Sunday 16 December 2007

Senior Developer Interview Questions

We had a couple of senior developer tenders go out at work recently and when it came time to interview the applicants I was asked to put together a test to flush out the wannabes. I've been on the receiving end of these tests in the past and considering this test would be written in the twenty to thirty minutes before a three-panellist interview, I thought I wouldn't be too hard. I'd say most of these questions are analyst programmer questions, if not junior dev questions, although I did through in a few tricks to gauge experience and I also left some questions fairly open in an attempt to understand the applicant's though process. If the applicant couldn't complete the test in the time period given, that would be okay too.

I've included the job criteria headers to help you figure out what I was looking for in each answer; not every question fits within a specific heading. The headings were printed on the test sheet.

The Perth .NET developer market has been on fire since I arrived two years ago and SharePoint work is going through the roof; as a result, we only had a single applicant put forward for the two or three tenders that went out. When and if we have more people across this test I'll attempt to generalise the results and post an update to this post on the effectiveness of this test.

I haven't included the answer here because like I said, some of them are fairly open and a lot of them should be fairly obvious if you've done an undergraduate CS course.

At least 5 year of software development experience and at least 2 year experience developing MS .NET applications

  1. Describe the difference between the execution environments for C++, C#, and Javascript
  2. Is C# a weakly-typed language? Why or why not?
  3. When should performance optimisation occur?
  4. List three problems with this code. Bonus: how could it be improved if you were using .NET 3.5?

    private string someVar = 1234;

    public string SomeVar
    if (string.IsNullOrEmpty (someVar))
    someVar = “5678”;

    return SomeVar;
    someVar = val;

  5. When would you mark a class with the internal visibility modifier?
  6. What’s the difference between a struct and a class? Are structs allocated on the heap?
  7. The property invocation below may return a null result. Rewrite the code to prevent the second line from throwing.

    object result = Employee.Address;
    result.ToString ();

Working knowledge of full lifecycle development methodologies, process and standards and project management; sound knowledge of object oriented system design and development...

  1. List one section heading you might expect to find in each of the following documents:

    · A functional specification
    · A technical specification
    · A UAT test case
  2. List three tasks you would complete before checking in a new class to the Tourism WA source control system.Name each component in the following diagram and briefly explain the relationship between Vehicle and Door:
  3. What is a use case?
  4. Briefly describe the difference between a class, an interface, and a type
  5. Briefly describe a software design pattern you’ve used on a past project and indicate how it helped or hindered code maintenance. Alternatively, describe a design pattern employed by ASP.NET.
  6. After designing a new system, your project manager asks you to estimate construction time for yourself and a junior developer. This is the first time the department has built this type of system and you haven’t previously worked with the junior developer. List three techniques you would consider to ensure your estimate is as accurate as possible

Solid understanding of internet protocols, web development mark-up languages and web standards...

  1. Draw a simple diagram showing the location of a reverse proxy in relation to a database server, a web server, the internet, and a client
  2. Using only inline CSS and DIV tags, write the HTML to produce a three-column, one row table (don’t worry about borders). Don't use tables.
  3. Will the Hello World! text be rendered green, red, or blue by the browser?

    span { color: green }
    #makeItRed { color: red; }
    .makeItBlue { color: blue; }
    <span id="makeItRed" class="makeItBlue">Hello World!</span>
  4. List three key components of this schema fragment. How many ReservationRequest elements are allowed in an XML document validated against this schema?

<xs:element name="Control">
<xs:element name="ControlID" type="xs:int" minOccurs="0" />
<xs:sequence minOccurs="0">
<xs:element name="ReservationRequest">
<xs:element name="InDate" type="xs:dateTime" />
<xs:element name="Period" type="xs:int" />
<xs:element name="Adults" type="xs:int" />
<xs:element name="Children" type="xs:int" />
<xs:element name="Infants" type="xs:int" /> </xs:sequence>

Sound knowledge of the Microsoft .NET framework class libraries, ASP.NET and Web Services

  1. What improvements does the .NET 2.0 System.Collections.Generic namespace offer over the System.Collections namespace from previous versions of the framework?
  2. List two key differences between a user control and a web control
  3. Compare the .NET application cache and the ASP.NET output cache
  4. Write a call to the Format ( ) method of the String class to return the string “Sam is 38 years old.” Assume you have a variable declared and initialised as follows:

    int age = 38;

    Give an example of a situation when you would use a StringBuilder instead

  5. Describe the difference between application state, session state, and view state. Discuss session state in relation to scalability and suggest an alternative.
  6. List two techniques to secure web service communication on the internet

Ability to perform unit and integration testing...

  1. What purpose do the following serve when debugging a section of code:

    · The F11 key on your keyboard
    · The Immediate window

  2. Briefly describe the concept of “regression testing”