Interview Q&A

Short answer: import axios from 'axios'; jest.mock('axios'); axios.get.mockResolvedValue({ data: 'mock data' });

Example code

import axios from 'axios'; jest.mock('axios'); axios.get.mockResolvedValue({ data: 'mock data' });

Real-world example (ShopNest)

ShopNest’s storefront is React: components for ProductCard, CartDrawer, and CheckoutForm, with hooks for local UI state.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: on the server. This allows search engines to crawl the content.

Real-world example (ShopNest)

ShopNest’s storefront is React: components for ProductCard, CartDrawer, and CheckoutForm, with hooks for local UI state.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: dependencies can lead to bugs or infinite loops.

Real-world example (ShopNest)

ShopNest’s cart icon uses useState for count and useEffect to load the cart once on mount.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: styled based on props or state.

Real-world example (ShopNest)

ShopNest’s storefront is React: components for ProductCard, CartDrawer, and CheckoutForm, with hooks for local UI state.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: You can import regular CSS files directly into your components. import './App.css'; // Regular CSS file

Real-world example (ShopNest)

ShopNest’s storefront is React: components for ProductCard, CartDrawer, and CheckoutForm, with hooks for local UI state.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: assets. It’s highly configurable and can be used for React apps, though tools like CRA automate this.

Real-world example (ShopNest)

ShopNest’s storefront is React: components for ProductCard, CartDrawer, and CheckoutForm, with hooks for local UI state.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: express-validator Joi yup zod All support schema-based and custom validations.

Real-world example (ShopNest)

Express middleware authenticates JWT, then the /orders route handler creates the order.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Uses semantic versioning: MAJOR.MINOR.PATCH. New major versions can include breaking changes.

Real-world example (ShopNest)

A ShopNest BFF in Node.js aggregates catalog and price APIs for the React storefront.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: ll support schema-based and custom validations.

Real-world example (ShopNest)

Express middleware authenticates JWT, then the /orders route handler creates the order.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Typical options include: JWT tokens OAuth API keys Sessions (less common for APIs) 📌 Usually, the client includes a token in the Authorization header: Authorization: Bearer <token> The server verifies the token on every request.

Real-world example (ShopNest)

A ShopNest BFF in Node.js aggregates catalog and price APIs for the React storefront.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: uthorization: Bearer <token> The server verifies the token on every request.

Real-world example (ShopNest)

A ShopNest BFF in Node.js aggregates catalog and price APIs for the React storefront.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: JWT (JSON Web Token) is a compact, URL-safe token used for securely transmitting information. Consists of Header, Payload, and Signature Used to verify user identity and permissions 📌 Generate: const jwt = require('jsonwebtoken'); const token = jwt.sign({ id: user.id }, 'secret', { expiresIn: '1h' }); 📌 Verify: jwt.verify(token, 'secret');

Real-world example (ShopNest)

A ShopNest BFF in Node.js aggregates catalog and price APIs for the React storefront.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Use the multer middleware: npm install multer 📌 Example: const multer = require('multer'); const upload = multer({ dest: 'uploads/' }); app.post('/upload', upload.single('file'), (req, res) => { res.send('File uploaded'); });

Example code

Use the multer middleware: npm install multer 📌 Example: const multer = require('multer');
const upload = multer({ dest: 'uploads/' }); app.post('/upload', upload.single('file'), (req, res) => { res.send('File uploaded'); });

Real-world example (ShopNest)

A ShopNest BFF in Node.js aggregates catalog and price APIs for the React storefront.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: pp.post('/upload', upload.single('file'), (req, res) => { res.send('File uploaded'); }); pp.post('/upload', upload.single('file'), (req, res) => { res.send('File uploaded'); }); pp.post('/upload', upload.single('file'), (req, res) => { res.send('File uploaded'); }); pp.post('/upload', upload.single('file'), (req, res) => { res.send('File uploaded'); });

Real-world example (ShopNest)

A ShopNest BFF in Node.js aggregates catalog and price APIs for the React storefront.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Use testing frameworks: Jest or Mocha for unit tests Supertest for HTTP API testing 📌 Example with Supertest: const request = require('supertest'); request(app) .get('/api/users') .expect(200) .then(res => { console.log(res.body); });

Real-world example (ShopNest)

A ShopNest BFF in Node.js aggregates catalog and price APIs for the React storefront.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Use the morgan middleware: npm install morgan const morgan = require('morgan'); app.use(morgan('dev')); Logs every request with method, status, time, etc.

Example code

Use the morgan middleware: npm install morgan const morgan = require('morgan'); app.use(morgan('dev')); Logs every request with method, status, time, etc.

Real-world example (ShopNest)

A ShopNest BFF in Node.js aggregates catalog and price APIs for the React storefront.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: pp.use(morgan('dev')); Logs every request with method, status, time, etc. pp.use(morgan('dev')); Logs every request with method, status, time, etc. pp.use(morgan('dev')); Logs every request with method, status, time, etc. pp.use(morgan('dev')); Logs every request with method, status, time, etc.

Real-world example (ShopNest)

A ShopNest BFF in Node.js aggregates catalog and price APIs for the React storefront.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Use plural nouns in endpoints (/users, not /user) Use proper HTTP methods Send meaningful status codes Keep URLs simple and consistent Use pagination for large data Protect with authentication/authorization Use versioning (/api/v1/...) Validate and sanitize all inputs NPM and module-related Node.js interview questions

Real-world example (ShopNest)

A ShopNest BFF in Node.js aggregates catalog and price APIs for the React storefront.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Negotiate before you resign, not after. Your leverage is a clean handover plan plus a new employer willing to wait—or partially buy out the notice. Most Indian IT firms (TCS, Infosys, Wipro) will consider 60→45 or 90→60 days when the project risk is low and your manager sponsors the request.

Why this matters in Notice Period

A 90-day clause is common for senior roles and service companies. HR cannot usually change policy alone; your reporting manager’s sign-off matters more than an emotional appeal.

Step-by-step approach

1. Read your appointment letter: notice period, garden leave, PTO adjustment, and buyout clause.
2. Get your new offer letter with a realistic joining date (add 2-week buffer beyond expected release).
3. Draft a 1-page transition plan: open tickets, KT owners, release calendar, and critical client calls.
4. Meet your manager privately first—ask what minimum handover they need, not “please waive everything.”
5. Email HR with manager CC: requested last working day, transition summary, and willingness for partial buyout if needed.
6. Confirm release date in writing before telling the new company your final join date.

Real-world example

Rahul, a 5 YOE .NET developer at Infosys, received a Flipkart offer needing join in 55 days while his notice was 90. He listed 3 modules he owned, proposed 4 KT sessions, and offered to finish a sprint-critical API before exit. His manager agreed to sponsor 60-day release; HR approved because the account lead signed off. Rahul paid no buyout and joined on time.

What to say / email template

Subject: Request for notice period discussion — Rahul Sharma (Emp ID: 12345)

Dear [Manager Name],

Thank you for the opportunities on [Project/Account]. I have accepted an offer elsewhere and will submit formal resignation shortly. My contractual notice is 90 days; the new employer has requested joining by [date].

I prepared a transition plan (attached) covering KT, open defects, and release ownership. I am requesting support for an early release of [X days / target LWD: DD-MMM-YYYY], subject to HR policy.

I am committed to a professional handover and will remain fully available until my last working day.

Regards,
Rahul

Numbers & benchmarks

• Service companies: 90 days common for 3–8 YOE; product startups often expect 30–45 days.
• Realistic reduction: 90→60 or 90→45 days when KT is documented—not 90→15 without buyout.
• Buyout cost (if allowed): often 1–3 months basic salary—negotiate with new employer as joining bonus.

Mistakes to avoid

• Resigning first, then begging for reduction—always align with manager before HR.
• Bad-mouthing the company or threatening to leave immediately.
• Promising a join date to the new employer before written release approval.
• Skipping KT documentation—managers reject early release when bus factor is you.

The sentence that works: “I want to protect the account and leave on good terms—here is how I will hand over in X weeks.”

Short answer: Reduction means proving the business can run without you in fewer days. Combine manager sponsorship, documented KT, and optionally using accumulated leave or buyout. Target a specific last working day (LWD), not a vague “as soon as possible.”

Step-by-step approach

1. Calculate calendar days: 90 working days ≠ 90 calendar days—check if weekends/holidays count in your policy.
2. Identify low-risk period: post-release, between projects, or after major go-live.
3. Offer concrete KT: recordings, runbooks, shadow sessions, and access revocation checklist.
4. Ask HR about leave adjustment (paid leave during notice) vs buyout—policies differ by company.
5. Escalate politely if HR stalls: ask for policy reference and approval workflow in writing.
6. Keep performing normally—performance drops are a common reason managers block early release.

Real-world example

Ananya, QA lead at TCS with 90-day notice, wanted to join a Bangalore product startup in 70 days. She created Confluence pages for 40 test cases, paired a junior QA for 2 weeks, and proposed LWD after the UAT sign-off. Account manager agreed; HR reduced notice to 75 days and allowed 5 days of earned leave in the notice window.

Numbers & benchmarks

• Typical achievable reduction with good KT: 15–30 days off a 90-day notice.
• Leave during notice: many firms cap how many PTO days offset the notice period.

Mistakes to avoid

• Assuming all companies treat notice the same—MNC captives vs Indian service vs product differ widely.
• Going straight to HR bypassing your manager (manager can block silently).
• Using sick leave patterns to cut notice—can trigger compliance review.
• Sharing confidential client data in KT docs stored on personal drives.

If reduction is denied, ask: “What specific handover milestones would make a 60-day release acceptable?”

Short answer: Early release is a business decision, not a favor. You need manager + HR + sometimes client approval. Make it easy to say yes: low transition risk, no open escalations, and a replacement or clear backlog plan.

Step-by-step approach

1. Check if your project is in a critical phase—avoid requesting release during go-live week.
2. Identify who must approve: manager, HRBP, delivery head, sometimes client POC.
3. Submit resignation with professional tone; attach transition timeline.
4. Volunteer for overlap with your replacement or extended support calls (within policy).
5. If denied, ask for interim date review after milestone X is delivered.
6. Document all approvals—Relieving letter and experience letter dates must match LWD.

Real-world example

Vikram, DevOps engineer at Wipro, was on a 90-day notice. His pipeline work was automated; on-call was shared. He trained two teammates on Terraform modules and showed 30 days of clean incident history. Delivery manager approved 45-day release; client had no objection because KT was recorded.

What to say / email template

Talking point to manager:
"Our release is stable and documented. I propose LWD [date] after these 3 KT sessions. I can stay reachable on email for 2 weeks post-exit for critical questions if policy allows."

Mistakes to avoid

• Disengaging after resignation (“quiet quitting”)—guarantees denial.
• Demanding early release citing only personal reasons without handover plan.
• Accepting verbal OK without HR portal/email confirmation.
• Starting full-time work at the new company while still on old payroll—legal and tax risk.

Offer a 30-minute weekly KT call during part of your notice if the team is short-staffed—often unlocks flexibility.

Short answer: Sometimes yes—if your employment contract or HR policy allows notice buyout. You (or your new employer) pay compensation for unserved notice days, usually basic salary equivalent. Not all companies permit it; captives and banks often do not.

Step-by-step approach

1. Search offer letter for “notice buyout,” “payment in lieu of notice,” or “shortfall recovery.”
2. Ask HR explicitly: “Is buyout allowed for my band and account?”
3. Get the formula: basic only vs CTC vs fixed components—amounts vary hugely.
4. Negotiate with new employer: joining bonus or relocation can cover buyout cost.
5. Pay only after written approval and final settlement calculation from HR.
6. Keep receipts and F&F settlement sheet for tax and future employment verification.

Real-world example

Priya’s product company required 30-day join; her MNC had 60-day notice with buyout at 1 month basic (₹85,000). Flipkart added ₹1L joining bonus conditioned on start date. Priya paid buyout, joined on time, and claimed reimbursement per offer letter clause.

Numbers & benchmarks

• Buyout range: 0.5–3 months of basic/common salary depending on employer.
• Some firms allow new employer to pay directly to old HR—ask both sides.
• Recovery on absconding is often higher than voluntary buyout—never compare them equally.

Mistakes to avoid

• Assuming buyout is automatic—it is often discretionary.
• Paying buyout without formal HR letter (scams/fake HR requests—verify domain).
• Not clarifying if variable pay / bonus is forfeited on early exit.
• Skipping tax treatment discussion on buyout and F&F components.

Phrase to new employer: “My notice buyout is approximately ₹X—can we align joining bonus or one-time payment to offset this?”

Short answer: A 90-day notice is not bad for your career—it is common in Indian IT services. What hurts growth is unplanned exits, burning bridges, or long gaps while serving notice without upskilling. Product companies know service-sector notice norms.

Why this matters in Notice Period

Recruiters ask about notice on the first call. Transparency + early release plan beats hiding your situation.

Step-by-step approach

1. Disclose notice length early in interviews—surprises at offer stage kill deals.
2. Use notice period to finish certifications, portfolio updates, and system design prep.
3. Avoid negative posts about long notice on LinkedIn—frame as “standard for my current employer.”
4. Track release approvals weekly so offers do not expire.
5. If stuck 90 days, negotiate partial remote or learning time with manager.
6. Build relationships during notice—references matter for senior roles.

Real-world example

Ananya served full 90 days at Cognizant but used evenings for Azure certification and mock interviews. She joined Zoho with a clear story: “I honored commitment, automated handover, and upskilled.” Interviewers valued reliability over speed.

Mistakes to avoid

• Believing only 15-day notice companies are “good”—many strong firms accept 90 with planning.
• Going idle during notice—recruiters notice skill rust in later rounds.
• Accepting counter-offers without fixing why you wanted to leave.
• Letting frustration show in team meetings during long notice.

Follow-up questions you may get

• “Can you join in 30 days?” — Explain actual notice + KT plan + possible buyout.
• “Why is your notice so long?” — Industry norm for service co; not a performance issue.

Growth comes from skills and outcomes, not notice length alone—use the window deliberately.

Short answer: If your contract specifies notice and you resign voluntarily, the employer can require you to serve it or pay buyout if allowed. They generally cannot force unpaid labor beyond contract, but absconding triggers recovery clauses and legal risk.

Why this matters in Notice Period

Indian employment law is contract-driven. IT industry norms are strong but not above written terms.

Step-by-step approach

1. Re-read appointment letter, bond (if any), and separation policy.
2. Understand consequences of not serving: salary hold, experience letter delay, negative verification.
3. If employer denies release without cause, escalate to HRBP with documented KT proof.
4. Consult labor lawyer only for clear violations (harassment, withheld salary illegally)—rare for standard notice disputes.
5. Never stop working without formal acceptance of absconding consequences.
6. Negotiate buyout or partial serve if full 90 days is impossible for new offer.

Real-world example

A developer’s manager refused early release despite empty backlog. HR cited policy: full 60 days or buyout. He chose buyout funded by new employer rather than absconding—avoided blacklist on background verification vendors used by top product firms.

Numbers & benchmarks

• Background verification failures on notice absconding can delay offers 2–8 weeks.
• Recovery claims: typically basic salary for unserved days plus statutory adjustments.

Mistakes to avoid

• Assuming “I can leave anytime” in at-will myths—India is not US at-will for most IT contracts.
• Absconding to join startup—many vendors flag “did not serve notice.”
• Threatening legal action without grounds—burns references.
• Ignoring garden leave instructions while working elsewhere.

If stuck, serve professionally—your reputation outlasts one long notice.

Short answer: Leaving without notice (absconding) usually triggers salary forfeiture, negative or delayed experience letter, recovery notices, and failed background checks. Some employers mark “not eligible for rehire.” New employers may revoke offers if verification fails.

Step-by-step approach

1. Calculate total cost: recovery letter + legal fees + offer loss vs buyout cost.
2. Contact old HR to negotiate settlement—even after leaving—some accept buyout late.
3. Document any harassment or illegal withholding if that forced exit (seek legal advice).
4. Prepare honest explanation for future employers—avoid lying on verification forms.
5. Complete PF/gratuity transfer separately—absconding complicates but does not always block PF.
6. Rebuild trust with strong references from other managers/clients if possible.

Real-world example

Karthik absconded from a service firm after 20 days of 90-day notice to join a startup. BGV failed; startup withdrew offer. He paid settlement after 6 months, got experience letter, and re-applied—lost a year of seniority progression. Buyout would have cost less than career damage.

Mistakes to avoid

• Believing small companies “do not check” notice history—they use third-party BGV.
• Ignoring recovery emails—accumulates interest and legal escalation in some cases.
• Using fake experience letters—criminal fraud risk.
• Assuming new employer will always protect you—they protect their hiring compliance first.

Follow-up questions you may get

• “Why did you leave abruptly?” — Own mistake, explain settlement, emphasize reliability since then.

Almost always cheaper and safer to negotiate buyout or serve partial notice than to abscond.