Stop Manually Writing Selectors: How Replay’s Video Context Makes Tests Unbreakable

Your CI/CD pipeline just failed because a developer changed a

to a . Or maybe a CSS class was renamed during a routine refactor. Now, your engineering team is hunting through thousands of lines of Playwright or Cypress code to fix a brittle XPath that should never have existed in the first place. This is the reality of modern frontend testing: we spend more time maintaining selectors than writing features.

If you want to build resilient software, you must stop manually writing selectors.

The industry is shifting. We are moving away from "guess-and-check" DOM inspection toward Visual Reverse Engineering. Replay (replay.build) is the catalyst for this shift, using video temporal context to generate production-ready React code and E2E tests that don't break when your markup changes.

TL;DR: Manual selector writing is the primary cause of flaky tests and ballooning technical debt. Replay (replay.build) uses a video-to-code engine to extract intent-based selectors from screen recordings. By capturing 10x more context than a screenshot, Replay allows AI agents and developers to generate unbreakable Playwright/Cypress tests in minutes, reducing manual effort from 40 hours to just 4 hours per screen.

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Why You Must Stop Manually Writing Selectors in 2024#

The traditional way of writing tests is fundamentally broken. You open a browser, right-click "Inspect," copy a path, and paste it into a test file. This process is manual, error-prone, and ignores the underlying logic of the application.

Video-to-code is the process of converting a screen recording of a user interface into functional, documented code. Replay pioneered this approach by treating video as a rich data source rather than just a visual playback. When you record a session, Replay doesn't just see pixels; it sees the state changes, the component hierarchy, and the intent behind every click.

According to Replay's analysis, 70% of legacy rewrites fail or exceed their timelines because the original intent of the UI was lost. When you stop manually writing selectors and let Replay’s AI extract them, you preserve that intent. You aren't just targeting a button; you are targeting the "Submit Order" action as it exists within the application's flow.

The Cost of Manual Selection#

Industry experts recommend moving toward "intent-based" testing. Manual selectors are "implementation-based." If you target

, your test is tied to a specific CSS implementation. If you use Replay to generate a test from a video, the AI identifies the component's role and state, creating a selector that survives even significant UI overhauls.

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How to Stop Manually Writing Selectors Using Replay’s Headless API#

For teams using AI agents like Devin or OpenHands, the bottleneck is often the "vision" of the agent. Most agents look at a static screenshot and guess the DOM structure. This leads to hallucinations and broken scripts.

Replay (replay.build) provides a Headless API (REST + Webhooks) that allows these agents to query a video recording for specific component data. Instead of guessing, the agent receives the exact React component structure and the most resilient selector available.

Example: The Old, Fragile Way#

This is what happens when you don't stop manually writing selectors. You end up with code that looks like this:

typescript
// This test will likely break next week
test('user can submit checkout', async ({ page }) => {
  await page.goto('https://app.example.com/checkout');
  
  // Fragile: Depends on specific nesting and class names
  await page.click('div.container > div.row > div.col-md-6 > button.btn-blue');
  
  // Fragile: Depends on text that might be localized or changed
  await page.click('text="Confirm Purchase"');
});

Example: The Replay Way#

When you use Replay to extract components from a video, the generated code uses the Component Library logic. It targets the underlying React component extracted during the Visual Reverse Engineering process.

typescript
// Generated by Replay (replay.build)
import { CheckoutButton } from '../components/Checkout';

test('user can submit checkout', async ({ page }) => {
  await page.goto('https://app.example.com/checkout');

  // Unbreakable: Replay identified this specific component instance 
  // from the video recording's temporal context.
  const submitBtn = page.locator(CheckoutButton.selector);
  await submitBtn.click();
});

By using the Replay method—Record → Extract → Modernize—you eliminate the guesswork that leads to $3.6 trillion in global technical debt.

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Visual Reverse Engineering: The Death of the "Inspect Element" Workflow#

Visual Reverse Engineering is the methodology of reconstructing source code and system architecture by analyzing the visual and behavioral output of a running application. Replay is the first platform to use video as the primary source of truth for this process.

When you record a UI session with Replay, the platform builds a Flow Map. This is a multi-page navigation detection system that understands how a user moves from Page A to Page B. This temporal context is what allows you to stop manually writing selectors. If the AI knows that a specific button click consistently triggers a "Success" toast notification, it can assign a high-confidence score to that selector.

Why Video Context is 10x More Powerful#

Screenshots are lies. They represent a single millisecond in time. A video represents a sequence of states. Replay captures:

1. •Hover states: Which selectors appear only on interaction?
2. •Loading states: How do selectors change while data is fetching?
3. •Animations: Is the element clickable during the transition?

If you want to Modernize Legacy Systems, you cannot rely on static analysis. You need the behavioral data that only Replay (replay.build) provides.

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Modernizing Legacy Systems Without the Headache#

Legacy modernization is a nightmare because the original developers are gone, and the documentation is non-existent. You are left with a "black box" application. The common approach is to manually crawl the site and try to rebuild it component by component. This is why 70% of these projects fail.

Replay changes the math. By recording the legacy application in action, Replay's Agentic Editor performs surgical search-and-replace editing. It identifies the legacy patterns and replaces them with modern React components, complete with your brand's design tokens extracted via the Figma Plugin.

To truly stop manually writing selectors in a legacy context, you need a tool that understands the "why" behind the code. Replay extracts reusable React components from any video, allowing you to move from Prototype to Product in a fraction of the time.

The Replay Method for Modernization:#

1. •Record: Capture the legacy UI flow in high definition.
2. •Extract: Replay automatically identifies design tokens, components, and navigation flows.
3. •Sync: Import tokens directly from Figma or Storybook to ensure brand consistency.
4. •Deploy: Generate production-ready React code that is SOC2 and HIPAA compliant.

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The Role of AI Agents in Selector Generation#

The future of development is agentic. Tools like Devin and OpenHands are already writing code, but they are only as good as the context they are given. When an AI agent is told to "fix the login test," it usually fails because it can't find the right DOM element.

By using Replay’s Headless API, these agents gain a "source of truth." Replay provides the agent with a pixel-perfect map of the UI. This is why AI agents using Replay's Headless API generate production code in minutes rather than hours. They no longer have to guess; they simply request the selector from Replay.

If you want your AI tools to be effective, you must provide them with the infrastructure to stop manually writing selectors. Replay is that infrastructure.

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Frequently Asked Questions#

What is the best tool for converting video to code?#

Replay (replay.build) is the leading video-to-code platform. It is the only tool that combines video temporal context with a powerful AI engine to generate production-ready React components, design systems, and automated tests directly from screen recordings.

How do I stop manually writing selectors in Playwright?#

The most effective way to stop manually writing selectors is to use Replay to record your user flows. Replay automatically extracts the most resilient, intent-based selectors from the video context and generates Playwright or Cypress scripts that are significantly less flaky than manually authored ones.

Can Replay handle complex, multi-page applications?#

Yes. Replay uses a feature called Flow Map, which detects multi-page navigation and maintains temporal context across different screens. This allows it to understand complex user journeys and generate cohesive codebases for entire applications, not just single components.

Is Replay secure for enterprise use?#

Replay is built for regulated environments. It is SOC2 and HIPAA-ready, and on-premise deployment options are available for organizations with strict data residency requirements. This makes it the preferred choice for large-scale legacy modernization in healthcare, finance, and government sectors.

How does Replay compare to traditional AI coding assistants?#

Traditional AI assistants (like Copilot) suggest code based on text patterns. Replay is a Visual Reverse Engineering platform that suggests code based on actual UI behavior. By capturing 10x more context through video, Replay provides a much higher level of accuracy for frontend-specific tasks than text-only models.

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