Crafting Interpreters

I’ve been working my way through Crafting Interpreters by Robert Nystrom for the past few days. It’s an excellent book about creating your own programming language.

I was already familiar with Nystrom’s previous book Game Programming Patterns. A great book on design patterns, even if you’re not a game programmer.

Crafting Interpreters covers a new object-oriented scripting language called Lox. You’ll first implement a tree-walk interpreter in Java and then create a bytecode virtual machine in C.

I probably won’t ever directly use these skills in my day job, but gaining a deeper understanding of interpreters and virtual machines can’t hurt. Especially considering I split my time between the Ruby interpreter and Java VM.

Almost as interesting as the book itself is the way he wrote it using a combination of Markdown for prose and hand-drawn diagrams. More details are in his blog post Crafting “Crafting Interpreters”.

If the book sounds interesting to you, you can read it online for free at the link above. After reading the first few chapters onscreen, I bought a print copy. I like having the book open on my desk while writing code.

The Matrix Resurrections

Oh my god. I realize this is two Matrix posts in a row, but this trailer looks amazing!

In theaters and HBO Max on December 22. That makes me even happier. I really want to see this, but I’m still not ready to step back into a theater. I honestly may never be.

Matrix Time

When I was a younger there was a phone number you could call where a recording would tell you the current time and temperature. I never really thought too much about that. It was obviously an early computer generated voice filling in the time and temperature.

Now, there’s a website for the upcoming Matrix movie that incorporates your local time the right way.

The Choice Is Yours

Thanks to a post on Reddit, you can see how it was done. There are 1,440 copies of each trailer, one for each minute of the day. A bit of clever code picks the correct video to play based on the local time in your browser.

Not rocket science, but it did get people talking.

Bringing Back WebRings?

If you can make it past the over abundance of ads (Reader View is your friend), this is an interesting article about the Internet days of old.

What these rebellious programmers are building goes by many names—indieweb, yesterweb, folk internet—and relies on simple design choices, often borrowing elements from the 1980s and 1990s.

Tech Workers Rebel Against A Lame-Ass Internet By Bringing Back ‘Geocities-Style’ WebRings

I don’t think this is exactly the modern definition of indieweb. See for more info. But I guess this is close. I like the terms yesterweb and folk Internet for this style of website.

I had a webring on one of my old web pages, and I had a Geocities site back in the day, but I don’t see myself jumping on Neocities any time soon. I understand the nostalgia, for sure. I guess I could create a page with a few of those “under construction” gifs and call it done.

Remember the time before content was served via algorithms designed to exchange attention for dollars? At the end of the day, this is just another example of a group of old folks like me longing for the web that was.

The Internet Is Dead

This is probably the least-crazy conspiracy theory I’ve read about lately. In some ways i guess it’s true. The “real” Internet is definitely not what it once was.

Let me explain. Dead-internet theory suggests that the internet has been almost entirely taken over by artificial intelligence. Like lots of other online conspiracy theories, the audience for this one is growing because of discussion led by a mix of true believers, sarcastic trolls, and idly curious lovers of chitchat.

Maybe You Missed It, but the Internet ‘Died’ Five Years Ago

Most people think of social networks when they think of “The Internet.” It’s well known that much of what ones sees there is created by only a few people and served to the masses via a clever algorithm.

Want everyone to see your content? Trick the algorithm into thinking your latest work is very engaging. All it takes is one “influencer,” a few hundred bots, or a paid promotion and the world will know your name.

Of course this conspiracy theory goes one step further. (Don’t they always?) It claims that most of the content you see online is actually created by an artificial intelligence before being propagated by bots.

More great writing from The Atlantic.


Happy New Year! So much has changed for me over the past few months, I’m really not sure where to start.

Last year I wrote a series of blog posts about landing a new job as a programmer. I covered setting up your LinkedIn and Github profiles, updating your resume, writing portfolio code, etc. I even interviewed a few friends about their experiences. I had plans to turn this into a book. (I still think this will happen.) This series of posts should have made it obvious to anyone what was on my mind.

I’ve never really been a fan of online advertising (is anyone really?), but around the beginning of last year I had grown completely disillusioned with it. I read so many articles and listened to so many podcasts about just how bad things were getting. As a result of this, I was honestly doing a terrible job at work. I kept telling myself that it was just a job. The people were great, the pay was good. But in the end, I just couldn’t do it.

I signed up for a couple of the tech job matching services and things basically exploded. I interviewed with around 25 different companies. I started with a single idea: I want to work on a product that people pay for with money, not attention or engagement. As I talked to more companies, another idea started to seem possible: I want to work full-time remote. Those two requests narrowed the field and in the end I accepted a position as a Software Engineer at Braintree.

The new job is great. I’m back to writing code every day. I’m part of a smart, helpful team. I’m learning new things all the time. I pair program every day. I’m doing more backend / infrastructure work than ever before. In addition to Ruby, I’m also writing Java (and actually enjoying it) and working with things like Docker, Puppet, and Kubernetes. And the best part is, my commute has gone from around 2 hours per day round trip to however long it takes me to walk from the bedroom to the office.

Code Kata

Over the course of interviewing for a coding job, you’ll be required to prove that you actually know how to write code. This is usually by solving a problem of some kind. This might be a take-home challenge, a pair-programming exercise, or even (shudder) coding on a whiteboard. Obviously, you’ll want to practice these kinds of problems.

Many of the problems used in interviews can be found online in the form of a code kata. The name code kata comes from the kata in martial arts. In martial arts this involves practicing a set of moves repeatedly until they become like a reflex. Here’s the definition of a code kata on Wikipedia:

an exercise in programming which helps programmers hone their skills through practice and repetition.

I’m not really happy with that definition. To me, a code kata is different in that you shouldn’t repeat the same problem. Instead, solve a variety of challenges to build your problem-solving and coding skills. Of course, if you aren’t happy with a solution, refactor it or even start over, but I feel like the biggest gain comes from solving a many different problems.


So, where do you find these problems? Here are a few websites I’ve used in the past:

Project Euler has hundreds of challenging mathematical and computer programming problems. If you work your way through this list, you’ll be ready for anything. Many of these will be too difficult for a beginning programmer.

CodeKata is a site by PragDave (aka Dave Thomas of the Pragmatic Programmers). According to Wikipedia, Dave Thomas was probably the first person to use the term code kata. This site has a collection of 21 challenges.

Exercism has a collection of practice problems in over 30 different programming languages. If you only visit one site on this list, start here. After you submit your solution, you can see other users solutions and give and receive feedback.


The sites above involve solving a problem of some kind, but The Gilded Rose kata is all about refactoring. You’re given a program and asked to add a feature. Unfortunately, the program is poorly written and has no tests. Rather than just add the new feature, you’re expected to also clean up the program.

After you try the kata on your own, check out the talk All the Little Things by Sandi Metz at RailsConf 2014. Sandi Metz is the author of the highly recommended book Practical Object-Oriented Design in Ruby and a great speaker. If you’re a Ruby developer, you should watch all of her talks (assuming you haven’t already seen them).

What is your experience with practice problems? Did I miss a great code kata resource? Do you think this is all a waste of time? I’d love to hear your thoughts about coding challenges such as these.

Your Resume

Now that your LinkedIn profile is looking good, use the information it contains to write your resume. A resume is not strictly required since most companies are happy with just a LinkedIn profile, but it never hurts to have one.

There are many fancy resume templates available online, but I recommend something clean and simple. I follow a format similar to the way my LinkedIn is setup.


First, put your name at the top in large text. I used Microsoft Word’s Title style, a 28-point font. Under your name, put your LinkedIn address and contact information. Include at least your email address and phone number. Finally, finish off the first section with your summary statement. Here’s mine:

Experienced Engineering Manager and Software Engineer with a BS in Computer Science. Author of Rails Crash Course. Speaker, community organizer, teacher, mentor, blogger.


Add a heading, then list your experience. Put your job title in bold, followed by the company name and dates of employment. For your most recent roles, give 3-5 bullet points with the things you do as part of your job. Also include a list of technologies used in case someone is just scanning for keywords.

If you don’t have a lot of professional experience, include volunteer work or personal / freelance projects here. This is especially important if you’re seeking your first job as a software engineer. If you’re looking for a coding job, but your only experience is driving for Uber, then your resume isn’t really helping.

If you have a lot of experience, list fewer and fewer details for older jobs. For past positions maybe only list technologies used. For jobs that aren’t relevant to the position you’re currently seeking, only list the title, company, and dates. You might even leave these off assuming it wouldn’t look like a gap in employment.


Finish up your resume with information about your education. List your college degree if you have one. List the bootcamp you attended and/or any online classes you’ve completed.

If you haven’t done any of these things, just leave this section off. I would avoid doing something clever like “graduate of the school of life.” Some hiring managers might think that’s cute, but others will probably discard your resume.


I make no mention of skills other than as part of my employment history. I don’t see the need for a big block of skills. Anyone can type a list of programming languages, show me what you really know by listing some experience.

I also don’t mention references. Everyone knows you’ll provide references on request, so why bother taking up space on your resume? Many companies don’t even ask for references anymore.

My resume is just under two pages long. Many people will tell you that your resume should fit on a single page. I don’t see how that’s possible for someone with a few different jobs and some education. List everything you need and don’t worry about the length.

Finally, export your resume as a PDF. I don’t usually print my resume unless I’m going for an in-person interview. In that case, I print a few copies and stash them in my bag in case someone asks for it. So far no one has ever asked for a hard copy, but better safe than sorry.

Your LinkedIn Profile

The first thing I look at when someone applies for an engineering job is their LinkedIn profile. Even before I look at their resume. To me, there are two big benefits to going straight to LinkedIn:

  1. I can easily see how we’re connected. Do we know people in common? Maybe you used to work somewhere I used to work. Maybe you met someone I know in a user group. This connection could tell me what you’re really capable of, even if you aren’t good at selling yourself.
  2. It’s in a standard format. You can customize your profile page a little, but for the most part they all look the same. I know where to find your experience and education without thinking. It’s easy to quickly scan the page and get a sense of where you’ve been.


The first section is called the intro. As I said in my post about your GitHub profile, put a current, recognizable picture of yourself here. Next, add a headline consisting of your current job title and employer.

If you aren’t currently working, or aren’t working in technology, I would be a little more creative here. Are you doing any freelance work, writing, or teaching? If nothing else, write something like “Aspiring Software Engineer.”

Finally, add your summary. This is basically your elevator pitch. Think of one or two sentences that quickly tell an employer what you can do.

Experience & Education

The experience section can be a challenge for someone seeking their first coding job. How can you list experience when you don’t have any? Obviously, you can’t. If you’re currently working outside of the technology world, you should list your job. Even if it’s barista at Starbucks.

Once you land your first technical job remove your earlier experience, unless you can make a compelling case for how it might make you more attractive to a future employer. For example, if you had management experience in a previous, non-technical job, you might want to keep that on your profile.

Include a few sentences or bullet points describing what you accomplished at each of your previous jobs. If you aren’t sure what to write or how to word your accomplishments, try looking at job postings for similar jobs. Recruiters work hard getting the wording just right on their postings. Reuse their work.

You can also add volunteer experience in this section. Many organizations need help building or updating their web site. You can also volunteer to teach coding or other skills in your free time. is always looking for programmers to volunteer to teach coding to kids in the classroom.

The education section should be straight-forward. If you have a college degree, list it here along with your major field of study. Similarly, if you attended a coding bootcamp, list it here. You can also include relevant online courses such as those at Udemy,Coursera, or freeCodeCamp.

Skills & Endorsements

List skills such as programming languages and frameworks, industry knowledge, and interpersonal skills in this section. If you have demonstrated these skills to other people, ask them to endorse you. An endorsement from someone tells me that you truly have the listed skill.


Personal recommendations can be hard to get. Give recommendations and hope that the recipient will recommend you in turn. I would also directly ask for recommendations from managers and coworkers. Just be aware that asking for a recommendation on LinkedIn can be interpreted as a sign that you’re looking for a new job.


Use the accomplishments section to highlight things like publications you’ve written, awards you’ve earned, or special projects you’ve completed. This can be a great way to fill out your profile if you don’t have a lot of experience yet. Also, include any foreign languages you speak here.