Derrick Ko

Product Manager at Lyft. Product guy. Founded a startup.

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Why CSS Testing Could Be Huge

Design has established itself as a differentiating factor in web applications, and along with it, the importance of the visual experience. Testing visuals is usually done by manual inspection, which can get tedious. Integration testing misses out on that very aspect of how your application should look at any given time.

Fortunately, the visual experience on the web is controlled by CSS, and CSS is testable. Frameworks like Needle have taken a stab at it. But I find them too cumbersome to be useful; Needle compares your pages to gold-standard screenshots.

So I was really excited when my friend and ex-colleague Winston released Cactus. Cactus takes a more practical approach and tests based on the computed CSS of the document.

But hold on, isn’t it overkill to test your CSS?

No it’s not.

You do it already

You already have a style guide. You already know what classes and styles each...

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Rewrites are strangely attractive. Developers love to work on a sparkling clean code base. But in reality, there’s much more to a rewrite beneath the surface. Like all those implementation subtitles and edge cases you took for granted.

Rewrites are tempting, but can also be deceptively complex. Don’t rush into one. Have a well thought out plan. It worked for us; we launched smoothly and right on schedule.

Join the discussion on Hacker News.

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What Does A University Optimize For?

As per the student’s request, I have removed the contents of this post.

I do still have one question though - how does NOC measure success?

Considering that over a hundred students go through NOC each year, I don’t see even 10% of the entire cohort, since inception, starting a company or working at a startup.

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A rallying call

There’s work and there’s your life’s work.

The kind of work that has your fingerprints all over it. The kind of work that you’d never compromise on. That you’d sacrifice a weekend for. You can do that kind of work at Apple. People don’t come here to play it safe. They come here to swim in the deep end.

They want their work to add up to something.

Something big. Something that couldn’t happen anywhere else.

That’s right, Apple. In a widely circulated note to new hires. Not hiring copy from that new startup.

Some argue that it’s faux inspirational, exploitative copy. I see an example of Apple’s dedication to a polished experience. Most companies tend to garble up their internal messaging into high level, un-motivational corporate speak. Apple still maintains that attention to detail, that style of language, even internally.

And to anyone trying to make an impact at/with their...

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Startups Mess with Maslow

Maslow's hierarchy of needs

Maslow’s hierarchy of needs is a popular theory in psychology that describes human motivations. The hierarchy is commonly portrayed with a pyramid, with our most essential needs towards the base. Many live their lives in accordance to Maslow’s theory, especially when it comes to their job.

A typically ideal job comfortably helps you fulfill your physiological and safety needs. With the stability, you would be able to pursue love and belonging. You are motivated to stay on and seek a promotion, with an increased sense of achievement as you climb to the top. And finally, according to Maslow, you reach self-actualization after achieving the levels below it. In other words, only after many years on the job.

But when you go out on your own, you hit self-actualization immediately. A shortcut with sacrifices, if you will.

Friends and family get pushed up the hierarchy as they temporarily...

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The consumerization of food

You can now sit down to a complete dinner of faux gourmet items like Greece’s famous Kalamata olives and domestic Spanish or Italian cured ham, followed by a pasta course made with “Italy’s” world renowned San Marzano tomatoes and topped with Parmigiano-Reggiano, “The King of Cheeses.” The main course? Kobe beef of course, maybe topped with Kobe pork, all washed down with Champagne and red Burgundy.

Top it off with a glass of Port or a nice cup of Darjeeling tea, and you will have just consumed a meal that may well have been produced entirely in a factory down the street from you.

This is a consequence of consumerism.

Food is an integral part of a country’s cultural heritage. And producers disrespect a culture when they half heartedly copy and falsely market food with a historical lineage. In some circles, we call that bootlegging.

But of course, nothing matters as long as consumers...

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Living With Dignity

From time to time, I’ll feature pieces by great guest writers. If you’ve something you’d love to see up here, drop me a note.

This week’s writer has asked to remain anonymous.

Yesterday evening I watched actor Chis Larner tell an honest tale of his journey bringing his ex-wife to the Dignitas clinic in Switzerland to commit physician-assisted suicide. She was in her 60s suffering from late stages of multiple sclerosis, leaving her with limbs almost completely non-functional, doubly incontinent, in constant pain, fatigued after a 15-minute conversation and consequently housebound. However, her mind was fully functional, and she was destined to continued deterioration for the next decade at least. In her words, “I don’t want to die. But I don’t want to live, not like this.”

[Dignitas]( is a Swiss charity which has assisted over a thousand suicides since it was founded...

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The intricacies of venture capital

Ben Horowitz’s reaction to the reactions:

Despite Instagram’s awesome performance and our monstrous return, a number of articles have come out criticizing us for not making even more money on our investment. Ordinarily, when someone criticizes me for only making 312 times my money, I let the logic of their statement speak for itself.

And the intricacies of venture capital:

After speaking with both entrepreneurs and much internal discussion, we concluded that funding Kevin to compete with Dalton would be a violation of the original implicit commitment we made to Dalton—to not fund competitors to PicPlz. On the other hand, funding Dalton did not violate our implicit agreement with Kevin because he changed his business—we’d funded Burbn not Instagram.

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Your Users Aren’t You

As with any review site, we had to deal with user ratings. In our case, our users rated a place between 0 (bad) to 10 (great!).

One straightforward approach to aggregate ratings is to use a simple average. But that comes with an inherent problem. The moment something new is given a 10, it shoots right to the top.

So we naively decided to use a Bayesian average based rating system instead.

To paraphrase Wikipedia:

In a calculation of an average review score of a book where only two reviews are available, both giving scores of 10, a normal average score would be 10. However, as only two reviews are available, 10 may not represent the true average had more reviews been available.

The review site may instead calculate a Bayesian average of this score by adding the average review score of all books in the store to the calculation. For example, by adding five scores of 7 each, the...

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Starving for an education

Note: At the time of posting, Alvin painted a scenario of an aspiring engineer rejected admission to a university. Since then, this premise has been heavily disputed. He apparently willfully misrepresented himself. If those are the facts, he has mislead many people who genuinely supported him.

That said, I’m leaving the post up in the name of openness.

Oh the drama.

Hello, my name is Alvin Wang, and I’m 21 years old. Recently, my application to pursue a degree in Computer Science at National University of Singapore was rejected.

I truly enjoy developing applications using Java, C, Visual Basic, Javascript. Apart from school, I have also taught myself how to design interfaces in Photoshop, craft websites using web standards in HTML, CSS, PHP, and have been at it since I was 13. I am currently delving into iOS development with Objective-C.

I am starving for this opportunity.


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