S #2531
Applications open
Full-Time Job
Backend- Senior Technical Lead
Paytm
About the role
Backend - Technical Lead
About Us
Paytm is India’s largest digital payments and financial services platform, leading the mobile QR revolution. We power millions of businesses and individuals, and we’re building scalable, resilient systems to serve half a billion Indians and beyond.
About the Role
- As a Senior Technical Lead, you’ll not just write code — you’ll design scalable architectures, coach engineers, and lead technology-first projects.
- You'll drive backend systems that support 100M+ DAUs, optimize APIs to sub-50ms latencies, and be a champion of engineering excellence.
- We expect you to actively use AI tools to accelerate architecture design, code reviews, prototyping, and developer productivity.
What We're Looking For
- 6 to 9 years of hands-on backend engineering experience — Java/Nodejs.
- Proven ownership of high-scale distributed systems. Deep knowledge of microservices, messaging systems, caching, storage optimization, and cloud scalability.
- Clear architectural thinking; you can design systems for billions of transactions, not just millions.
- An AI-first mindset — you should know how to augment yourself with GPT and other AI coding tools to move 2x faster.
- Strong leadership skills — mentoring, code reviewing, pushing for engineering best practices.
Why You Should Join Us
- Massive ownership and real-world system building opportunities.
- Work with AI, not against it — code smarter, architect smarter, and build smarter.
- We are a pure tech-driven team inside Paytm — no unnecessary meetings, no bureaucracy.
- You’ll work on critical platforms, live user-impacting systems, and future-proof engineering.
Preferred Qualifications : Bachelor's/Master's Degree in Computer Science or equivalent
Eligibility & process
Who can apply
1) 6 to 9 years of hands-on backend engineering experience — Java/Nodejs. 2) Proven ownership of high-scale distributed systems. Deep knowledge of microservices, messaging systems, caching, storage optimization, and cloud scalability. 3) Clear architectural thinking; you can design systems for billions of transactions, not just millions. 4) An AI-first mindset — you should know how to augment yourself with GPT and other AI coding tools to move 2x faster. 5) Strong leadership skills — mentoring, code reviewing, pushing for engineering best practices.
Skills & stack
Selection process
- As described in the employer's job posting.
Prep kit
20 resourcesStudy material 4
Aptitude Practice Questions & Mock Tests
Curated logical, quantitative, and verbal reasoning problems for the initial online screening round.
Company-Specific Interview Preparation Corner
Detailed interview experiences, exam formats, and previous test questions for Paytm and tech roles.
Technical Placement Question Bank
High-yield coding cheat sheets, core CS fundamentals (OOP, DBMS, OS, Networks), and rapid revision guides.
Algorithm, DSA & Live Code Debugger Practice
Hands-on problem sets to improve coding speed and step-by-step memory debugging.
Company-specific guides 4
APTITUDE & LOGIC
Aptitude Practice Questions & Online Mock Tests
Curated logical, quantitative, and verbal reasoning problems to sharpen reasoning skills required for the initial screening test.
COMPANY GUIDE
Paytm Interview Preparation Corner
Comprehensive guide covering typical interview formats, common questions, and preparation tips for Paytm and off-campus tech roles.
MOCK TESTS & PAPERS
Comprehensive Interview Prep Resources & Syllabus
Collection of previous year questions, company-specific test patterns, and interview experiences for technical and HR rounds.
CODING PRACTICE
Algorithm and Data Structure Problem Set
Practice problems to improve coding proficiency and algorithm problem-solving speed for technical rounds.
Likely coding questions 4
Round-wise strategy 4
Round 1: Online Assessment (OA)
Aptitude, Quantitative Logic & 2 Coding Problems
Focus on accuracy and speed. Practice arrays, strings, and standard arithmetic puzzles.
Round 2: Technical Interview 1
Core Tech Stack (Java, Node.js, Microservices, Distributed Systems) & Live Code Tracing
Explain your thought process aloud. Analyze time & space complexities before coding.
Round 3: System Design & Problem Solving
Database Schemas, APIs & Architecture Basics
Clarify edge cases, diagram schemas cleanly, and discuss scalability trade-offs.
Round 4: HR & Cultural Fit Discussion
Paytm Core Values, Learning Agility & Offer Terms
Demonstrate passion, strong communication, and readiness for full-time collaboration.
Technical questions 5
Explain OOP (Object-Oriented Programming) principles with real-world examples in Java. Answer
Model answer: 1. Encapsulation (data hiding via private fields/getters). 2. Abstraction (hiding implementation complexity). 3. Inheritance (code reusability). 4. Polymorphism (method overriding/overloading).
What is the time and space complexity of QuickSort vs MergeSort? Answer
Model answer: QuickSort: Average O(N log N) time, O(log N) space. Worst O(N^2). MergeSort: Guaranteed O(N log N) time, but requires O(N) auxiliary space.
Explain the difference between SQL Indexing (B-Tree vs Hash) and when not to use an index. Answer
Model answer: Indexes speed up SELECT queries via B-Trees. However, they slow down INSERT, UPDATE, and DELETE operations because indexes must be updated on disk. Avoid on low-cardinality columns (e.g., boolean flags).
What happens under the hood when you enter a URL in a browser? Answer
Model answer: 1. DNS lookup (resolves IP). 2. TCP 3-way handshake (SYN, SYN-ACK, ACK). 3. TLS negotiation for HTTPS. 4. HTTP GET request sent. 5. Server responds with HTML/CSS/JS. 6. Browser renders DOM & CSSOM tree.
What is the difference between REST and GraphQL APIs? Answer
Model answer: REST uses multiple fixed endpoints with possible over/under-fetching. GraphQL uses a single endpoint allowing clients to query exact fields in a single request.
Behavioural & HR questions 3
Why do you want to join Paytm as a Backend- Senior Technical Lead?
Highlight Paytm's market reputation, recent tech innovations, and how your skills in Java directly solve their team's objectives.
Highlight Paytm's market reputation, recent tech innovations, and how your skills in Java directly solve their team's objectives.
Describe a challenging bug or academic project roadblock and how you resolved it.
Use the STAR method: Situation (project context), Task (what needed solving), Action (specific tools/logic applied), Result (quantifiable positive outcome).
Use the STAR method: Situation (project context), Task (what needed solving), Action (specific tools/logic applied), Result (quantifiable positive outcome).
How do you handle strict deadlines or sudden scope changes?
Explain your prioritization strategy, proactive communication with mentors/peers, and agile mindset.
Explain your prioritization strategy, proactive communication with mentors/peers, and agile mindset.
Not disclosed
Noida, India
1) 6 to 9 years of hands-on backend engin…
