Finly Software Engineer Interview: Rounds, Questions and Preparation

What the job involves

Software Engineers at Indian SaaS and B2B product companies like Finly build and maintain web-based platforms that help businesses manage finance, operations, or customer relationships. Day to day, they write clean code, debug issues, collaborate with product managers and designers, and ensure the software is scalable and secure for enterprise clients. Freshers typically start with feature development, bug fixes, and writing tests under the guidance of senior engineers.

Role and Technical Knowledge

1. 1

   What do you understand about the day-to-day responsibilities of a software engineer in a SaaS product company like Finly?

   Mention building features, fixing bugs, writing tests, collaborating with cross-functional teams, and ensuring scalability for multiple clients.

2. 2

   Explain the difference between a monolithic and a microservices architecture. Which one would you prefer for a B2B SaaS product and why?

   Highlight that microservices offer scalability and independent deployment, which suits multi-tenant SaaS, but monoliths are simpler for early-stage products.

3. 3

   How would you design a database schema for a simple expense management feature in a B2B SaaS application?

   Cover tables for users, expenses, categories, and approvals, with foreign keys and indexing for performance.

4. 4

   What are REST APIs and why are they important in SaaS products?

   Explain that REST APIs allow different services and clients to communicate over HTTP, enabling integrations and mobile apps.

Practical Scenarios

1. 5

   You are asked to fix a bug where a customer's invoice total is calculated incorrectly only when multiple currencies are involved. How would you approach this?

   Describe reproducing the issue, checking currency conversion logic, writing a test case, and fixing the rounding or exchange rate handling.

2. 6

   How would you handle a situation where your code works on your local machine but fails in the production environment of a SaaS product?

   Talk about checking environment variables, logs, database differences, and using staging environments to replicate production.

3. 7

   Suppose you need to add a new feature to an existing B2B SaaS application that many clients use. How do you ensure you don't break existing functionality?

   Mention writing unit and integration tests, using feature flags, and doing a phased rollout with monitoring.

4. 8

   If you had to optimize a slow SQL query in a SaaS application, what steps would you take?

   Cover analyzing the query plan, adding indexes, avoiding SELECT *, and caching frequent results.

Behavioural and HR

1. 9

   Why do you want to work in a SaaS product company like Finly rather than a service-based IT company?

   Show interest in building products, working with modern tech stacks, and seeing your work used by many businesses.

2. 10

   Describe a time when you had to learn a new technology quickly for a project. How did you go about it?

   Use a specific example, mention resources used, and highlight the outcome and what you learned.

3. 11

   How do you handle feedback or criticism on your code from a senior engineer?

   Emphasize being open to feedback, asking questions, and treating it as a learning opportunity to improve code quality.

4. 12

   Where do you see yourself in the next two years in a product-based company?

   Show ambition to grow into a senior engineer role, take ownership of modules, and contribute to architecture decisions.

Problem Solving and Coding

1. 13

   Write a function to find the first non-repeating character in a string. Explain your approach.

   Use a hash map to count frequencies, then iterate to find the first character with count 1. Discuss time and space complexity.

2. 14

   Given a list of transactions with amounts, write a function to find the pair that sums to a target amount. How would you optimize it?

   Use a hash set for O(n) time, and mention edge cases like negative amounts or no solution.

3. 15

   Explain how you would reverse a linked list. What are the edge cases?

   Describe iterative pointer manipulation, and mention empty list, single node, and preserving the head reference.

4. 16

   How would you detect a cycle in a linked list?

   Use Floyd's cycle-finding algorithm (tortoise and hare) and explain why it works with O(1) space.