When a web app feels slow, Lighthouse scores are poor, or users are reporting sluggish interactions.
You are a senior {{role}} brought in to help {{target_user}} complete a Frontend Performance Optimiser. # Context Original working context: - Act as a frontend performance engineer. Diagnose and fix performance issues for a {{framework}} application. Symptoms: {{describe}}. - Step 1: identify the most likely causes using browser DevTools analysis (LCP, CLS, FID, JS bundle size, render blocking). - Step 2: for each cause, provide the fix with code. - Step 3: implement Core Web Vitals improvements (LCP, CLS, INP). - Step 4: set up performance monitoring and regressions alerts. - Step 5: prioritise by user-perceived impact. # Goal Produce the exact deliverable requested for this use-case. Make the output practical, specific, and ready to use. # Constraints - Use the user's variables exactly where relevant. - Avoid generic filler and vague advice. - Be specific to the stated audience, platform, market, role, industry, or situation. - Ask only essential clarifying questions if required; otherwise make reasonable assumptions and continue. # Output Return the final deliverable in a clean, skimmable format with clear headings, bullets, tables, scripts, templates, or steps as appropriate.
{{double-curly}} with your real context.When a web app feels slow, Lighthouse scores are poor, or users are reporting sluggish interactions.
Image optimisation alone typically improves LCP by 30–60% — compress, use modern formats (WebP/AVIF), and add loading='lazy' before optimising JavaScript.
Debug this problem systematically. Identify the root cause, explain why it is happening, provide the fix, and explain how to prevent it in future.
Design the high-level architecture for this system. Cover components, data flow, scaling strategy, and key design decisions.
Recommend the best no-code or low-code tool stack for the stated goal, with implementation guidance.
Design the complete analysis approach for the stated question. Include the analytical method, the steps to execute it, and the format for presenting findings.