Questionable Advice: “What’s the critical path?”

Dan Golant asked a great question today: “Any advice/reading on how to establish a team’s critical path?”

I repeated back: “establish a critical path?” and he clarified:

Yea, like, you talk about buttoning up your “critical path”, making sure it’s well-monitored etc. I think that the right first step to really improving Observability is establishing what business processes *must* happen, what our “critical paths” are. I’m trying to figure out whether there are particularly good questions to ask that can help us document what these paths are for my team/group in Eng.

“Critical path” is one of those phrases that I think I probably use a lot. Possibly because the very first real job I ever had was when I took a break from college and worked at (“we handle the world’s email”) — and by “work” I mean, “lived in SF for a year when I was 18 and went to a lot of raves and did a lot of drugs with people way cooler than me”. Then I went back to college, the dotcom boom crashed, and the CP CFO and CEO actually went to jail for cooking the books, becoming the only tech execs I am aware of who actually went to jail.

Where was I.

Right, critical path. What I said to Dan is this: “What makes you money?”

Like, if you could only deploy three end-to-end checks that would perform entire operations on your site and ensure they work at all times, what would they be? what would they do? “Submit a payment” is a super common one; another is new user signups.servicelevel

The idea here is to draw up a list of the things that are absolutely worth waking someone up to fix immediately, night or day, rain or shine. That list should be as compact and well-defined as possible. This allows you to be explicit about the fact that anything else can wait til morning, or some other less-demanding service level agreement.

And typically the right place to start on this list is by asking yourselves: “what makes us money?” as a proxy for the real questions, which are: “what actions allow us to survive as a business? What do our customers care the absolute most about? What makes us us?” That’s your critical path.

Someone will usually seize this opportunity to argue that absolutely any deterioration in service is worth paging someone immediately to fix it, day or night. They are wrong, but it’s good to flush these assumptions out and have this argument kindly out in the open.

(Also, this is really a question about service level objectives. So if you’re asking yourself about the critical path, you should probably consider buying Alex Hidalgo’s book on SLOs, and you may want to look into the Honeycomb SLO product, the only one in the industry that actually implements SLOs as the Google SRE book defines them (thanks Liz!) and lets you jump straight from “what are our customers experiencing?” to “WHY are they experiencing it”, without bouncing awkwardly from aggregate metrics to logs and back and just … hoping … the spikes line up according to your visual approximations.)

Questionable Advice: “What’s the critical path?”

How to make boba at home…without ruining any pans, making yourself ill, or ending up with a soggy, blobby mess

Last year I was diagnosed with ADHD, which was a great surprise to me (if no one else). Since then I have been trying to pay attention to things I do that might be, let’s say, outside the norm. One of those things is, apparently, food.

I tend to fixate on one food at a time. When I wake up in the morning, it’s the first and only thing I crave. When I’m hungry, I’m dying for it, and I don’t really experience cravings or desire for other foods, although I will eat them to be polite. The phase tends to last for…six months to two years? and then it shifts to something else.

The target of my appetite has been, at various times in the past: honeycrisp apples with peanut butter (I was DEVASTATED when honeycrisp season ended; other apples weren’t the same), dry cheerios with freeze-dried strawberries, chopped broccoli with sharp cheddar, a cashew chicken dish at a now-defunct Thai restaurant, etc.

One year it was manhattans (makers mark, sweet vermouth and bitters) and I seriously worried I was becoming an alcoholic. 🙈

But since September 19th, 2019, the only thing I have been interested in eating is … boba. Those little brown tapioca balls. I can rattle off to you the top boba places in every city I’ve visited since then (LA has some seriously adventurous ones). And when the world strapped in for quarantine, I was on the verge of panic. What to do??

I finally figured out how to make my own boba. This was NONTRIVIAL. It took the sacrifice of countless pans and far too many nights doubled over with nausea and stomach cramps (read my buying tips, I cannot this stress enough), and months of trial and error. But here is how to get the plump, chewy, slightly sweet boba of your dreams.

(Just the boba. Drinks are up to you. I recommend The Boba Book.)

Buying boba.

Do not buy any boba from China. Do not buy any boba labeled “quick cook”, or boba with instructions that are on the order of 5 minutes. Do not buy any flavored boba. I got violently ill from about half a dozen different brands I ordered randomly off Amazon, all made in China. Some had an odd aftertaste.

Supposedly, the Boba Guys are planning to let us buy the stuff they make domestically in California “soon”. Until then, stick to the stuff that is made of tapioca flour only, and manufactured in Taiwan or The U.S.

Also, the little balls are very fragile and turn to powder in the mail unless they are packed very tightly. This boba, from The Tea Zone is what I buy and recommend buying. Pick up some large diameter straws if you don’t have a stash at home.


You need a big-ass pot of boiling water. The biggest pot you’ve got. I use a big soup pot that holds like 16 or 20 quarts.

Big Ass Pot

If you only have a few quarts of water, you will ruin pans. The tapioca dust turns to gummy that sticks to the sides and bottom and gets baked on like a motherfucker. You want a ratio of SHIT TONS of water to a handful or two of boba.


Fill it up with water to within an inch or two of the top — Bring it to a fast boil, then put your boba in — a cup or two or three, whatever you think you need. Let it boil for 20-25 minutes… only reduce the heat if you have to to keep it from boiling over.

Uncooked boba will have these little white spots in the middle. Once you see only a few of those in a sea of black pearls, turn off the heat. Let it sit in the hot water for another 20-25 minutes.

Spot the uncooked boba

Then take the pot to the sink, pour off the excess water, fill it back up with cold water, swoosh it around to rinse; pour, fill, rinse a couple times til the balls are rinsed and lukewarm. You don’t have to drain them dry-dry; leave a small bit of water in the pan.

Flavoring and eating.

Add some sweetener — I like brown sugar, but honey is good too, or molasses and white sugar — and let the balls soak for another 30 minutes so they absorb the flavor. Now they are ready to eat. They will only keep for about a day, and don’t refrigerate them or they get gross.

**If you want the syrupy consistency of the gourmet boba shops, leave a little extra water in there, add the sugar, then simmer on low and STIR CONSTANTLY for 5-10 minutes or until it gets syrupy. I cannot stress this enough: rinse the boba first, and do not stop stirring, if you enjoy your pans and want to use them again

The easiest possible recipe (besides eating from the pot with a spoon) is, fill a glass 1/3 of the way with boba, add milk, add brown sugar simple syrup to taste. Add a couple ice cubes if you like your boba on the firm side. Also, try adding a little bit of rum and Frangelico for your bedtime boba.


Boba, milk, frangelico
How to make boba at home…without ruining any pans, making yourself ill, or ending up with a soggy, blobby mess

Questionable Advice: Can Engineering Productivity Be Measured?

I follow you on Twitter and read your blog.  I particularly enjoy this post: I’m reaching out looking for some guidance.

I work as an engineering manager for a company whose non-technology leadership insists there has to be a way to measure the individual productivity of a software engineer. I have the opposite belief. I don’t believe you can measure the productivity of “professional” careers, or thought workers (ex: how do measure productivity of a doctor, lawyer, or chemist?).

For software engineering in particular, I feel that metrics can be gamed, don’t tell the whole story, or in some cases, are completely arbitrary. Do you measure individual developer productivity? If so, what do you measure, and why do you feel it’s valuable? If you don’t and share similar feelings as mine, how would you recommend I justify that position to non-technology leadership?

Thanks for your time.

Anonymous Engineering Manager

Dear Anon,

Once upon a time I had a job as a sysadmin, 100% remote, where all work was tracked using RT tasks. I soon realized that the owner didn’t have a lot of independent technical judgment, and his main barometer for the caliber of our contributions was the number of tasks we closed each day.

I became a ticket-closing machine. I’d snap up the quick and easy tasks within seconds. I’d pattern match and close in bulk when I found a solution for a group of tasks. I dove deep into the list of stale tickets looking for ones I could close as “did not respond” or “waiting for response”, especially once I realized there was no penalty for closing the same ticket over and over.

My boss worshiped me. I was bored as fuck. Sigh.

I guess what I’m trying to say is, I am fully in your camp. I don’t think you can measure the “productivity” of a creative professional by assigning metrics to their behaviors or process markers, and I think that attempting to derive or inflict such metrics can inflict a lot of damage.

In fact, I would say that to the extent you can reduce a job to a set of metrics, that job can be automated away. Metrics are for easy problems — discrete, self-contained, well-understood problems. The more challenging and novel a problem, the less reliable these metrics will be.

Your execs should fucking well know this: how would THEY like to be evaluated based on, like, how many emails they send in a day? Do they believe that would be good for the business? Or would they object that they are tasked with the holistic success of the org, and that their roles are too complex to reduce to a set of metrics without context?

This actually makes my blood boil. It is condescending as fuck for leadership to treat engineers like task-crunching interchangeable cogs. It reveals a deep misunderstanding of how sociotechnical systems are developed and sustained (plus authoritarian tendencies, and usually a big dollop of personal insecurity).

But what is the alternative?

In my experience, the “right” answer, i.e. the best way to run consistently high-performing teams, involves some combination of the following:

  • Outcome-based management that practices focusing on impact, plus
  • Team level health metrics, combined with
  • Engineering ladder and regular lightweight reviews, and
  • Managers who are well calibrated across the org, and encouraged to interrogate their own biases openly & with curiosity.

The right way to look at performance is at the team level. Individual engineers don’t own or maintain code; teams do. The team is the irreducible unit of ownership. So you need to incentivize people to think about work and spending their time cooperatively, optimizing for what is best for the team.

Some of the hardest and most impactful engineering work will be all but invisible on any set of individual metrics. You want people to trust that their manager will have their backs and value their contributions appropriately at review time, if they simply act in the team’s best interest. You do not want them to waste time gaming the metrics or courting personal political favor.

This is one of the reasons that managers need to be technical — so they can cultivate their own independent judgment, instead of basing reviews on hearsay. Because some resources (i.e. your budget for individual bonuses) are unfortunately zero-sum, and you are always going to rely on the good judgment of your engineering leaders when it comes to evaluating the relative impact of individual contributions.

This also is why it’s important for leaders to model the act of openly exploring whether they might be biased in some way:

“I would say that Joe’s contribution this quarter had greater impact than Jane’s. But is that really true? Jane did a LOT of mentoring and other “glue” work, which tends to be under-acknowledged as leadership work, so I just want to make sure I am evaluating this fairly … Does anyone else have a perspective on this? What might I be missing?” — a manager keeping themselves honest in calibrations

I do think every team should be tracking the 4 DORA metrics — time elapsed between merge and deploy, frequency of deploy, time to recover from outages, duration of outages — as well as how often someone is paged outside of business hours. These track pretty closely to engineering productivity and efficiency.

But leadership should do its best to be outcome oriented. The harder the problem, the more senior the contributor, the less business anyone has dictating the details of how or why. Make your agreements, then focus on impact.

This is harder on managers, for sure — it’s easier to count the hours someone spends at their desk or how many lines of code they commit than to develop a nuanced understanding of the quality and timbre of an engineer’s contributions to the product, team and the company over time. It is easier to micromanage the details than to negotiate a mutual understanding of what actually matters, commit to doing your part … and then step away, trusting them to fill in the gaps.

But we should expect this; it’s worth it. It is in those gaps where we feel trusted to act that we find joy and autonomy in our labor, where we do our best work as skilled artisans.

p.s. someone just shared this link with me, OF COURSE martin fowler has already said this 

Questionable Advice: Can Engineering Productivity Be Measured?