Parallel Universe, Same Hiring Process: An Interview excerpt for a Technical Lead Position

Are you curious about what it takes to be a successful technical lead in an alternate dimension? Sorry to disappoint you, but we won't be exploring that in this post. Instead, let's focus on what we know best: the technical skills and experience required for the role in our own reality. But the hiring process can be a maze of buzzwords and jargon that can make your head spin. Fear not! In this blog post, we'll be sharing an interview excerpt from a hypothetical tech lead candidate, and looking at how their skills and experience stack up to the job requirements. Whether you're in this dimension, the next, or somewhere in between, we hope you'll find some helpful insights and a few chuckles along the way.

Job requirement : As a technical lead with 10 years of experience, you are expected to have a deep understanding of software development best practices and the ability to lead a team of developers to deliver high-quality software. You should have strong skills in C# and experience with Sql Server, .Net core, and Azure cloud. You'll be responsible for leading the design and implementation of complex systems, ensuring that the team delivers on-time and on-budget. Additionally, experience with agile methodologies, DevOps, and cloud technologies will be highly valued.

Interviewer: Let's start with a classic question. Can you tell us a little bit about yourself and your experience as a technical lead?

Candidate: Of course! I've been working in the software development industry for over 10 years now, during which I have gathered extensive experience in various roles. I have been serving as a technical lead for the past 10 years, during which I have led the development of several large-scale projects, including a cloud-based SaaS application that required extensive use of Azure DevOps for continuous integration and deployment.

As a technical lead, my responsibilities have included designing and developing software architectures, overseeing the development process, collaborating with cross-functional teams, and ensuring the successful delivery of projects. My technical expertise and leadership skills have allowed me to successfully manage and deliver complex projects within tight deadlines and budget constraints.

I'm also very comfortable working with .Net core and have used it to develop several web applications, REST APIs, and microservices. I have used .NET Core for developing solutions for diverse industries, including healthcare, finance, and education. My experience with .NET Core has enabled me to create efficient and reliable applications that meet the requirements of the clients.

So I can say that my experience as a technical lead, combined with my expertise in .NET Core and Azure DevOps, has equipped me with the skills necessary to take on the role of a Technical Lead for your organization.

Interviewer: Great, it sounds like you have a lot of experience with the technologies we are looking for. Let's dive a bit deeper into your technical skills. Could you give me an example of a particularly challenging technical problem you faced, and how you went about solving it?

Candidate: Absolutely. One of the most challenging technical problems I've faced was during the development of a healthcare application, which required integrating multiple systems and databases. The project required integrating data from multiple sources such as EMR systems, medical imaging devices, and patient monitoring systems. The data was stored in various formats such as HL7, DICOM, and proprietary formats, which made the integration process challenging.

To overcome this challenge, I worked with my team to design a data integration process that used C# and SQL Server. We first extracted the data from the various sources and then transformed it into a standardized format using custom C# scripts. The transformed data was then loaded into a centralized SQL Server database for further processing and analysis.

To ensure that the data integration process was reliable and scalable, we used Azure DevOps for continuous integration and deployment. We created automated tests that ran on each code check-in to ensure that the changes didn't break any existing functionality. We also used Azure DevOps pipelines to automate the deployment process, which significantly reduced the time and effort required for testing and deployment.

Interviewer: Could you walk me through how you tackled any potential performance or scalability issues that may have arisen during this process?

Candidate: Absolutely. Performance and scalability were definitely major concerns during this project, especially given the large volume of data we were dealing with. To address these issues, we implemented a number of strategies, such as optimizing the database queries, leveraging asynchronous programming to improve the overall system responsiveness, and using distributed caching to reduce the load on the database. We also made sure to design the architecture in a way that allowed us to easily scale horizontally by adding more instances if needed. Overall, these efforts helped us to achieve the desired level of performance and scalability for the application.

Interviewer: Ok. Could you elaborate on the architecture you designed to easily scale your application horizontally by adding more instances as needed?

Candidate: When I mentioned horizontal scaling, what I meant was that we designed the application architecture to allow for easy scaling by adding more instances as needed. Specifically, we used Azure App Service to deploy and manage the application. This allowed us to easily scale the application by adding more instances when the load increased, and remove instances when the load decreased. We also implemented load balancing using Azure Traffic Manager, which evenly distributed the traffic across all instances of the application. This approach allowed us to provide a high level of availability and reliability for our users, even during periods of high traffic or demand.

Interviewer: Can you explain how you leveraged Azure App Service to enable horizontal scaling of your application? Specifically, how did you ensure that additional instances could be added seamlessly as demand increased?

Candidate: Azure App Service allows us to easily scale our application horizontally by adding more instances when the load increases. This means that instead of upgrading the hardware or server, we can add more instances of the same application on separate machines, which provides better scalability, reliability, and redundancy. With Azure App Service, we can set up auto-scaling rules based on metrics such as CPU usage, memory usage, and network traffic. This allows the application to scale up automatically when the load increases and scale down when the load decreases, ensuring that we only use the resources we need and minimize our costs.

Additionally, Azure App Service allows us to scale up and down, which means we can increase or decrease the computing power of our application. For example, we can increase the number of CPU cores or memory allocated to our application when we anticipate a peak load. This is known as vertical scaling or scale up. On the other hand, when the load decreases, we can decrease the computing power to reduce costs. This is known as vertical scaling or scale down.

Overall, with Azure App Service, we have the flexibility to scale our application both horizontally and vertically, providing us with the agility, efficiency, and cost savings we need to meet the demands of our customers.

Interviewer: Can you describe the Azure resources that you utilized to deploy your application?

Candidate: Sure, we used several Azure resources for our application deployment and management. First and foremost, we used Azure App Service to host our application and enable auto-scaling based on the load. We also used Azure SQL Database to store and manage our data, and Azure Blob Storage for storing unstructured data like images and documents. For continuous integration and deployment, we utilized Azure DevOps and Azure Container Registry to build and deploy our application. Finally, we used Azure Monitor for monitoring and logging, and Azure Key Vault to securely manage our application secrets and keys.

Interviewer: Can you explain how you utilized Azure Key Vault in your project and the specific reasons for using it?

Candidate: Sure, I'd be happy to explain. Azure Key Vault is a cloud-based service that provides a secure and centralized location to store and manage cryptographic keys, secrets, and certificates. It allows us to securely store sensitive information, such as connection strings, API keys, and other application secrets.

In our application, we needed to store various types of secrets that were required for the proper functioning of the application. We wanted to ensure that these secrets were stored securely and could be easily accessed by the application when needed. Azure Key Vault provided us with a centralized location to store these secrets, with secure access and auditing capabilities.

While Azure does provide configuration settings that can store passwords and connection strings, Azure Key Vault offers an additional layer of security and control over these sensitive items. By storing secrets in Key Vault, we can better manage access and reduce the risk of unauthorized access or accidental exposure.

Interviewer: Could you walk me through the implementation process you followed to integrate Azure Key Vault in your project?

Candidate: To implement Azure Key Vault in my project, I created an Azure Key Vault in the Azure portal & then created a new Key Vault resource in the Azure portal and provided the necessary details like name, subscription, resource group, and location. Then I added the required access policies for my application to access the Key Vault. I ensured that the access policies were scoped to the specific secrets and keys that my application needed to access. After that I created the necessary secrets in the Key Vault and stored them securely. These secrets included connection strings, passwords, and other sensitive information that my application needed to access. To access the Key Vault from my application, I used Managed Identity. I enabled Managed Identity for my application and granted it the necessary permissions to access the Key Vault. Finally, I updated my application code to retrieve secrets from the Key Vault instead of hardcoding them in the code. I used the Azure Key Vault SDK for .NET to access the Key Vault from my code.

By following these steps, I was able to securely store and retrieve sensitive information in my application using Azure Key Vault. This ensured that the sensitive information was not exposed in the code or configuration files and was only accessible to the authorized users and applications.

Interviewer: Are you aware of Liskov princinple in SOLID principles?

Candidate: Yes. I am aware & have even used in my project.

Interviewer: This is great! Can you give an example of how you applied the Liskov principle in your project?

Candidate: Certainly. In the project, we had to build a billing system that supported multiple payment gateways, including credit card, PayPal, and Stripe. Initially, we had created separate classes for each payment method, but we soon realized that these classes had several common functionalities, like processing payment, checking the balance, and sending payment confirmation.

To address this issue, we applied the Liskov principle, which states that objects of a superclass should be replaceable with objects of its subclasses without affecting the correctness of the program. We created an abstract Payment class that defined all the common functionalities and then created separate classes for each payment method that inherited from the Payment class and implemented their specific functionalities.

Interviewer: That's great. Can you explain how applying the Liskov principle benefited your project?

Candidate: Sure. By applying the Liskov principle, we were able to write cleaner and more maintainable code. It allowed us to avoid code duplication, and any changes or bug fixes needed in the future would only have to be applied to the base Payment class, which would be reflected in all the inherited payment method classes. It also made it easier to add new payment methods in the future, as we already had a solid foundation in the Payment class. Overall, applying the Liskov principle helped us achieve a better software design and ensured that our code was more scalable and maintainable.

Interviewer: Could you provide an example of the C# code you wrote to implement the Liskov principle in your project?

Candidate: Sure, here's an example of the code we implemented in the payment system project I previously mentioned:

public abstract class Payment
{
    public virtual void ProcessPayment() { }
    public virtual void CheckBalance() { }
    public virtual void SendConfirmation() { }
}

public class CreditCardPayment : Payment
{
    public override void ProcessPayment()
    {
        // code to process credit card payment
    }

    public override void CheckBalance()
    {
        // code to check credit card balance
    }

    public override void SendConfirmation()
    {
        // code to send credit card payment confirmation
    }
}

public class PayPalPayment : Payment
{
    public override void ProcessPayment()
    {
        // code to process PayPal payment
    }

    public override void CheckBalance()
    {
        // code to check PayPal balance
    }

    public override void SendConfirmation()
    {
        // code to send PayPal payment confirmation
    }
}

public class StripePayment : Payment
{
    public override void ProcessPayment()
    {
        // code to process Stripe payment
    }

    public override void CheckBalance()
    {
        // code to check Stripe balance
    }

    public override void SendConfirmation()
    {
        // code to send Stripe payment confirmation
    }
}

Interviewer: Great! Now lets move on to other areas....

Ah, that was just a tiny snippet of the exciting interview adventure! Who knows what kind of thrilling twists and turns the full interview could hold? But for now, I hope my responses gave you some helpful insights and inspiration for your own interview prep.

And remember, this blog is not just about acing your next interview. It's about feeding your curiosity and fueling your learning journey. The best way to prepare for an interview is to continuously learn and grow.

So, whether you're a seasoned developer or just starting out, take some time to explore the topics we discussed. Maybe you'll discover a new concept or tool that piques your interest. Maybe you'll find a new way to approach a problem. Or maybe, just maybe, you'll crack a smile at my attempt at humor.

Either way, I hope this blog has provided some value to you. And who knows, maybe the next time you walk into an interview, you'll be able to impress the interviewer with your knowledge and wit (and not just your shiny new tie 🙂).