Developer Sajeeb

JS tip most devs still get wrong:

value || 'default'
→ also replaces 0, "" and false 😬

value ?? 'default'
→ replaces ONLY null/undefined ✅

If a "0" ever silently became your fallback, this is why.

Pair it with ?. and 5 lines become 1.

Stop asking AI "is my code good?"

That question gets you a compliment. Not a code review.

Here's the prompt I actually use — copy it:

━━━━━━━━━━━━━━━
"Act as a senior engineer doing a strict pull request review on the code below.

Review it in this exact order:
1. Bugs and logic errors — what breaks in production?
2. Security — injection, auth gaps, exposed keys, unvalidated input
3. Performance — unnecessary re-renders, N+1 queries, blocking calls
4. Readability — naming, structure, dead code
5. Edge cases I clearly didn't handle

For each issue: severity (Critical / High / Low), why it matters, and the corrected code.

Do not compliment the code. Do not rewrite everything. Be direct."
━━━━━━━━━━━━━━━

Why this works:
→ You gave it a ROLE (senior engineer, not helpful assistant)
→ You gave it an ORDER (so it doesn't stop at formatting)
→ You gave it an OUTPUT FORMAT (severity + fix)
→ You BLOCKED the flattery ("do not compliment")

That last line changes the output more than anything else.

Vague prompt → vague answer. Structured prompt → an actual senior reviewer.

I use variations of this daily in Cursor and Claude. Saves me hours a week.

More of what I build → developersajeeb.com

Which AI tool are you coding with — Cursor, Copilot, or Claude? 👇

I'm a developer. AI didn't replace me — it made me roughly 3x faster.

The 6 tools that actually earned a spot in my daily workflow:

🔹 Claude — code review, refactoring, writing docs 🔹 Cursor — pair programming inside the editor 🔹 v0 / Lovart — first-draft UI and visuals 🔹 n8n — connecting apps without writing glue code 🔹 Figma AI — design system cleanup 🔹 Perplexity — technical research with sources

Every one of these is free or under $20/month.

Which one are you not using yet? 👇

"Should I use React or Next.js?" — I get asked this every week.

Simple answer:

React → dashboards, internal tools, apps behind a login. SEO doesn't matter. Next.js → marketing sites, e-commerce, blogs, anything Google needs to find.

If people need to FIND you on search, Next.js. If they log in to use it, React is plenty.

Most agencies overcomplicate this. Don't.