Things I'd Like to Tell the Younger Me |

Things I'd Like to Tell the Younger Me

Learn how to learn Read the logs Unscrew the black box Learn to read code Keyboard Test editors People API design Books

Learn how to learn

This is by far the most important thing I can teach you: teach yourself how to learn new things. Become used to acquiring knowledge by yourself. Don't rely on others telling you how something works. Learn how to find out this yourself. Then, nothing can stop you.

For Unix commands, this means learning to use the man command (as in manual). If you wonder how the scp command works, type man scp and read it. When I started out with Linux in 1999, I quickly learned the term RTFM ("Read the F**** Manual"). Although, the tone online is nicer these days, this saying is the greatest gift you can choose to embrace: read the manual. On Linux and Mac, they're all available in the correct version corresponding to the machine on which you use them (to search for manuals of interest, you can use man -k <query>).

If the manual doesn't answer your questions, turn to a Google or whatever is the best search engine of the day and make a query like "how do I use the scp unix command?".

For other things, say a Java program that gives you a stacktrace: try to read the stack trace. Even though you don't know Java (say), slowly reading the stack trace will tell you something: a web service something called an XML parser something which called a string buffer something which complained about out of memory something. Ah, what could that be? Think about it. Could it be that someone sent a large XML file to the webservice of the Java app and it ran out of memory?

Read the logs

Logs. Read the logs. This tip alone will set you apart from the bulk of people you'll be working with. Read the logs, all of them, not just the pretty little nice one. Read the logs. Most log entries have timestamps. Use these to narrow down your search for the messages related to the answers you seek.

Figure out what a program does

On Linux, learn to use strace and run it in front of your program. See what files it tries to open and what network connections it attempts to open (strace -f -e open <cmd> and strace -f -e network <cmd>). If you're on Solaris or FreeBSD, learn to do the same using dtrace, or if you're on MacOS learn to use dtruss.

If the source of the app is available, check it out (git is the most popular version control system these days, so a simple git clone <url> will give you access to lots of software that you or your company is using). Check out all the sources of the company's apps that you are in some way interacting with (disk space is cheap). Don't be afraid. Just because it's written in C and you don't understand C, doesn't mean you can get a hunch about parts of what the problem is.

Now, if that doesn't yield the results you're after, then you can ask someone. When you ask them, tell them what you've read and what you've tried. People will be much more motivated in helping you if you can show them that you have made an effort to solve this yourself.

Learn to read other people's code

Everyone's guilty of this: you prefer reading your own code to reading what other's have programmed. It's just so much easier to understand your own logic. It's after all, more logical than what your colleagues have done, right?

For a short time, 2-3 years, I was employed as a consultant providing Java and Linux services to clients. During these few years, I worked on a number of projects, all with large code bases. Lots of legacy (that's the biggest different between coding in university and in the real world, the size of the code base). More than anything, these years taught me (forced me!) to read lots and lots of other people's code.

It's a pity I didn't get this into my head sooner: slow down, try to understand what other people have written, slow down again, try to really understand. Then, you can make adjustments, enhance it or criticise it. But not before you've spent a substantial amount of time trying to understand the code. Don't fall foul to the Not invented Here Syndrome (NIH syndome).


Learn vim

Whatever editor you use as your main editor, learn vim to the point that you're fairly fluent in it. This is the editor that you're guaranteed to find on any platform you'll work on.

Learn one editor really, really well

A text editor is the most important piece of software you'll use as a programmer. It's therefore important that you find one you really like.

Try out all the editors you like and find one you like. Then learn it really, really well. It doesn't matter which one, but pick one which runs on all the major platforms: Windows, Mac and Linux.

My advice would be to Emacs a fair shot (install it, follow the builtin tutorial, then stick with it for 2-3 weeks), it's arguably the most powerful editor in the world, but you must be willing to invest some time learning it.

If you don't like Emacs, I'd recommend you to try out these ones: vim, Sublime, Atom, UltraEdit.

But in any case, the important thing is that you pick one that you like and you can run on all platforms (you will probably use different platforms as you move jobs) and that you become as efficient as possible in this one.

Tell your editors to always add a final new line

It ensures the file looks nice in all contexts.

Emacs and vim do this out of the box.

IntelliJ IDEA: Settings → Editor → General → Ensure line feed at file end on Save

Tell your editors to remove trailing white space

This makes your files look nice and tidy in any context.

For vim, put this in your ~/.vimrc:

function! TrimWhiteSpace()
    let l = line(".")
    let c = col(".")
    call cursor(l, c)
autocmd BufWritePre *.* :call TrimWhiteSpace()

For emacs, add this to your ~/.emacs:

(setq ws-butler-keep-whitespace-before-point nil)

Tell your editors to insert spaces instead of tabs

This makes your files look nice and tidy in any context.

For vim, add this to your ~/.vimrc:

set expandtab

For Emacs, add this to your ~/.emacs:

(setq-default indent-tabs-mode nil)


Remap CAPS LOCK to an extra Ctrl keyboard

You almost never needs CapsLock but you often need Ctrl especially if you're using shortcuts (which you should).

Using CapsLock as Ctrl also reduces the risk of RSI. RSI is something I didn't care about before I reached my middle 30s. I wish someone had told me to use CapsLock from the early days on. It would have saved me a lot of pain.

Learn to touch type

Touch typing isn't important at all. Most of the time, you spend time thinking, not writing code. Besides the IDE makes writing code super easy! 😠

Don't be offended by this, but after working for 15+ years, I'd say with very few exceptions, the best coders are the ones that touch type (or write fast on the keyboard by some self invented approach). This probably upsets a lot of people, but it's my honest opinion. The good news is that everyone can learn to touch type.

Text is the way of life as a programmer. Emails, chats, commit messages, wiki pages, documents and presentations. The written communication far outweighs the oral communication you do. Most jobs today are even distributed, with colleagues and stake holders in multiple countries and time zones. Limiting your communication to what you get to do around the coffee machine and your co worker sitting beside you and video conferences with the other colleagues just doesn't cut it.

If you touch type, communicating and documenting will not be a pain for you. If you don't touch type, you will tend to avoid written communication and documentation tasks or you will reduce it. You will write more cryptic commit messages (writing detailed messages costs too much if you type with four fingers), you will hesitate to create a wiki page to help out fellow coders on how to solve a tough problem you have just overcome and so on.

If you're not convinced, reads this blog post by Steve Yegge: Programming's Dirtiest Little Secret


The ones that claim they know everything

Unless you're talking to someone who is a true leader in his/her field, like Linus Thorvalds talking about operating systems or Kevin Mitnick on IT security, there are seldom absolute truths. If someone proclaims in front of everyoneq trying to solve a strange problem of a software client dropping packages from one cloud vendor (but all other downloads are fine):

"This cannot be, TCP timestamps prevent this from happening"

I might be well intended, but often simple, absolute truths, presented in an assertive manner, is a statement of less quality. I've learned to appreciate people saying:

"In my option ..."

"To my knowledge ..."

"As far as I know,"

"On the projects I've worked on in the past .."

The thing is, the more you know, the more you know that you don't know. The best programmers I've worked with are the ones that have realised this and therefore presents their opinions in this light. These are the persons I listen the most to. The ones that would say:

"This seems extremely unlikely, normally, TCP timestamps should prevent this from happening. It could of course be some factor here that I am not aware of."

And in case you were wondering: of course it turned out that TCP timestamps can indeed be turned off, which was why a client had problems downloading data from Amazon's S3, but not from any other server.

Fellow developers

Spotting a good developer

Dare to say "I don't know"

The best developers I've worked with, are the ones that admit when they don't know something. Daring to say "I don't know" among his/her peers is often a sign of technical excellence.

Dare to ask "How does that work?"

Again, the best people I've worked with, dare to reveal that they don't know everything when discussing with a group of developers. Others fake it, just nod or don't say anything.


The Pragmatic Programmer: From Journeyman to Master , is without a doubt the best programming book I've ever read

Unix Power Tool is a treasure chest for anyone working with Unix systems. Linux, OSX, Solaris, IRX, FreeBSD, NetBSD, OpenBSD users are all catered for alike. This is a true gem of a book. It's big and heavy, yet it can be enjoyed in small sips. Just pick it up, flip through the pages and read 2-3 of them. You'll turn away wiser than when you opened it!

Effective Java If I were to only read one Java book in my life, it should be this on. This excellent book from Joshua Block focuses on core Java programming and can be read by any developer, regardless of what platform or frameworks you're using.


Learn a few languages

Good programmers are proficient in a good few languages. You should be too. Start out by learning one scripting language, one object oriented language and one functional language.

API design

Start off by writing the client code, then implement your API. This is in some circles advocated through TDD (test driven development), but you should do this regardless of TDDing (which is of course, a good idea).

By writing the client code, I mean, write the code the way you as a user of the great new API you're about to create, would like to write. E.g. say you want to build a ice cream vending machine backend. Before implementing all of that, start by writing the client code that the clients talking to the vending machine will use, e.g.:

IceCream iceCream = vendingMachine.fillUp(new Cone(Size.BIG, 2));

Once you're satisfied with the client code, then start implementing the actual vending machine, the REST calls, the database layer, the business logic.

Too few developers do this. Therefore, their APIs and systems become extremely complex to use. Good APIs to draw inspiration from are the XOM XML library for Java and the Requests HTTP library for Python. The APIs "just work" the way you'd expect. At least, the way I would expect 😉

If you follow this principle and also puts your client code in a unit test, you'll not only get a nice test that you can run automatically whenever changing something in your program, but you also magically ensure that your code becomes loosely coupled and easier to maintain (trust me on this).

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