The more I work with deep inheritance hierarchies, the more I wonder if inheritance is actually a good idea. If you’re looking to avoid the trouble overusing inheritance can get you into, this article has some handy tips: Inheritance is evil. Stop using it.
You might have guessed from my extremely wordy blogposts that I like writing as well as programming :) Aside from having a personal interest in writing, I think there are some really useful parallels between writing and programming.
Let’s talk about one of them: separating writing and editing. This is a pretty common piece of writing advice, I’ve seen it all over the internet.
More specifically, what separating writing and editing means is that when you start a piece of writing, you don’t edit, you just get your ideas out onto the page. Only after you have a complete first draft, whether that’s a blog post or a novel, do you edit it. Editing can be as simple as fixing typos or as in-depth as moving whole chapters around.
Why is editing while you write such a bad idea? We’ve all written essays for school and edited while we wrote and we survived, right? Well, we did, but we also put in way more effort than we had to. It is totally possible to edit while you write and turn out a perfectly good school assignment, or even a professional article or book, it’s just way more work than it has to be to do it that way. It takes for-freaking-ever too and we’ve all got other things to do :)
Separating writing and editing makes you way faster. Yes it works better if you have a little space between the writing (drafting/outlining) and editing steps, but you’ll spend less time altogether on a piece of writing if you put a day or two between those steps.
But why is that? Writing isn’t that hard, and editing isn’t that hard (to be fair, I’m saying that as someone who has always had an easy time with writing), so what’s the problem?
Part of it is that people just suck at multitasking. Fiddling with your words is a very different task from getting them down in the first place, but I think is the real issue is that editing and writing at the same time is mixing two steps that need to be done one after the other.
It doesn’t actually make sense to worry about how you’re saying it before you’re done sorting out what you want to say in the first place. That’s just going to make a mess.
Okay great, how does this relate to programming?
Programming is in many ways a very similar process to writing. You need to know what you want to do before you can figure out how exactly to do it. Programming is certainly more rigid, with writing you can still make yourself understood with a misspelled grammatical trainwreck, but it’s not so very different either. You can start a piece of writing and know just what you want to say and then discover it just sucks and you have to scrap it and start over.
What you want to do with a program can be more tightly constrained by what’s feasible given the existing system/libraries available/limitations of the language you’re using, but in some ways that makes it easier because there’s no debate over whether your program works or not, you can just run it and find out.
When you’re writing code it’s very simple to separate writing from editing: write pseudocode first. Figure out what you want to accomplish (yes that’s a big enough problem for many books on its own, but that’s another blog post) first, then break it down into simple steps, then start implementing it after you know what you want to do. It may turn out that there’s a technical reason your original plan won’t work, but you can still iterate on that and make a new plan before trying to implement that one.
If you find yourself stuck on a problem, you might be trying to do too many things at once. Try separating what you want to accomplish from how you want to do it.
This particular question is about learning a new codebase at work, but I think there’s plenty of stuff here that would carryover to learning the codebase of an opensource project you want to contribute to.
When you want to learn a new codebase, the very first thing you need to do is get it to build on your machine. Deliberately breaking things is an extremely useful tool when you want to understand a codebase, if you can’t even build the app you have no chance of figuring out if you broke it or not.
At work there should be another dev around who can sit down with you and help you get everything set up so you can compile, if you’re working on an opensource project you’re going to have to rely on docs, maybe a community chat like slack, gitter, etc, and sheer stubbornness.
Next you need to be able to run it or at least run the tests (if there are tests). This can be a lot more work than just getting the app to compile. For example, the app I work on at my own job compiles really easily but it won’t run unless you have all the environment variables set up correctly and the database and cache and everything installed. You’re probably going to want that coworker’s help here too. If you’re lucky your company has docs you can read and if you’re very lucky they’re even up to date, but at most places I’ve worked the development environment setup process was never written down, only passed down orally.
Quick aside: I’ve said this before, but if your company doesn’t have any docs, write them! Seriously, you’ll make things so much easier for the next dev, who might even be you. If your computer dies on you and you need to get setup again in a hurry, you’re going to be really grateful if you can follow the docs instead of desperately trying to remember how to do that one tricky bit.
Depending on how your app works you may also need help creating an account for yourself so you can actually log in and use it. Once you can build, run, and log in (if you need to), you can really start digging into the code.
What makes the most sense to me is starting from the UI and working my way in from there. It also really helps me to have a goal, like a bug to fix or a small feature to add. I get lost if I just sort of wander around a codebase trying to figure out how everything fits together, having a goal helps me focus.
It’s also totally okay to ask another dev for a quick overview of the app, having a bit of context can make it a lot easier to figure out how everything fits together. Customer documentation can be really helpful here. Sure, it won’t tell you which controller handles the data for the user details page, but it will tell you how to get there and what you can do there.
Eventually you’ve got to get in there and start looking around, though. I poke around the UI until I find a screen that looks like it could be related to the thing I want to do, then I copy some text from that screen (ideally something that looks distinctive) and search for it in the code. Most of the time this is helpful but sometimes the text you thought was distinctive really isn’t, you may have to search for a few different things before you find something that gets you useful results.
If the app is a webapp it often helps to open up the network tab in your browser dev tools and look at the calls the frontend makes to the server. If you’re not sure exactly which endpoint is actually getting called this can clear things right up. Don’t be afraid to add more logging either, just try to remember to clean it up when you’re done :) I do that all the time when I’m trying to figure out exactly what my app is up to. If you want to get fancy you may even be able to attach a debugger to your running application and step through the code one statement at a time. I have this irrational dislike of doing that (I find stepping through the code tedious and would rather just throw in another System.out.println), but if it works for you, great!
Once you find the right server calls it should be fairly simple to trace your way back through the code all the way to the database (or other data store) if you need to. I mostly work in Eclipse, so I’m working from the assumption I have good IDE support and can easily navigate the project once I decide where to start. If you aren’t using an IDE that makes it really easy to find the definition of a class or method, you’re just going to have to do a lot of searching.
IDEs can only do so much for you, though. When I’m trying to figure out a complicated part of the code I’ll sort of draw myself a map so I don’t get lost. That is, I’ll write down, either on paper or in a text file, exactly what calls the method I’m looking at, and what calls those methods, and what calls those methods until I’m clear on how everything fits together and where exactly that one bad parameter came from.
Like I said earlier, breaking stuff on purpose can be a great way to verify that you understand how the pieces fit together. Once you think you know where the problem is / where you should add your new feature, try commenting out the body of a method and seeing if things break the way you expect. If they do, great! If they don’t, hey at least you found out sooner rather than later that you were wrong about how it works. Another good way to break things is to give them bad data. I do that when I want to know if my request is even making it to the part of the code I’m interested in – if it doesn’t break the way I expected then I know I’m wrong about what the code is actually doing.
If one screen or endpoint or whatever just doesn’t make any sense to you, try another one! You may just need to see more of the app before things start coming together, or you may have just had the bad luck to stumble across an especially tricky part of the app. Keep trying, and ask for help if you need it, you’ll get it.
Speaking of asking for help: most developers hate doing it, but it really is okay to ask for help if you get stuck. Especially if you’re a junior, it takes practice to get good at finding your way around new codebases. Five minutes of explanation by someone who knows the code could save you hours of confusion and frustration. The faster you get up to speed on that new codebase, the more help you’ll be to your coworkers, so it’s actually in their best interests to interrupt them (after trying to figure it out on your own, of course) to ask for help.
One last tip: it takes months, literally multiple months, to really be productive at a new development job. If you feel stupid and useless, that’s a) not true, and b) totally normal. You would never tell a new hire that they’re an idiot for not instantly figuring out a new codebase, so try to be that nice to yourself, okay?
Why tomcat? Because it’s open source, I’ve used it before, and honestly it was the first thing that came to mind :) Oh, and for anyone reading this who hasn’t spent a ton of time writing Java webapps, a servlet container is a kind of webserver that provides a nice little home for your servlets, which are little Java programs that take http requests and give back http responses.
Tomcat does indeed have a main method, it starts on line 457 in Bootstrap.java. There’s even a helpful comment that says “Main method and entry point when starting Tomcat via the provided scripts.”
Which is all well and good, but that makes for a pretty boring blog post :) So let’s talk about how I hunted down that main method. I could have just searched for “static void main” in the Tomcat github repo, but a) I just tried that and it wasn’t actually super helpful, and b) what I really wanted to know was what happens when you start Tomcat.
It’s been a while since I used Tomcat so I looked at the docs first. In the readme on the github project there’s a link to RUNNING.txt, which looks promising.
So I skim through that (there’s a bunch of stuff about installing tomcat and setting up environment variables that I don’t care about right now, I just want to know what the startup script is called) and eventually find the section about starting tomcat. In there it says that the startup script for linux users like me is $CATALINA_HOME/bin/startup.sh (there’s a .bat file for windows users too if you’re curious).
Okay great what’s in startup.sh? (also thankyou github for having a file finder!) It turns out there’s not a ton in there and I don’t understand most of it, but at the end of that file is “exec“$PRGDIR“/“$EXECUTABLE“ start “$@“”, which I think I can assume executes a thing :) Also a little earlier in the file is EXECUTABLE=catalina.sh.
Given that, it looks like startup.sh does some pre-setup setup and then catalina.sh actually starts the server (if there’s a 3rd level of startup scripts I’m going to be really sad). There’s a lot more going on in catalina.sh that I skimmed through, but I eventually started seeing a lot of evalexec“\”$_RUNJAVA\”“ [many more vars] org.apache.catalina.startup.Bootstrap “$@“ start. That $_RUNJAVA thing sounds like it might, you know, run Java :) That probably means that the startup class is org.apache.catalina.startup.Bootstrap, let’s go see if there’s anything interesting in there. And what do you know there’s a main method. It took some scrolling to get there but we made it eventually!
You may or may not care about how Tomcat (or any other given application) works, but what I hope is interesting is that everything an application does is understandable. Nothing the computer does is magic, it’s all knowable.
Today’s code smell is temporary fields. Like with all code smells, sometimes these aren’t a problem at all. For example, it’s pretty normal to have a user object with a bunch of optional fields. Sometimes you have users who just start out with a username and a password and fill in their profiles later and sometimes you have fields for stuff like social media accounts that only some users will ever fill in, but sometimes fields that only sometimes have a value are a problem.
One of the ways people try to fix the problem of a long parameter list is to make some of those parameters into fields and then set them later if they need to. Unfortunately that’s not really any better because it just hides some of the confusion under the rug instead of actually getting rid of it. Instead of it at least being obvious you have too many parameters, now you have a bunch of fields that may or may not get used depending on what the object is up to and you have to go hunting to figure out what’s going on.
Since professional programmers read code much more often than we write it, it’s a huge waste of time to have to go on an exploratory mission every time you need to understand that code again. If you do end up needing to update that code, best of luck figuring out which fields are important and whether your refactor / bug fix / new feature broke anything.
I had a heck of a time finding a code example for this code smell but fortunately so did Mark Seemann, who was frustrated enough by that to write not just an example of the smell but of how to refactor it too.
If you find this smell in your code, what do you do about it?
Pulling out the temporary bits into their own object and just using that is a good option (if that works for your code, of course). Isolating the fiddly bit makes the rest of the object cleaner and makes it clearer what the fiddly bit is up to. You can also add a null object (a special object where you put whatever defaults you use when one of your temporary fields is null). That way your normal processing code can be clean and simple instead of littered with null checks. Sometimes that just makes things more complicated, so it’s a bit of a judgement call.
If you’re having trouble figuring out what an object even does because most of its fields are null most of the time, see if some refactoring helps. You can always put it back the way it was if it’s worse afterwards :)
First of all, software development is a team sport. Sure, side projects and prototypes can be built by individuals, but the vast, vast majority of business software is built by teams, which means that communication is everything.
Are you going to go out of your way to communicate with the arrogant jerk on your team? No you are not. Nobody does that. Even if you really need to you’re going to put it off as long as possible. Yes that’s not ideal, and you can make the argument that it’s illogical, but let’s be real, humans have emotions and we don’t like dealing with jerks. To have good communication on your team you have to make it as painless as possible.
Arrogance is also a literal blocker to ideas. Arrogant jerks make people scared to speak up about ideas they aren’t completely sure about because they don’t want to make themselves targets. The bigger the jerk the more scared people get until nobody speaks up at all. Jerks also make people scared to try things – if a jerk is looking for any excuse to shit on you of course you’re not going to try anything that could possibly fail. With a bad enough jerk, nobody on the team grows as a programmer because they never try anything they haven’t done before.
Jerks also make your team avoid code reviews, at least if the jerk is involved. Nobody wants to hear that everything they built is terrible and the jerk could do it 1000 times better even if there are a couple of valid needles in the haystack of outright meanness. You can be sure no one will volunteer to review the jerk’s code either, which means standards start slipping, bugs may get into prod – not because code reviews are specifically about finding bugs but because code reviews are great for catching “this is really complicated and I’m having trouble following it, can you pull it apart and simplify it?” and that prevents bugs – and if somebody needs to change the jerk’s code nobody will know where to start because nobody reviewed their code.
And a jerk’s code often really needs reviewing. In my (thankfully limited) experience, jerks who think they’re smarter than everyone else write overly complicated code that no one else can follow to prove how extraordinarily clever they are. This has been known to backfire when it turns out that not even the oh-so-clever jerk can follow that code. Even if anyone is willing to review a jerk’s code, it’s not likely to improve that code because jerks rarely take feedback well. If they did, they’d stop being jerks!
Yet another way jerks harm your product is by ramming their ideas though by making every disagreement or discussion a huge fight. Eventually the rest of the team will get tired of having that fight over and over and let the jerk have their way, if only so they can stop talking about it. Just like with avoiding communicating with a jerk, you can argue that it’s short-sighted to prioritize avoiding a fight right now over dealing with the long term fallout of bad decisions, but you’ll get farther by expecting people to act like people than you will by expecting them to act like emotionless robots.
Finally, why should any non-jerk on your team bother to do their best when you let a jerk get away with writing bad code, refusing to listen to anyone else’s ideas, and making everyone around them feel terrible? If you won’t avoid hiring a jerk for any other reason, do it because all of your devs who can get a better job will do that just so they don’t have to spend all day at work with a jerk. Life is too short to work with jerks!
So last week I talked about how you can’t know if code is good or bad without knowing the context, what you’re actually trying to accomplish with that code, what was most important when it was written (priorities change, that doesn’t mean that the way the code was written at the time wasn’t perfectly reasonable for the context it was written in).
But there’s more to context than that! You also can’t know whether your code is any good in isolation. In other words, unit tests are not enough and can never tell you whether your code actually works. No seriously, they can’t. That’s because your code doesn’t work unless the whole app works, and the only way you can tell whether the whole app works is with end-to-end testing.
It’s great if all the pieces work according to your unit tests, I’m not knocking those, but they can’t tell you the whole story. Only integration tests can do that.
If you haven’t run into integration issues yet, just wait, it’ll happen :) Maybe your controller doesn’t validate user input quite the same way as the service that handles business logic does. Maybe one layer tolerates nulls and another one flips out and throws NPEs. Maybe the front-end and the back-end disagree just slightly on the format of the JSON that gets passed back and forth. Maybe one layer doesn’t return the exact error codes another layer/object/service was expecting.
Hell, maybe everything is great except for some missing assets on the frontend. That’s not covered by an integration test but it’s not really unit test territory either. Some stuff just has to be looked at by a human. Yes, it’s possible to automate frontend testing but if your UI changes very often at all then it may not be worth the trouble of reworking your tests every time it changes. Plus computers are kind of terrible at stuff like “this text doesn’t line up nicely with this text box,” so you’re going to need a human to look at your UI anyway.
It would be great if unit tests were all you need, and if you have really comprehensive unit tests you will catch most of your problems, but in the real world things break not just within components but between them. An application isn’t just a collection of models, views, and controllers (assuming you went with a MVC architecture), it’s also the interactions between those components. If you aren’t testing those interactions, you just aren’t testing enough.
Of course, even integration tests have their limits. I once broke production by changing a part of the system that I thought was unrelated to the part that broke. It was not :( (also cache invalidation is the worst). Integration tests are great for things you know are related, but sometimes you just need a human to click around in the app and notice that when you change setting A, feature B that seems unrelated doesn’t see the update.
If you possibly can, learn from my mistakes: it doesn’t work unless it all works together.
That one didn’t go at all the way I thought from the title. It turns out the business priorities actually did make sense (the business had this wild idea that queries, even especially complicated ones, should take less than 4 hours to run) and the programmer was being unreasonably rigid in following “best practices”.
But weirdly, one of the answers said that both parties were wrong – that the programmer shouldn’t have been so attached to having nice looking code and the manager shouldn’t have insisted on using an anti-pattern. What? The anti-pattern (using raw SQL instead of the ORM) improved performance by multiple orders of magnitude! If performance matters at all, you cannot possibly tell me that massively improving performance was the wrong thing to do.
Okay, there is some nuance there :) If your ORM performs that badly it’s likely not configured right for your situation, so it might be better in the long term to fix your config than to keep writing custom SQL for every query that’s the least bit complicated. On the other hand, if you don’t have an expert handy who can tune your ORM config, it might be easier to ditch it, at least for the more complicated queries, and just write some SQL. Or hey, how about a compromise? Use a stored procedure, that’s what they’re for! If it’s a query you run a lot, it might even make sense to make a view for it.
No matter what you end up doing, it’s still not wrong to use a supposed “anti-pattern” if you have a good reason to do it. It’s the context that makes something a bad idea, even the best idea can turn bad if you use it the wrong way. The only way to know whether your “anti-pattern” is actually a bad idea for your particular situation is…. to look at your particular situation! You can’t just say something is an anti-pattern without knowing what the person using that anti-pattern is trying to accomplish.
Let’s look at another datebasey example. It’s generally considered a bad idea to denormalize your database, every database design course will tell you so. Normalizing your database ensures all of your data is always right by isolating everything that can change independently. Since you don’t usually bother to keep data at all if you don’t care if it’s all accurate, you almost always want your data nicely normalized.
But sometimes correctness isn’t the absolute most important thing. Let’s take browser or mobile games, for instance. If your game takes too long to load, your players will just go do something else and they might not ever come back. It’s much more important to be fast than it is to be perfect if you want to make money on a game like that. And if something does go wrong and a player gets mad because their data didn’t get saved correctly, you can just give them game currency until they’re happy again.
In a situation where performance is more important than correctness, normalization is the anti-pattern. Like I said, it’s all about context!
To be clear, there are some things that are just a terrible idea no matter what you’re doing. I don’t care how clever you think you are, your variable names need to make sense. And no matter how well it performs, if your system is so confusing than no one can make updates, then it’s a bad system. But for the most part whether or not something is an anti-pattern is about what you’re trying to accomplish more than it’s about the “anti-pattern” itself.
Everybody likes code that makes sense to them, and everybody likes to feel like they’re doing things the right way, but rigidly following “best practices” just isn’t good enough. If it doesn’t help you achieve your greater goals for your application (ie not just gold-plating your code, but providing value to your users or customers), it’s just not a good idea no matter how many experts call it a best practice.
And yes, that means you can’t know if your code is good or bad without knowing exactly what you’re trying to do. Welcome to professional programming!
It sounds obvious, but I have wasted so much time debugging problems that turned out to be something ridiculously simple like my browser cache being outdated, having forgotten to deploy my code, having made my updates in my local database instead of the staging database, etc, etc. Better developers are more productive, and you know what instantly makes a person more productive? Wasting less time!
Double checking extremely simple obvious things can save you massive amounts of time. Like I said earlier, a little self-doubt is good for you. If you can’t ever doubt yourself at all, you’re going to waste a lot of time on silly mistakes you could have just double-checked.
This can be really really hard to remember as a dev, so don’t feel bad if you mess it up sometimes. My best guess is that’s a side effect of working with complicated problems all the time, so we assume the problem has to be more complicated than just having deployed the wrong code like a dope.
Another great way to keep things simple is to build the simplest possible solution for your problem. This is such a common problem that we have an acronym for it already: YAGNI (you ain’t gonna need it). Before you write more code ask yourself “Do I actually need this?” Protip: if you actually need the thing it will be obvious. If you don’t actually need it, don’t build it. Yes, things should be somewhat flexible, but there’s a limit.
Names are a great clue to whether you’ve built something so flexible that all it’s really doing is adding complexity. If you can’t guess what your object/function/module is for by looking at its name, it’s probably too vague. Using Java reflection is also a bad sign :P
Another way to check whether you’re building something too flexible is to try to explain it to someone else. If they can’t follow what on earth you’re doing, it’s definitely too vague. Even if they can follow your explanation, another person who isn’t attached to the terribly clever idea you came up with may be a lot more willing to say “No, we don’t actually need this, this, or this. That part is really cool, though.”
You can also try asking yourself if there’s anything you could possibly take out of your design. If you were doing the thing manually (just imagine your database lookups are done in a filing cabinet or giant binder instead), what would be different? Would there be fewer steps? Fewer people/processes/forms/approvals involved? This can be a tough one for programmers because for many of us, super complicated “solutions” make us feel smart and we love to feel smart.
I’m not going to pretend I’m any sort of UI expert, but this definitely applies to UI too. Do you really need a setting for everything? No! Make a decision already, if you’re going to leave everything up to the user, what are you even for? At least provide a sensible default setting and hide the fiddly stuff no one cares about under an “advanced” tab or something.
The more complicated your idea, solution, or design is, the more chances it has to fail. That’s still true even if your argument wasn’t built on sand in the first place. Simplicity, on the other hand, tends to work a lot better. The fewer moving parts you have, the fewer things you have to worry about holding in your head while you build it. As a bit of an aside, if you’re ever wondered why even extremely expensive software produced by armies of highly paid contractors is so often terrible and buggy, it’s because there are too many moving parts for our poor fleshy brains to keep track of.
Simplicity is incredible timesaver, for both you and your team. Simplicity in your code reduces the number of bugs you create, and avoiding creating bugs is orders of magnitude faster than fixing them. It also makes it easier to fix your bugs when you do run into them. Simplicity in your design can be the difference between a project that actually goes into production and does something useful, and something that just never quite gets launched. Simplicity in your problem solving helps you catch silly mistakes that waste hours of your time, so keep it simple!
Don’t be a time thief. More precisely, if a decision has been made let it stay made.
This tip won’t necessarily change your personal output a whole lot, although you will have more time for your own work if you don’t waste it rehashing old decisions, but it will be fantastic for your team’s productivity. Being a better programmer isn’t just about how much you personally get done, it’s also about how much your whole team gets done. If you make your team better then congrats, you’re a better developer!
You will have to deal with decisions you don’t like as a developer. I’m not saying that’s a good time, but that’s not just life as a developer, it’s life in general. You can either accept those decisions like a grownup, or you can waste everyone’s time by fighting the same battles over and over.
Now, if something has substantially changed, like a new tool has been released or there has been an announcement that an open source library is no longer being actively developed, then it may make sense to reopen a closed discussion. But if you just don’t like the decision, you’re wasting everyone’s time. Even if you are technically right it’s generally faster to rework your codebase to recover from a decision that didn’t pan out than to have the same meeting over and over. It’s not just about the single decision, it’s about how you use your time.
It’s also about morale. It’s incredibly frustrating when you have meeting after meeting and finally decide something, only to have someone drag it all back up again a few weeks later. What was the point of all the earlier meetings if a decision that’s been made doesn’t stay made? If you want people to stop bothering to share their opinions, that’s the way to do it. Like I said last time, you have to be open to the idea that you could be wrong. You need your team’s ideas to make the best decision you can, and you can’t possibly get anyone’s real ideas when you convince them that it doesn’t matter what they say.
Arguing about things that are purely a matter of opinion is time-theft too. Curly brace on the same line as the method declaration vs the next line? tabs vs spaces? line width? No professionals bother to argue about that at work (the bar is a different story, however :) ), we pick a coding standard, set our IDEs to autoformat our code correctly and move on with our lives. Some arguments simply are not worth the time it takes to have them.
Speaking of arguments that have been had over and over and are a profound waste of everyone’s time, biology simply does not and never has explained the lack of women in computer science. We seem to drag this argument back up every few years in tech and every time it’s as foolish as it was last time. Google bro is simply the latest to waste thousands of hours of everyone’s time with ideas that have been debunked over and over. A grownup, not to mention a competent developer, would never have wasted everyone’s time with an argument that’s been hashed out dozens if not hundreds of times already. You simply can’t have someone like that on your team if you ever want to get anything done – even a competent developer, which Google bro certainly is not, couldn’t offset the collective productivity lost to rehashing well understood decisions over and over.
It’s perfectly normal to want to undo a decision you don’t like, just like it’s perfectly normal to want to stay in bed on a cold, wet morning and it’s perfectly normal to want to buy lunch and skip packing one. Wanting, however, is different from doing if you’re a grownup and you just can’t be a good developer without being a grownup. Even a lone hobbyist faces frustration and disappointment, you can either let those stop you in your tracks or you can set them down and make yourself useful.