When recent grad Willie Calvin went looking for a startup gig after graduation, he was excited to find a position at an artificial intelligence personal assistant company as an "AI trainer." The gig was advertised as "half product development and half reviewing the algorithm's accuracy," Calvin told Bloomberg Technology.

But in reality the job turned out to be 14-hour days of mindlessly reviewing AI-generated emails for language and tonal mistakes. "The work just ended up being way too taxing without a tangible payoff in sight," Calvin explained.

Career launch pad or modern-day sweatshop?

What this case says about whether such "chatbots" are ready for prime time is up for debate. What's certain is that Calvin's experience isn't unique. Each year many young people go looking for startup jobs hoping to contribute meaningfully and build their skills. Instead, plenty end up putting in long hours of drudgery.

They're hoping for a career launch pad. What they get is essentially a sweatshop.

How can you avoid this fate and find a startup job that, while demanding, actually advances your career, all while leaving you enough time to enjoy life and avoid burnout? I spoke with Basecamp COO and tech industry veteran Mercedes De Luca who offered a list of red flags you should watch out for.

But wait, shouldn't you expect a startup gig to be hard work?

But wait, some of you might object. This whole article is silly. You need to pay your dues and put in a little grunt work early in your career. And no one should go into startups expecting a tidy nine-to-five workday. Everyone knows this is an industry for passionate workaholics.

"It's almost an unwritten rule that urgency and long hours are associated with startups - that you're trading longer hours now for a bigger payout later," agrees De Luca. But she feels that just because the to-do list at a company is long, doesn't mean the days have to be.

If a company is focused and clear on its objectives, routine craziness shouldn't be necessary (though of course occasional all-hands-on-deck crunch times are to be expected). "I personally think seven or eight hours of real work per day is more than plenty. The hard part is that most eight-hour days include three or four hours of wasted time spent on meetings and email," she says.

Watch out for these red flags.

So on to the red flags. What are the warning signs De Luca claims startup newbies should watch out for when interviewing for a new gig?

  1. Midnight emails. "If the HR rep is emailing you at midnight and scheduling interviews for Saturday afternoons, those are red flags you should heed."
  2. Immediate email responses: "If anyone you email at the company responds immediately, you know they have an always-in-email culture. It's hard to get work done with that mentality, and it usually leaves people catching up at night and on weekends," she warns.
  3. Negative social media chatter. "If social chatter about your candidate company skews negative on platforms like Twitter, LinkedIn or Glassdoor, don't make excuses; pay attention. Reach out to your networks, and raise questions in your interview to fact-check your findings. Then, combine information with intuition to make a smart decision," De Luca instructs.
  4. A paid smartphone. "Does the company pay for internet or phone service, provide mobile devices or pay those bills? That might be either a very generous startup (which is rare) or a company that wants to own your time."
  5. Vague stock option promises: "Are the stock options described in terms of the number of shares without any context for how many shares are outstanding or how that compares to a percent equity stake?" asks De Luca. "That could indicate the company is less buttoned up on details and more of a hand-waver - 'Don't worry about that. We'll take care of everyone.' If they're not willing to make sure you understand what you're getting yourself into, there may be other things they're not sharing."
  6. Average employee tenure: "Are people leaving after brief stints?"
  7. Hobbies? What hobbies?: "Ask people on the interviewing team what they do for fun at night and on weekends," suggests De Luca. "If you get blank looks, that means trouble."
  8. Code words: 'Fast-paced environment' isn't necessarily terrible, but probe further to make sure the company knows exactly what they're running towards. Phrases that "imply playing catch-up with competitors or any war metaphors," are always worrying, according to De Luca.
  9. Lack of financial, market or product transparency: "If you join a company that puts a spin on its numbers like, 'We've got 20 large banks as customers' but the reality is all those 'customers' received 95-percent discounts, that's a red flag. Trust but verify."
  10. Lack of interest in who you are as a person. "When the people in the company don't make time to see if you are a good culture fit, that's a pretty big red flag. They should ask you how you like to work and learn how you'd fit in," insists De Luca.
  11. Too big a CEO ego at the top. "No one else matters in those companies."
  12. Your own disinterest in the product. "Passion + skill = happiness," claims De Luca. "If your 'dream job' doesn't combine what you love with what you're good at, the workday will feel endless, even if it's a reasonable eight hours long."

Ask the right questions

Besides staying vigilant for these warning signs, De Luca also insists that the onus is on the candidate to ask the right questions and figure out if the job is a good fit. Just asking, 'What's the company culture like here?' doesn't cut it.

"If you want illuminating answers, you need to ask more probing questions than that," she says. "Some better options include: How does your team make decisions? How do you resolve disagreements? Tell me about something exciting the company accomplished recently. How long did it take, and how many people were involved?"

Have you ever missed a red flag that a company didn't value work-life balance? What was it?