declarative, reproducible emacs (the right paradigm) – how to

Hi everyone, this is Jake here with Straightforward Emacs. Today we'll be going over declarative reproducible Emacs with Straight. And use package. I teased this idea in a previous video and I had a lot of people asking for it. So I got around to producing the video and writing up a little blog post. Now from now on I've decided that full technical details and writeups will be located at my blog. And these videos will serve as a softer introduction as well as a demonstration so that you can get a feel for the ideas, concepts, and interactions that just don't come across very well in a blog post. So with that said, what do I mean when I say reproducible declarative Emacs? Well, what I mean is that I want to be able to take this Emacs configuration and use it on any machine and have a guarantee that the machine and Emacs are going to act in the exact same way. This doesn't only mean things like, oh, I have the same color scheme or the same key bindings. It means that my packages are pinned to a specific version. Now, we have declarative. What does that mean? Well, here it goes handinhand with reproducibility. And I basically mean a configuration that defines Emacs's behavior in a welldefined way. So for example, rather than installing packages by hand, um we write our in our configuration that we would like such and such package to be installed and our installer or our whatever bootstraps our our EMAC configuration will ensure those packages are installed. It's not simply up to us. So if a package is ever missing, it's guaranteed to be installed later. If we adhere strictly to this declarative principle, which gets far more complex as we'll see, it means that the entirety of our Emac setup can be successfully defined and understood with a single file. So, let's do a quick review of Straight. And use package and then we'll get into the meat and take a look at my configuration. Straight. Manager for Emacs that I use for two main reasons. um one packages are downloaded from source and two packages can be pinned into a lock file really easily. Now what does this mean for you? This means that on any machine we're guaranteed to have the same package version installed and that's pinned with the commit hash. The next thing that we'll want to use is use package which now actually comes with Emacs but it's essentially a macro that will expand to a complex configuration for your packages. Here are some of the core ideas here. We can uh configure variables inside a use package block. We can add hooks. We can configure variables with the customize interface. And we can execute arbitrary code on package initialization. All right. So now here we are inside let's call this my sample innit.el. This is essentially a copy of my init.el L, which I'll review in another video, but paired down and removed some of the distraction so that we can see what a minimal uh example might look like. Uh so the first thing that we do is we bootstrap straight. And I'm just going to walk through this line by line. Basically, um the first thing I do is bootstrap straight. Um and you'll see that from here on I essentially put every single line of code that can exist in a use package block inside a use package block. This doesn't only include package settings but also key bindings we can do with general.el. The blocks also do not depend on each other and they also do not depend on the order that they are placed in. This means that we don't have to be concerned with the order of package loading or really the order of any code in our configuration. And that's what I mean when I say I want a declarative configuration. I want to be able to declare the behavior of a package and not worry about how it interplays with another piece in my system. Okay, so let's take a look at how I configure Emacs and then we can go more in depth to the most complex things. We can actually configure Emacs with use package. And what it lets us do is use their really nice clean macros to set variables. So on it, I set a few basic variables. I set scroll conservatively. I set use short answers whatever like anyone else. I also set default a few variables and for that I put that inside a config block because I want that to happen later. I also execute a little bit of arbitrary code. For example, I enable global display line numbers mode and I enable fringe mode. Now here is something really interesting. We can configure key bindings for Emacs within this use package Emacs block. Now remember, I'm using evil mode here, which amazingly is completely unimportant because evil mode is 100% confined to its own section at the bottom of my configuration. So if one day I decide I don't want evil mode, I still have these basic Emacs keybindings that have nothing to do with evil. That all they have to do with is with Emacs. Let's take a look at a hook. Now this is how I set up my saving and recent files. I use recent def. I use save hist. I want to enable recent F mode when Emacs boots up. So to do that I take use of the hook and I set after init I add on the recent F mode. And this is pretty much equivalent or exactly equivalent to add- hook. It's just a little bit cleaner and it it fits in with the use package ecosystem a little bit more. What else is interesting here? Well, like I said, we can execute arbitrary code to keep our configuration very small. Inside a config block, I'm able to have a do list um and an add to list. So, I can add a few extra commands to the golden ratio extra commands list. And this is all inside golden ratio mode. Everything else is pretty similar. It just follows this idea. We have a package and everything related to that package is simply inside that use package block. If I don't want golden ratio, I comment it out and I'm not going to have any errors because I don't mention it anywhere else. Let's see if we can find a light a slightly more complex one. Here's my org mode configuration. This is a great one. Um what do we do here? We're using a a more advanced straight feature. We're going to pull or mode directly from GitHub from the main branch because I like to be on um the main branch of org mode. Sometimes you can get a stale version that's bundled with Emacs. This guarantees that I'm right on the fresh cutting edge of GitHub and I simply point it to the repository. This is a great straight feature. I also set key bindings here. I have diminish which provides a very clean mode line for me. And I have a hook here as well. I have two hooks. Then I set a few custom variables. And we can just set a bunch of variables here. Now let's take a quick peek at my real configuration. Evil trips a lot of people up. How do I manage having evil and pure Emacs? You know what if I don't want evil? Like am I going allin? Well, every evil key binding that I manage or that I want that's not standard goes inside the use package evil block. It ends up actually all being key bindings. For example, I have a leader key sort of inspired by space emacs. So, if I press space, I have all these these these quick keys and it's all defined inside use package. I have some remappings. I have some other config and this all is contained inside this block. So it turns out that the most efficient way in my opinion to produce your Emacs configuration is with this declarative reproducible mindset. All right. Now I hope that I've laid out my thesis for the organization and the motivation of my Emacs configuration. These principles were inspired by Nyx um which made me realize that I have been pursuing these principles of declarative configurations functional programming through Emacs for years without knowing it and I imagine many of you have as well. So this guide should put you on the right track. If you're interested in more technical information, please check the blog post. It's a very detailed guide to getting started. It should give you all the information you need to use straight and use package. And if you have any questions as well, in addition, feel free to leave a comment. I try to reply to all of them.

In this video I discuss my theory behind creating a declarative, reproducible Emacs configuration. What does it mean, why should we do it, and what tools do we have? I finish with a brief tour of a simple configuration. For full technical details, see the blogpost: https://jakebox.github.io/posts/2026-02-05-declarative_reproducible.html