100+ Senior Technical Lead Interview Questions and Answers

To find the median in SQL, you can use the NTILE() function to divide the data into two halves and then calculate the average of the middle values.

• Use the NTILE() function to divide the data into two halves

• Calculate the average of the middle values to find the median

• Consider handling cases where the number of values is even or odd

Microservices offer scalability and flexibility but can increase complexity and require careful management.

• Pros: Scalability, flexibility, independent deployment, technology diversity

• Cons: Increased complexity, communication overhead, data consistency challenges

• Example: Netflix uses microservices to handle millions of requests daily

• Example: Amazon migrated to microservices to improve agility and scalability

To remove an element from a circular linked list, we need to update the pointers of the previous and next nodes.

• Find the node to be removed

• Update the pointers of the previous and next nodes

• Free the memory of the removed node

Use C++ to write an input stream to a file.

• Open the input stream and output file streams in C++.

• Read from the input stream and write to the output file stream.

• Close both streams after writing is complete.

HCL Commerce can be installed using the Installation Manager tool provided by HCL.

• Download the Installation Manager tool from the HCL website.

• Launch the Installation Manager and select the HCL Commerce package to install.

• Follow the prompts and provide the necessary information such as database credentials and installation directory.

• Once the installation is complete, configure the HCL Commerce instance using the Configuration Tool.

• Test the installation by accessing the HCL Com...read more

MS Project architecture includes components like Project Server, Project Web App, Project Professional, and Project Online.

• Project Server is the central component that stores project data and manages access

• Project Web App is the web-based interface for accessing and managing projects

• Project Professional is the desktop application for creating and editing project plans

• Project Online is the cloud-based version of Project Server for online project management

Code to get unique numbers from array of strings

• Convert array of strings to array of integers

• Use a Set to store unique numbers

• Convert Set back to array if needed

A test plan can be created by identifying objectives, defining scope, selecting test cases, and determining resources.

• Identify objectives and goals of testing

• Define scope and boundaries of testing

• Select test cases based on objectives and scope

• Determine resources needed for testing

• Include timelines and milestones in the plan

• Review and update the plan regularly

Test estimations can be done by breaking down the testing tasks, identifying dependencies, and using historical data.

• Break down testing tasks into smaller, manageable units

• Identify dependencies between tasks

• Use historical data to estimate time and effort

• Consider the complexity of the system being tested

• Involve the testing team in the estimation process

• Use estimation techniques such as PERT or Three-Point Estimation

• Adjust estimates based on risk and uncertainty

AUTOSAR layers provide a structured approach to software architecture, with BSW layer offering low-level hardware access and services.

• AUTOSAR architecture consists of four layers: Application Layer, RTE Layer, BSW Layer, and MCAL Layer.

• BSW Layer provides standardized services for accessing hardware and managing resources, such as communication stacks, diagnostics, and memory management.

• Advantages of BSW Layer include portability, reusability, and scalability of software compo...read more

CI/CD pipelines can be set up using tools like Jenkins, GitLab CI/CD, or AWS CodePipeline.

• Choose a CI/CD tool that suits your project requirements.

• Create a pipeline that includes stages for building, testing, and deploying your code.

• Integrate the pipeline with your version control system.

• Automate the pipeline to trigger on code changes.

• Monitor the pipeline for errors and failures.

• Continuously improve the pipeline based on feedback and metrics.

We use a variety of tools including programming languages, frameworks, version control systems, and project management tools.

• Programming languages such as Java, Python, C++, etc.

• Frameworks like Spring, React, Angular, etc.

• Version control systems like Git, SVN, Mercurial, etc.

• Project management tools such as Jira, Trello, Asana, etc.

RE Framework is a template for building automation processes in UiPath Studio.

• RE stands for Robotic Enterprise Framework

• It is a standardized template for building automation processes

• It follows a modular approach with reusable components

• It includes exception handling, logging, and reporting functionalities

• It helps in building scalable and maintainable automation solutions

The null coalescing operator (??) is used to provide a default value for nullable types if the value is null.

• Null coalescing operator (??) is used to return the left-hand operand if the operand is not null, otherwise it returns the right-hand operand.

• Example: int? x = null; int y = x ?? -1; // y will be -1 since x is null

• It is commonly used with nullable types to provide a default value if the nullable type is null.

Life cycle hooks are methods that allow you to tap into the lifecycle of a component in Angular.

• ngOnInit - called after Angular has initialized all data-bound properties

• ngOnChanges - called when an input property changes

• ngOnDestroy - called before the component is destroyed

• ngAfterViewInit - called after Angular has fully initialized a component's view

ELK is a monitoring tool that stands for Elasticsearch, Logstash, and Kibana.

• ELK is a combination of three open-source tools: Elasticsearch, Logstash, and Kibana.

• Elasticsearch is a search and analytics engine that stores and indexes data.

• Logstash is a data processing pipeline that ingests, processes, and sends data to Elasticsearch.

• Kibana is a visualization tool that allows users to interact with data stored in Elasticsearch.

• ELK is commonly used for log management, monitoring...read more

Coding is used to create software programs and applications.

• Coding allows us to instruct computers to perform specific tasks.

• It helps in automating processes and solving complex problems.

• Coding enables the development of software that powers various industries.

• It allows for customization and flexibility in creating solutions.

• Coding is essential for creating websites, mobile apps, and software systems.

• Examples: Writing code to build a website, creating algorithms for data anal...read more

Static middleware is used in web development to serve static files such as HTML, CSS, and images.

• Static middleware is a piece of Express.js middleware that serves static files from a specified directory.

• It is commonly used to serve files like HTML, CSS, images, and JavaScript.

• Static middleware can be added to an Express application using the 'express.static' method.

• Example: app.use(express.static('public')) will serve files from the 'public' directory.

Kubernetes is a container orchestration platform that automates deployment, scaling, and management of containerized applications.

• Kubernetes uses a master-slave architecture with a control plane and worker nodes.

• The control plane manages the overall state of the cluster and schedules workloads to worker nodes.

• Worker nodes run the containers and report back to the control plane.

• Kubernetes uses declarative configuration to define desired state and automatically reconcile with a...read more

AWS Redshift is a fully managed data warehouse service in the cloud, optimized for high performance analytics.

• Redshift follows a Massively Parallel Processing (MPP) architecture

• It consists of leader nodes and compute nodes

• Leader node manages client connections and coordinates compute nodes

• Compute nodes store data and perform queries in parallel

• Redshift Spectrum allows querying data in S3 directly without loading into Redshift

Closure in JavaScript is the combination of a function and the lexical environment within which that function was declared.

• Closure allows a function to access variables from its outer scope even after the outer function has finished executing.

• It is created every time a function is created, and it maintains a reference to the variables from its outer scope.

• Closure is commonly used in event handlers, callbacks, and maintaining state in functional programming.

ConcurrentHashMap is a thread-safe version of HashMap in Java.

• ConcurrentHashMap allows multiple threads to read and write to the map concurrently without causing a ConcurrentModificationException.

• It achieves this by dividing the map into segments, each with its own lock, allowing multiple threads to access different segments simultaneously.

• ConcurrentHashMap is part of the java.util.concurrent package in Java.

• Example: ConcurrentHashMap map = new ConcurrentHashMap<>();

Sets are collections of unique elements with no specific order, while groups are collections of elements with a defined structure and operations.

• Sets do not allow duplicate elements, while groups can have repeated elements.

• Sets do not have a specific order, while groups may have a defined structure.

• Sets are often used in mathematical contexts, while groups are used in algebra and other areas of mathematics.

Authentication process in API involves verifying the identity of the user or application accessing the API.

• User or application sends a request to the API with credentials (e.g. username and password, API key, token)

• API server validates the credentials provided by the user or application

• If credentials are valid, API server generates a token or session ID and sends it back to the user or application

• User or application includes the token or session ID in subsequent requests to a...read more

Implemented a scalable microservices architecture for a large e-commerce platform

• Designed and implemented a containerized architecture using Docker and Kubernetes

• Implemented service discovery and load balancing using Consul and Nginx

• Implemented a message broker using RabbitMQ for asynchronous communication between services

• Implemented a centralized logging and monitoring system using ELK stack and Prometheus

• Reduced deployment time from hours to minutes and improved system reli...read more

Browser interprets JSX by transforming it into regular JavaScript using a transpiler like Babel.

• JSX is not directly understood by browsers, so it needs to be transpiled into regular JavaScript

• Babel is a popular transpiler used to convert JSX into JavaScript

• The transpiled JavaScript code is then executed by the browser

Telco security involves protecting telecommunications networks and data from cyber threats. It includes protocols like SSL, IPSec, and VPN.

• Telco security focuses on securing telecommunications networks and data from cyber attacks

• Protocols like SSL (Secure Sockets Layer), IPSec (Internet Protocol Security), and VPN (Virtual Private Network) are commonly used in telco security

• Encryption and authentication are key components of telco security to ensure data confidentiality and i...read more

LOD in Tableau stands for Level of Detail and refers to the ability to control the level of aggregation in visualizations.

• LOD expressions allow you to compute values at different levels of detail in Tableau.

• There are three types of LOD expressions: INCLUDE, EXCLUDE, and FIXED.

• INCLUDE LOD expressions compute values at the specified level of detail and then aggregate them up to the view level.

• EXCLUDE LOD expressions exclude the specified dimension from the view level of detail....read more

Mirror binary tree without recursion by swapping left and right child nodes iteratively

• Start with the root node and swap its left and right child nodes

• Then move to the left child node and swap its left and right child nodes

• Repeat the process for all nodes in the tree until all nodes are mirrored

Spring Boot allows setting up multiple data sources for database connectivity.

• Define multiple data source configurations in application.properties or application.yml

• Create separate DataSource beans for each data source

• Use @Primary annotation to specify the primary data source

• Use @Qualifier annotation to specify the data source for specific repositories or services

• Configure JPA or JDBC templates for each data source

UDS protocol stands for Unified Diagnostic Services protocol used in automotive industry for communication between vehicle ECUs.

• UDS protocol is used for diagnostic communication between electronic control units (ECUs) in vehicles.

• It is standardized by ISO 14229-1 and ISO 14229-2.

• UDS allows for diagnostic services such as reading and clearing diagnostic trouble codes, accessing ECU information, and performing routines like flashing ECU firmware.

• It uses a request-response mecha...read more

Performance process involves setting goals, monitoring progress, providing feedback, and evaluating results.

• Setting clear and specific performance goals for individuals or teams

• Regularly monitoring progress towards those goals

• Providing feedback on performance to help improve

• Evaluating results to determine success and areas for improvement

Check if a string is a palindrome

• Iterate through the string from both ends and compare characters

• Ignore spaces and punctuation while checking for palindrome

• Convert string to lowercase for case-insensitive comparison

End-to-end life cycle management involves overseeing a project from conception to completion.

• Understand project requirements and goals

• Create a detailed project plan

• Assign tasks and responsibilities to team members

• Monitor progress and make adjustments as needed

• Ensure project is delivered on time and within budget

YTD stands for Year-to-Date and MTD stands for Month-to-Date, both are used to track financial performance over a specific period of time.

• YTD refers to the period starting from the beginning of the current year up to the present date.

• MTD refers to the period starting from the beginning of the current month up to the present date.

• YTD and MTD are commonly used in financial reporting to analyze performance trends.

• For example, if today's date is July 15th, the YTD period would be...read more

Dependency injection is a design pattern where components are given their dependencies rather than creating them internally.

• Dependency injection helps in achieving loose coupling between classes.

• It allows for easier testing by providing mock dependencies.

• There are three types of dependency injection: constructor injection, setter injection, and interface injection.

SoLid principles are a set of five design principles for writing clean, maintainable, and scalable code.

• Single Responsibility Principle: A class should have only one reason to change.

• Open/Closed Principle: Classes should be open for extension but closed for modification.

• Liskov Substitution Principle: Objects of a superclass should be replaceable with objects of its subclasses without affecting the program's correctness.

• Interface Segregation Principle: Clients should not be fo...read more

Basic automation in UiPath involves creating workflows using drag and drop activities to automate repetitive tasks.

• Identify the task to be automated

• Create a new project in UiPath Studio

• Use drag and drop activities to build the workflow

• Test and debug the workflow

• Deploy the workflow to run on a schedule or trigger

• Examples include automating data entry, file management, and web scraping

MCQs in UiPath and automation

• MCQs are multiple choice questions that test knowledge in UiPath and automation

• They can cover topics such as activities, selectors, variables, and workflows

• Examples of MCQs include: What is the purpose of the 'Type Into' activity? and What is the difference between a dynamic and static selector?

ASP.NET is a web development framework within the .NET platform, while .NET is a broader framework for building various types of applications.

• ASP.NET is specifically for web development, while .NET is a general-purpose framework.

• ASP.NET includes technologies like Web Forms, MVC, and Web API for building web applications.

• .NET encompasses languages like C#, VB.NET, and F# for building desktop, web, and mobile applications.

• ASP.NET is built on top of the .NET framework, utilizing...read more

Identifying bottlenecks in a system is crucial for improving performance.

• Monitor system performance metrics such as CPU usage, memory usage, disk I/O, and network traffic.

• Identify slow queries or operations in databases.

• Analyze code for inefficiencies and optimize where necessary.

• Check for resource contention issues such as locks or queues.

• Consider scalability limitations in the system architecture.

High performance, cross-platform compatibility, open-source, modern development features

• Cross-platform compatibility allows for deployment on various operating systems

• High performance due to optimized runtime and just-in-time compilation

• Open-source community support for continuous improvement and updates

• Modern development features like dependency injection, modular architecture, and improved performance monitoring

• Example: .Net Core allows for easy migration of existing .Net a...read more

Git rebase is a command used to integrate changes from one branch to another by applying them on top of the target branch.

• Rebase rewrites the project history by creating new commits for the changes.

• It is used to keep the commit history clean and linear.

• It is an alternative to merging and can be used to resolve conflicts.

• It should not be used on public branches as it can cause conflicts for other users.

• Example: git rebase feature-branch master

I have worked on a variety of applications including e-commerce platforms, CRM systems, and data analytics tools.

• E-commerce platforms

• CRM systems

• Data analytics tools

Reverse a given array of strings

• Iterate through each string in the array

• Reverse each string using built-in functions or manual reversal

• Store the reversed strings back in the array

Telco cloud refers to the virtualized infrastructure and services that enable telecommunications companies to deliver network functions and services through cloud computing technologies.

• Telco cloud allows telecom operators to virtualize network functions and services, enabling greater flexibility and scalability.

• It helps reduce operational costs and accelerate service delivery by leveraging cloud computing technologies.

• Examples of telco cloud services include virtualized radi...read more

I have extensive systems engineering experience in designing, developing, and implementing complex systems.

• Designed and implemented a complex data management system for a large financial institution

• Led a team of engineers in developing a new software platform for a healthcare company

• Developed and implemented a system for tracking and analyzing customer data for an e-commerce company

• Experience with systems engineering methodologies such as Model-Based Systems Engineering (MBSE...read more