Threadwell

Recent Notes

DemetriSpanos
Oct 06, 2026
NOTimothyLottes
Oct 06, 2026
bonzajplc
Oct 06, 2026

rfleury

224 items with this tag.

Aug 29, 2026
rfleury
Aug 10, 2026
I wasn’t joking!
Aug 07, 2026
A good way to evaluate one axis of quality of an abstraction is to inline every function call, and see how much duplicate work you can either deduplicate or turn into a loop (rather than several independent function calls).
Jun 02, 2026
The first way people usually learn code compression is by pulling common things out into helper functions, but in my view the complexity of adding a new entry point is often overlooked, and things quickly turn into a mess.
Mar 05, 2026
This ignores an important shift in the gaming industry, which is the dominance of art & production teams in producing content, and the shrinking role of programming teams doing the same.
Dec 15, 2025
None of these advantages are mutually exclusive with GUI, it’s just that legacy infrastructure doesn’t support it well.
Dec 04, 2025
On FOSS, and why we should pay for good software:
Oct 10, 2025
New post: "Multi-Core By Default"
Aug 19, 2025
Palettes should be first class functionality provided by the operating system for any program.
Apr 30, 2025
To the degree this is true, it’s only in a technical sense.
Dec 18, 2024
One of the most powerful lessons I learned as a programmer was to use combinatoric spaces to my advantage, rather than allowing them to explode into—for example—handwritten source code.
Dec 31, 2023
You are responsible for all code you ship to run on user machines, whether you wrote it or not.
Dec 29, 2023
Text files, while limiting and underpowered, feel like solid ground.
Nov 20, 2023
What do people mean when they say this? C doesn’t “have” a real string abstraction? C is a programming language which has tools for building APIs of many kinds, including for strings and many other things.
Nov 03, 2023
@Madisonkanna As someone who works full-time in C, I will say that a lot of the traditional educational material around learning C is not very good, because it was made in such a different hardware landscape.
Sep 30, 2023
People often do not appreciate how a more complicated language necessitates more complicated tools.
Aug 15, 2023
C and the toolchain need to be simplified & stripped down, not tidied up.
Jul 03, 2023
Decades of programming tooling and academic curriculum were built in an entirely different hardware landscape.
Dec 29, 2022
@AbnerCoimbre @sssmcgrath Ah good, important clarification :) Frankly I wouldn’t care for the project if it wasn’t held up as an important project in the Handmade sphere via avenues like HMS, so I think it’s relevant to distance myself from what I’d call bad faith business practice.
Dec 13, 2022
@mintyModulo It’s an incredibly useful skill.
Nov 21, 2022
@AllenWebster4th @MemoryArenaMain To clarify, I don’t write in first person plural for a reason—I don’t believe in “we”, and I don’t care to enforce my preferences on others.
Oct 11, 2022
While I'd love to say some cool future-of-computing ideas, let's start with the bare minimum:
Oct 03, 2022
Simplifying formats and protocols—particularly making them easy to implement from scratch—prohibits true monopolization.
Sep 21, 2022
“We don’t know what programming is.
Sep 09, 2022
@hasen_judy @convexcollider @croloris @sc13ts @AbnerCoimbre @AllenWebster4th @handmade_seattl Yes, we need simpler tools all the way down the stack, and that disqualifies C++.
Aug 30, 2022
This thread makes some good points about the UI design here, but the glaringly-obvious issue has little to do visual appeal, readability, alignment, or mismatched corners.
Aug 21, 2022
I have no idea how the idea that *data structures* are coupled to *layout of data structures in memory * got so pervasive with programmers.
Aug 08, 2022
@umpereiraai @bigrando420 Code should be organized by practical necessity, not by top-down design before any code has been written.
Jul 13, 2021
@nice_byte This GitHub issue is detestable and hard to read.
May 13, 2021
@nex3 https://handmade.network/manifesto
Oct 31, 2020
@ciano1000 @SasLuca @Jonathan_Blow @handmade_seattl I don't think I'd classify our goals one way or another.
May 22, 2020
@yunruse @cullend @GolerGkA @star_door_ @kevinwatters Haha, very true! In my mind, the preferable UI/UX model for an AST editor is an open question right now, but what I will say is that even the simplest possible controls I thought of turned out to be preferable over text.
May 15, 2020
@thnewlands @kevinwatters It is roughly 2 months in.
May 15, 2020
@cullend @GolerGkA @star_door_ @kevinwatters To clarify, the mouse controls are just a small editor feature, not really a demonstration of the most important parts of the code editing.
Apr 06, 2020
It is unfortunate that programmers are taught to ignore memory in favor of using RAII/GC/ARC/etc., despite that using memory constraints to one's advantage can dramatically improve speed, improve reliability, improve debuggability and reduce code complexity.
Mar 04, 2020
New programming blog post about the complexity and performance trade-offs of maintaining entity memory contiguity in games.
Dec 26, 2019
2019-12-26-thread
Dec 23, 2019
The new 4coder update, beta 4.1.0, has been awesome! I've already had a ton of fun adding custom editor features that both help out quite a bit when programming, or are just fun.
Aug 29, 2019
Why do we spend so much effort to encode programming language semantics into a textual form just so a parser can go through the error-prone process of ripping that same exact information back out? Why not work directly on a program's abstract-syntax tree? (1/8)
Jun 27, 2019
When writing graphics applications and demos, I've found loading in complex geometry without introducing any ridiculous dependencies (I'm looking at you, Assimp) is a pain and normally results in me writing some crappy special-case parser for OBJ so that I can throw some...
Apr 15, 2019
I wrote a custom data description parser with introspection features which can be directly used with C for introspection and code generation.
Jan 17, 2019
There is an odd tendency of modern society to make the assumption that if something is modern, it must be superior to the older equivalent, which is assumed to be incorrect or antiquated.
Jan 11, 2019
Problems I don't have when writing C and C++ code:
Dec 10, 2018
A recent lesson I've learned about #programming the hard way: Be *very* skeptical of mental models.
Nov 12, 2018
In modern day #software engineering culture, there is some sort of assumed equivalence between how source code appears and how well the program is written.
Aug 09, 2026
@rfleury makes me wonder why we don't have a tool (do we?) to visualize inlining like that (without actually doing it).
Aug 08, 2026
@rfleury John Carmack wrote about this: http://number-none.com/blow/john_carmack_on_inlined_code.html
Aug 08, 2026
@rfleury Some people will say that a good abstraction lets you understand the loops underneath, and some will say that a good abstraction means you don’t have to understand the loops underneath.
Aug 08, 2026
@rfleury The fundamental property of abstraction is to avoid repetition.
Aug 07, 2026
@rfleury If you got a concrete example of this, it might be worth making a video out of that, just saying! 😋
Aug 07, 2026
@rfleury Overall I’ve noticed that inlining is just amazing at surfacing issues with what the actual „abstraction” is - kind of that if I carve the function too early I’ll obfuscate the fact that maybe the actual function (behaviour) bends to that function rather than the other way around
Aug 07, 2026
@rfleury Assuming -O3, if you compare the assembly output before and after the exercise, do you see any meaningful difference?
Aug 07, 2026
@rfleury Do you have a favorite example from raddbg to look at?
Aug 07, 2026
@rfleury This seems like such good advice and hard to visualize without having practiced a couple of times.
Aug 07, 2026
@rfleury This is the first thing I do in every big refactor
Aug 07, 2026
@rfleury btw this sounds like a nice feature for a debugger
Aug 07, 2026
@rfleury couldn't resist
Aug 07, 2026
@rfleury I did this process to linearise the mutually recursive eval loop of a language - also found a very nice opportunistic TCO due to it.
Jun 03, 2026
@rfleury Can you share an open source project that follows this strategy? As someone deeply entrenched in the web and java world, I am finding it hard to wrap my head around.
Jun 03, 2026
@rfleury rad debugger is easy to read for such a complex project, I'm experimenting with the same long proc and noticed that when I add something I'm not constrained to early abstractions, I can connect dots much easier.
Jun 03, 2026
@rfleury Interesting! I was just reviewing code and thinking of solution when I read this tweet and realised "table + removing enum" solved it better than expecting the helper function to be used correctly.
Jun 02, 2026
@rfleury I like using lambdas or local functions to extract some common logic and put it behind a good name without cluttering things up outside
Jun 02, 2026
@rfleury yes! A similar problem comes when you follow retarded bob martin-esque rules like not exceeding 6 lines per function.
Jun 02, 2026
@rfleury I completely agree, adding a helper function rarely reduces complexity and often leads to a lot of argument bloat.
Jun 02, 2026
@rfleury oh I hate helper functions, especially the ones that get used exactly once and serve no purpose but hiding code
Jun 02, 2026
@rfleury I've come to refer to declarative as "just fucking say it" coding.
Jun 02, 2026
@rfleury I've been compressing in terms of "section functions" as opposed to helper functions.
Jun 02, 2026
@rfleury I noticed focusing on the data you work and how you work on it helps a lot
Jun 02, 2026
@rfleury I'll often inline every 'helper function' I find while coding.
Jun 02, 2026
@rfleury Entry point you mean indirection ?
Jun 02, 2026
@rfleury fewer entry points = fewer surprises
Jun 02, 2026
@rfleury I like giant matching functions with lots of helper functions as closures with limited scope.
Jun 02, 2026
@rfleury Only way to compress is dsl vv everything else is just the dsl with some extra boilerplate
Jun 02, 2026
@rfleury 100% agree, DRY can be extremely overdone.
Jun 02, 2026
@rfleury My mental model for this: Are you putting the mess in a closet, or are you actually organizing the it?
Jun 02, 2026
@rfleury A function explicitly limits the variables that its code depends on.
Jun 02, 2026
@rfleury I like this as it maps the problem with input on one side and output on the other.
Jun 02, 2026
@rfleury Does this imply if you took an external dependency, like Linux or matrix library, and started folding that code into your own, instead of calling into it, your code would improve?
Jun 02, 2026
@rfleury Can't tell just how many times I've pulled out something into it's own function only to use it once.
Jun 02, 2026
@rfleury I got a mess (kind of working fine but dirty) with c# extensions.
Jun 02, 2026
@rfleury db 설계에 앞서 모든데이터를 파일 입출력 으로 해서 최소 부하를 해보는것도 도움이됨
Jun 02, 2026
@rfleury Never thought of helper f-ns as code compression, you still have all the same stuff elsewhere.
Jun 02, 2026
@rfleury What about polymorphism and inheritance?
May 04, 2026
@rfleury macOS does this for ages, they have help menu search on cmd+shift+/, which filters all the menu commands for the app
Mar 06, 2026
@rfleury I think your analysis glosses over a lot of the production realities that shape how current pipelines develop and has nothing to do with art/programmer leanings.
Mar 06, 2026
@rfleury bad take is bad, the assumption that artists aren't interested in modularity and reuse is patently false
Mar 06, 2026
@rfleury This is genuinely a place where AI might be useful; comparing assets and deduping is a pain in the ass, but not necessarily all that difficult.
Mar 06, 2026
@rfleury This is the main contributing factor.
Mar 06, 2026
@rfleury Don't forget outsourcing.
Mar 06, 2026
@rfleury IMO If more artists and programmers were knowledgeable about the others work even it would make a huge difference.
Mar 05, 2026
@rfleury 7zip compresses across files.
Mar 05, 2026
@rfleury Programmers also build better games than art majors.
Mar 05, 2026
@rfleury Needs extensive early planning if you want that kind of flexibility in components.
Mar 05, 2026
@rfleury ???????????
Mar 05, 2026
@rfleury Look, the compiled machine code is like a few megabytes, maybe a gigabyte if it’s like a huge huge project.
Mar 05, 2026
@rfleury The strive for realism in games was a loss on many axes imo
Mar 05, 2026
@rfleury Strongly agree.
Mar 05, 2026
@rfleury I agree with the conclusion, but these examples, labeled “programmer” and “artist,” will only draw unnecessary attention to a false dichotomy.
Mar 05, 2026
@rfleury I expected a ragebait turn any second with "techbroes > artist cucks" or "le noble artists > smelly nerds" but this take is like 100% facts
Mar 05, 2026
TBH most games do have this pipeline, it’s just a technical artist that does it.
Mar 05, 2026
@rfleury I also think a big reason that programmers reuse artwork is because most don't like doing artwork in the first place lol.
Mar 05, 2026
@rfleury you provide no source but you talk confidently.
Mar 05, 2026
@rfleury The problem is that the west refuses to keep people employed for enough time for artists to learn this.
Feb 06, 2026
@rfleury Every time I seeyour videos I feel both an enormous amount of hope and an equal amount of despair.
Feb 05, 2026
@rfleury http://Shortcat.app but done at an OS level with more attention would be absolutely fabulous.
Feb 05, 2026
@rfleury I miss the days when Windows added and improved UI controls and apps rushed to adopt them.
Dec 16, 2025
@rfleury It is weird to me how there has been lots of advancement in tools that GUIs can be built on top of (Iced, EGUI, DVUI, technically Bevy_UI, Raylib even, and dear IMGUI)
Dec 15, 2025
@rfleury The only consistent api in Linux land is a terminal from the 70s.
Dec 15, 2025
@rfleury Day 700 of waiting until the uncultured realize that you can have a "GUI" terminal and you can have your stupid broken legacy serial console and limitless GUI and input options at the same time.
Dec 15, 2025
@rfleury Basically just sending character set binary data, so whether the Terminal or your own GUI application renders the data doesn't really matter.
Dec 15, 2025
@rfleury i'd agree on the first two, but remote is a hard sell
Dec 15, 2025
@rfleury Here before someone mentions X port forwarding :D
Dec 13, 2025
@rfleury It is fair.
Dec 11, 2025
@rfleury Software was "good" 10 years ago.
Dec 07, 2025
@rfleury When I was young and poor, looked for zero cost solutions.
Dec 06, 2025
@rfleury We’re trying to change this at @BuildWithGrove but we need folks to put addresses in their bio.
Dec 05, 2025
@rfleury I respectfully disagree, without open source or free software, I don't know if I would be here, and I can safely say that goes for many many others out there.
Dec 05, 2025
@rfleury Putting that genie back in the bottle is a Sisyphean task.
Dec 05, 2025
@rfleury One may read this (well written) article to get an understanding of reality.
Dec 05, 2025
@rfleury Open and prop SW have different benefits and penalties.
Dec 05, 2025
@rfleury the entitled 'give me free software or else' camp is dumb and enough of a minority it's not worth arguing with.
Dec 05, 2025
@rfleury Bold take but
Dec 05, 2025
@rfleury ie.
Dec 04, 2025
@rfleury In other words: people spending large amounts of time should be compensated for the labor they put into developing open source software.
Dec 04, 2025
@rfleury What do you make of Blender btw?
Dec 04, 2025
@rfleury I think this is a good new angle on the free/owned debate, because it's accountable that people who write open source software labor for others for free.
Dec 04, 2025
@rfleury Is the answer really lots of small walled gardens? I guess you can potentially keep the large corps out, though you need to vet every member to make sure they aren't "spies".
Dec 04, 2025
@rfleury We need more payed-for software where source is included.
Dec 04, 2025
@rfleury makes no sense, too many things need to support too many other things.
Dec 04, 2025
As someone who works in free and open source software, over time, I feel more and more in a similar way.
Dec 04, 2025
@rfleury FOSS altruism, much like Rust’s safetyism, is a symptom of decadence, not its underlying cause
Dec 04, 2025
@rfleury As you already know, I don't disagree with you on this at all.
Dec 04, 2025
@rfleury Yes...
Dec 04, 2025
@rfleury What do you mean by "furthest extreme of free and open source philosophy", the "all private software should be illegal guys", or simply the "we should make more free and open source software"?
Dec 04, 2025
@rfleury Excellent writing.
Dec 04, 2025
@rfleury The problem is not the exchange of money for value, but the single point of failure that is this exchange, as a requirement for using the software.
Dec 04, 2025
Nice writeup.
Dec 04, 2025
FOSS creates a bizarro software world where the 'higher values' they aspire to completely clash with a basic understanding of incentives.
Dec 04, 2025
Respectfully, those arguments are pure hypocrisy.
Oct 23, 2025
@rfleury Cool idea! I added a similar model to my language after reading this.
Oct 14, 2025
@rfleury Arenas : Memory management
Oct 11, 2025
@rfleury Also interesting is the notion of persistent threads on the GPU
Oct 11, 2025
@rfleury I read your post and it reminds me a lot of how I programmed using MPI.
Oct 11, 2025
@rfleury That's a very cool way to exploit parallelism in branchy CPU code! Never seen it done that way before.
Oct 11, 2025
Imagine your code as a bustling kitchen; each recipe station runs on its own stove; by thinking multi core by default, you reshape functions into independent chefs coordinating only when necessary; this approach cuts memory traffic, boosts cache usage and turns code maintenance into composing harmonious solos rather than conducting a crowded orchestra; each program hums with parallel flair.
Oct 10, 2025
@rfleury I used to use this technique in Love2D with Lua of all places, where spawning threads is essentially running an entire separate LuaVM, sharing data using FFI types and inverting the structure like that made it very easy to parallelize code
Oct 10, 2025
@rfleury Shouldn’t single-core array summation be faster than multi-core, since summing is bottlenecked not by computation but memory fetching?
Oct 10, 2025
@rfleury I mean, it is getting hard getting a single core cpu this days.
Oct 10, 2025
@rfleury Great article (and the other previous linked therein)! I like the idea of thinking of the codepath architecture as shapes and cycles to identify opportunities for parallelism
Oct 10, 2025
@rfleury seems like SPMD and logistics logic.
Oct 10, 2025
@rfleury Is this influenced by CSP? C.A.R.
Oct 10, 2025
@rfleury With Go this is very easy
Oct 10, 2025
@rfleury A similar style is somewhat common in the Linux server world, where it is called "thread-per-core".
Oct 10, 2025
@rfleury Thanks for sharing this Ryan!
Oct 10, 2025
@rfleury My company sells stuff to make this easy.
Oct 10, 2025
@rfleury Holy shit, this is such a cool idea; I've never thought of it this way.
Oct 10, 2025
@rfleury I have not run across this interesting pattern in 20 years of gamedev.
Oct 10, 2025
@rfleury might be interesting to see an implementation of parallel execution for conditional statements
Oct 10, 2025
@rfleury that's nice but it's funny if you think people can handle any amount of coding sophistication, drive safely in the rain, or roast a chicken without hurting themselves.
Oct 10, 2025
Excellent post, I've written plenty of shaders but never thought to write CPU code in the same way.
Oct 10, 2025
@rfleury are people more commonly doing this style in game dev?
Oct 10, 2025
@rfleury Damn, this is highly illuminating.
Oct 10, 2025
@rfleury Can you say more about this "...
Oct 10, 2025
@rfleury It seems like there's some problems with load balancing in this system.
Oct 10, 2025
@rfleury Do you suggest to do it right after main, and continue throughout the entire program?
Aug 21, 2025
@rfleury @rfleury how do i go back and forth when navigating code using raddbg? I usually that using ctrl+ left/right or using 4th and 5th mouse button.
Aug 21, 2025
@rfleury What would that look like specifically?
Aug 20, 2025
@rfleury What is the benefit of having it in the OS rather than in a library?
Aug 20, 2025
@rfleury I understand it being really powerful when you know what term to search for, but if it's not known to you, having dropdown menus is still useful to find out all the functionality of that software, e.g.
Aug 20, 2025
@rfleury I think we all can agree that the current OS vendors cannot be trusted with these decisions
Aug 20, 2025
@rfleury for those unable to view the video, explain?
Aug 20, 2025
@rfleury Man, hard agree! Then almost everything would become optionally keyboard-centric.
Aug 20, 2025
@rfleury Problem is *you* have to design the operating system or the command palette will suck
Aug 19, 2025
@rfleury Both is good
Aug 19, 2025
@rfleury I remember as a kid using AutoCAD for the first time and thinking the command line interface was great, not needing to wade through drop-down menus.
Aug 19, 2025
@rfleury MacOS is slowly taking spotlight into that general direction
Aug 19, 2025
@rfleury Would you really want to use an OS-provided palette over the one you've rolled yourself, though - even in the improbable scenario that MS et al.
Aug 19, 2025
@rfleury What is this editor?
Aug 19, 2025
@rfleury It would be amazing if I could see (and use) such an operating system in my lifetime.
May 01, 2025
@rfleury individual malloc/free is a common C practice and is the fair comparison; group allocations are not the norm in most programs especially in the hand-off ownership situations where unique_ptr would apply.
May 01, 2025
@rfleury Look at any large codebase and you'll see a bunch of new/delete calls.
May 01, 2025
@rfleury Do you have any example of this?
May 01, 2025
@rfleury Well said.
Apr 30, 2025
@rfleury Saw a Casey Muratori video about people who think in single unit lifetimes vs group allocations etc yesterday.
Apr 30, 2025
@rfleury There is exactly zero pain in debugging unique_ptr variables these days.
Apr 30, 2025
@rfleury I miss the point you are trying to make
Apr 30, 2025
@rfleury This isn't such a strong argument considering there's a "leak" with the regular call to `new`.
Apr 30, 2025
@rfleury Too much words, but unique_ptr is*really* zero cost.
Apr 30, 2025
@rfleury Generated assembly or other supposedly better ‘hand-written’ options for memory management are IMO just distractions when talking about unique_ptr.
Apr 30, 2025
@rfleury I bet std comitee wrote thousands of lines for this
Apr 30, 2025
@rfleury I'd use C more if attribute(__cleanup__) was standard and a little less cumbersome.
Apr 30, 2025
My experience has been different.
Apr 30, 2025
@rfleury Also people will say this garbage and then show you the assembly in -O2.
Jan 24, 2025
@rfleury thank you for this thread- read it a while ago, but now working on a game and something *clicked* when thinking about modeling data in this way (understanding the power of the 2^n benefit)
Dec 20, 2024
@rfleury interesting projection of combinatorics system into coding system.
Dec 19, 2024
@rfleury I completely agree.
Dec 18, 2024
@rfleury example?
Dec 18, 2024
@rfleury @threadreaderapp unroll
Dec 18, 2024
@rfleury At what point do you think you should convert a switch statement to "behavior flags"? Suppose there are N entity types and K behaviors.
Dec 18, 2024
@rfleury Maybe you already wrote this somewhere, but I'd be interested in seeing a practical example of your approach, even a basic one.
Dec 18, 2024
@rfleury any concrete example?
Dec 18, 2024
@rfleury This reminds me of games and simulations, where entities have a set of attributes.
Dec 31, 2023
@rfleury aah!
Nov 20, 2023
@rfleury Most developers do not understand the distinction between language feature and standard library.
Nov 20, 2023
@rfleury A charitable interpretation would be: For a lot of programs it's quite useful to have a common, expressive interface with basic and 'safe by default' utilities around strings.
Dec 29, 2022
@rfleury @AbnerCoimbre @sssmcgrath Thanks for sharing this.
Dec 29, 2022
@rfleury @AbnerCoimbre @sssmcgrath Go open-source
Dec 13, 2022
@rfleury @mintyModulo It's because most debuggers suck, not to mention most are text based and not GUI based
Dec 13, 2022
@rfleury @mintyModulo thanks, unix
Nov 21, 2022
@rfleury @AllenWebster4th @MemoryArenaMain just passing by
Aug 30, 2022
@rfleury It is impressive how quickly they're managing to trash decades of work improving the user experience when they decided Windows should be "free" and that their former customers would be the product they sold.
Oct 31, 2020
@Jonathan_Blow @rfleury has been working on Dion which will be presented at @handmade_seattl which looks like a very interesting take on visual programming languages
May 15, 2020
@rfleury @thnewlands @kevinwatters this is really special ty
May 15, 2020
@cullend @GolerGkA @star_door_ @kevinwatters To clarify, the mouse controls are just a small editor feature, not really a demonstration of the most important parts of the code editing.
Apr 08, 2020
@rfleury Just a conversation on this topic today.
Apr 07, 2020
@rfleury I'm that kind of person who asks the "why" of things, and how they were made from its core, but by not "re-inventing the wheel" you can save a lot of time.
Apr 07, 2020
@rfleury Nowadays there are a lot of software done and debugged to be used, the way i see that fact is, that thanks to that software you can create new software faster....
Aug 29, 2019
@rfleury You can still have the representation be textual but have the ide give you tooling of this kind.
Aug 29, 2019
@rfleury For a moment I thought you were revealing your new lisp-like
Aug 29, 2019
@rfleury Are you familiar with @stevekrouse and his http://futureofcoding.org community?
Aug 29, 2019
@rfleury Would you consider tools like Unreal's blueprints something pointing in that direction?
Aug 29, 2019
@rfleury I was having similar thoughts about this.
Aug 29, 2019
@rfleury Why aren't we working straight in assembly code? ;)
Nov 12, 2018
@rfleury Good software design for hardware and for its human maintainers aren’t mutually exclusive.

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