interviewing great developers: reverse engineering interview coaching to create great candidates

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Interviewing A-PlayersReverse Engineering Interview Coaching

to Create Great Candidates

Gayle Laakmann McDowell

June 2014

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Gayle Laakmann McDowell

<dev>

</dev>

Author Interview Coach Interview Consulting

(CS) (MBA)

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What I Coach

Download at: CrackingTheCodingInterview.com

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Traditional Dev Questions

Startups “Elite” Other

Behavioral/Experience

Knowledge-Based

System Design/Architecture

Algorithms/Problem-Solving✔?

✔?✔

??

Disclaimer: So. Many. Exceptions.

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How can you help candidates be their best?

Behavioral Problem Solving

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Behavioral Questions: Mistakes

• Underplaying individual contributions• Using “we” not “I”• Not elaborating on actions

• Don’t assume• Probe for details

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Generalist vs. Specialist

• Generalist (algorithms/problem-solving):– Reasonable test of intelligence if done well– Hires highly adaptable people– BUT necessitates that you will train people

• Specialists (knowledge & experience):– Tests that someone can “hit the ground running”– BUT is the knowledge actually difficult to acquire?

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Algorithm Questions

“Problem-Solving Questions”

= Solving a problem you have NOT seen before.

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Problem-Solving Questions

few false positives(only good people pass)

but…

lots of false negatives(many good people fail)

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Why Problem-Solving Questions Work

• Smart people do good work.• Hires adaptable people

So why so many false negatives?

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Why Smart People Fail

1. Knowledge gaps2. Intimidation3. Arbitrary questions4. Not knowing how to be good

These are [partially] solvable problems.

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Why Help Candidates Be Great?

• Goal: good employees, not good candidates.• Do you want to eliminate…–Everyone who doesn’t know ___?–People who are insecure?–People who are bad at interviewing?–People at random?

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1: Knowledge-Gaps (Why?)

• Not knowing fundamental CS knowledge– Especially older people!

• Obscure CS knowledge being tested– Making questions “hard” via knowledge.

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2: Intimidation (Why?)

• Low self-confidence.• Scary questions.• Candidates misunderstanding interview goals.• Interviewers being [unintentionally] rude.

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3: Arbitrary Questions (Why?)

• Well-known questions.• Easy questions.• “A-Ha” moments & singular hurdles.

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4: Not Knowing How To Be Good

• Didn’t use an example.• Tried to rush the process.• Didn’t walk through problem.

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Design Around This

1. Decide what you value.2. Ask the right questions.3. Give candidates tools to prepare.4. Train your interviewers.

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1. Decide What You Value

• Is problem-solving skills a top priority?• What sorts of specialist skills do you need?• Are fundamentals of CS sufficient?

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2. Ask the Right Questions

• Right topics:– Avoid scary topics.– Require only basic CS knowledge.

• Right difficulty:– Medium & hard problems. – Avoid common problems.

• Logical path with multiple insights.

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3. Give Candidates Tools to Prepare

• Tell them:– What to expect.– How they’ll be evaluated.– Struggling is normal.

• Links to preparation resources.

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4. Train Your Interviewers

• How to design good questions.• Be extra nice to candidates.• Coach candidates to be great

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4b. Coach Candidates To Be Great

• Encourage the right example.• Remind them of details.• Don’t let them dive into code.• Encourage shifting gears.• POSITIVITY & SENSITIVITY

A good coach can make a HUGE difference!

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Need The Right Infrastructure

• Interview training• List of good & bad questions -- and why• Standard resource sheets for candidates• Feedback from candidates• Assigned roles• Continuous evaluation & shadowing

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