanstackstart-react"'

# Check if Sentry is already present
cat package.json | grep '"@sentry/'

# Detect key files used by the TanStack Start setup
ls src/router.tsx src/start.ts src/server.ts instrument.server.mjs vite.config.ts vite.config.js 2>/dev/null

# Check whether source map upload credentials are configured
cat .env .env.local .env.sentry-build-plugin 2>/dev/null | grep "SENTRY_AUTH_TOKEN"

# Detect deployment hints in scripts
cat package.json | grep -E '"dev"|"build"|"start"|NODE_OPTIONS|--import'

# Detect logging libraries
cat package.json | grep -E '"pino"|"winston"|"loglevel"'

# Detect companion backend directories
ls ../backend ../server ../api 2>/dev/null
cat ../go.mod ../requirements.txt ../Gemfile ../pom.xml 2>/dev/null | head -3

What to determine:

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Phase 2: Recommend

Present a concrete recommendation based on what you found. Do not ask open-ended questions — lead with a proposal:

Recommended (core coverage):

• ✅ Error Monitoring — always; captures unhandled client and server errors
• ✅ Tracing — high-value for request and route timing across browser and server
• ✅ Session Replay — recommended for user-facing apps

Optional (enhanced observability):

• ⚡ Logs — recommend when structured log search and log-to-trace correlation are needed
• ⚡ User Feedback — recommend when product teams want in-app issue reports

Recommendation logic:

Propose: "I recommend Error Monitoring + Tracing + Session Replay. Want me to also enable Logs and User Feedback?"

---

Phase 3: Guide

Install

npm install @sentry/tanstackstart-react --save

Configure Client-Side Sentry in src/router.tsx

Initialize Sentry inside the router factory and gate it to the browser:

import * as Sentry from "@sentry/tanstackstart-react";
import { createRouter } from "@tanstack/react-router";

export const getRouter = () => {
  const router = createRouter();

  if (!router.isServer) {
    Sentry.init({
      dsn: "___PUBLIC_DSN___",
      sendDefaultPii: true,

      integrations: [
        Sentry.tanstackRouterBrowserTracingIntegration(router),
        Sentry.replayIntegration(),
        Sentry.feedbackIntegration({
          colorScheme: "system",
        }),
      ],

      enableLogs: true,
      tracesSampleRate: 1.0,
      replaysSessionSampleRate: 0.1,
      replaysOnErrorSampleRate: 1.0,
    });
  }

  return router;
};

Configure Server-Side Sentry in instrument.server.mjs

Create instrument.server.mjs in project root:

import * as Sentry from "@sentry/tanstackstart-react";

Sentry.init({
  dsn: "___PUBLIC_DSN___",
  sendDefaultPii: true,
  enableLogs: true,
  tracesSampleRate: 1.0,
});

Configure Vite Plugin in vite.config.ts

sentryTanstackStart should be the last plugin:

import { defineConfig } from "vite";
import { sentryTanstackStart } from "@sentry/tanstackstart-react/vite";
import { tanstackStart } from "@tanstack/react-start/plugin/vite";

export default defineConfig({
  plugins: [
    tanstackStart(),
    sentryTanstackStart({
      org: "___ORG_SLUG___",
      project: "___PROJECT_SLUG___",
      authToken: process.env.SENTRY_AUTH_TOKEN,
    }),
  ],
});

If the token is stored in .env, load it with loadEnv in the Vite config before passing it to the plugin.

Instrument Server Entry Point in src/server.ts

Wrap the fetch handler with wrapFetchWithSentry:

import { wrapFetchWithSentry } from "@sentry/tanstackstart-react";
import handler, { createServerEntry } from "@tanstack/react-start/server-entry";

export default createServerEntry(
  wrapFetchWithSentry({
    fetch(request: Request) {
      return handler.fetch(request);
    },
  }),
);

Add Global Server Middleware in src/start.ts

These middleware capture server-side request and function errors:

import {
  sentryGlobalFunctionMiddleware,
  sentryGlobalRequestMiddleware,
} from "@sentry/tanstackstart-react";
import { createStart } from "@tanstack/react-start";

export const startInstance = createStart(() => {
  return {
    requestMiddleware: [sentryGlobalRequestMiddleware],
    functionMiddleware: [sentryGlobalFunctionMiddleware],
  };
});

Sentry middleware should be first in each array.

Runtime Startup Patterns

Choose one runtime method:

--import examples:

{
  "scripts": {
    "dev": "NODE_OPTIONS='--import ./instrument.server.mjs' vite dev --port 3000",
    "build": "vite build && cp instrument.server.mjs .output/server",
    "start": "node --import ./.output/server/instrument.server.mjs .output/server/index.mjs"
  }
}

Direct import fallback (top of src/server.ts):

import "../instrument.server.mjs";

For Each Agreed Feature

Walk through features one at a time. Load the reference file, follow steps exactly, and verify before moving on:

For each feature: Read ${SKILL_ROOT}/references/<feature>.md, follow steps exactly, verify it works.

---

Configuration Reference

Key Sentry.init() Options

TanStack Start-Specific APIs

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Verification

Trigger test events to confirm Sentry receives data.

Issues Test (Frontend)

<button
  type="button"
  onClick={() => {
    throw new Error("Sentry Test Error");
  }}
>
  Break the world
</button>

Tracing Test (Frontend + API Route)

<button
  type="button"
  onClick={async () => {
    await Sentry.startSpan({ name: "Example Frontend Span", op: "test" }, async () => {
      const res = await fetch("/api/sentry-example");
      if (!res.ok) {
        throw new Error("Sentry Example Frontend Error");
      }
    });
  }}
>
  Break the world
</button>

Logs Test

Sentry.logger.info("User example action completed");
Sentry.logger.warn("Slow operation detected", { operation: "data_fetch", duration: 3500 });
Sentry.logger.error("Validation failed", { field: "email", reason: "Invalid email" });

Confirm in Sentry:

• Issues: frontend/server errors appear
• Traces: browser and server spans appear
• Replays: session replay appears when enabled
• Logs: log lines appear when enableLogs: true
• User Feedback: submissions appear when feedback integration is enabled

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Phase 4: Cross-Link

After completing TanStack Start setup, check whether a companion backend exists without Sentry:

ls ../backend ../server ../api ../go ../python 2>/dev/null
cat ../go.mod ../requirements.txt ../pyproject.toml ../Gemfile ../pom.xml 2>/dev/null | head -5

If a backend exists without Sentry configured, suggest the matching skill:

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Troubleshooting