John Carmack and John Romero reunited to talk DOOM on its 30th Anniversary

What a treat it was listening to two legends talk with great passion about software they made 30 years ago.

I absolutely loved their answer to a question regarding better enemy AI, which boiled down to “better enemy AI doesn’t automatically make for a more fun game”. (they put fun and player experience first and aren’t tricked by shiny new toys)

Was also interesting hearing Carmack lament how so few much loved games release their source code (he attributed doom’s longevity partly to the release of its source code)

Monster infighting added so much to the game and was relatively "cheap" to program.

What other games even use it apart from Doom, Quake and Half Life? (HL 1 had some impressive AI)

They gave a couple examples of the kind of AIs that don’t make games fun. One was some game (real or hypothetical) where you fight a small drone that’s very smart and fast, so it’s hard to shoot at. Another was where the enemy goes off and concocts a sophisticated plan to beat you.

They described how the player wants to feel like the game play is about themselves, not about some ultra smart enemy. So big and dumb enemies tend to work best, even though they don’t use sophisticated AI by today’s standards.

It was like the the Jurassic Park meme: just because we can doesn’t mean we should.

(Also very strong agree on monster infighting, it added so much depth, as a kid I didn’t even know monsters could infight until the level with cyberdemon and arachnotron in the same room)

Consider an FPS AI with perfect tracking and aim, or a starcraft AI with perfect blink stalker micro. It's a smart play, but not fun for the player

Or the Deus Ex “ai” which people praised as feeling very intelligent- but was just programmed scripted sequences based on what the player most likely would do.

So a state machine? My unchecked suspicion would be that 99% of all enemy AI in gaming history are state machines of some sort.

all enemy AI in gaming history are state machines of some sort.

Couldn't that be said about all natural intelligences too? "state machines of some sort" is a very broad characterisation fitting almost anything.

Yeah, in the end it's all if-this-happens-do-that under the hood. And that's important because game AI must be deterministic. Otherwise reproducing bugs would be impossible.

Aren't most elements in video games, including the player characters, state machines?

Do you have a source? I had never heard this.

sophisticated AI != aimbot accuracy

Some games are so complex that AI on the higher difficulty levels resorts to cheating. I understand the rationale behind it, but it has always rubbed me the wrong way.

The original Halo trilogy, Breath of the Wild/Tears of the Kingdom, The Last of Us, and Horizon: Zero Dawn, to name a few. A great mechanic!

A lot of Last of Us players don't realise you can grab a hunter or infected, and then "feed" them to a clicker.

Off the top of my head, several roguelikes (e.g. ADOM, Caves of Qud, ToME) and several entries in the TES series (e.g. Daggerfall, Skyrim) support it.

I also remember at some point playing an RPG where you found an ongoing even fight between two armies and you could join one to make the fight go your way, but I don't remember what it was.

Sounds like Skyrim and the fight between the Empire and the Stormcloaks.

Marathon had monster infighting.

Marathon is a game series from Bungie, the first version released shortly after Doom, but only on Macintosh.

There are defense drones [0] that aid the player and later on enslaved cybernetic aliens [1] that revolt against their alien overlords.

As in Doom, if an enemy would accidentally hit another enemy, they would fight one another.

The Marathon series can be played on modern computers using Aleph One [2]

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[0]: https://marathongame.fandom.com/wiki/Marathon_Automated_Defe...

[1]: https://marathongame.fandom.com/wiki/S%27pht

[2]: https://alephone.lhowon.org/

In Tears of the kingdom you can shoot muddle buds to monsters and they’ll start fighting each other.

The original Turok on the N64 had this too :) It just was very hard to trigger for obvious reasons, as humans and dinosaurs spawned far apart

Minecraft. Triggering it so skeletons kill creepers was the primary way to get music discs

Halo, you can let the Covenant and Flood fight each other and clean up whoever is left.

Monster Hunter has it, it's pretty epic seeing massive creatures fight each other and you, a tiny human with an oversized weapon, running for your life and / or awaiting your opportunity to kill them and use their corpses to make new weapons/armor.

Was also interesting hearing Carmack lament how so few much loved games release their source code (he attributed doom’s longevity partly to the release of its source code)

I blame middleware. Hell, middleware makes even releasing the mod tools harder, i remember when i worked at some gamedev company and we wanted to release the editor for our game and the company behind some middleware we used wanted us to buy a separate license for it.

Is there any organization that buys up rights to classic games and then releases them as open source, removing/replacing third party dependencies in the process?

If not, we should start one.

Javier Chavez bought Keen Dreams with some crowdfunding help and GPLed its’ source. (I’m guessing the graphical and other game assets remain proprietary) https://en.wikipedia.org/wiki/Commander_Keen_in_Keen_Dreams#...

Thanks! Having the source code be open source is definitely a step towards preservation.

I blame middleware

I think John Carmack does too - from memory Doom's source release had no sound code because it was done externally.

The original F.E.A.R. always stuck out to me for its AI. Not because the actual AI is very smart - most enemies still are dumb lugs that try to get the player and have basic "is seen, rush down" AI, but because the player gets a lot of feedback for their actions.

The main way to trick a player into thinking an AI is smarter than it actually is? Have their voicelines "cheat" a bit and respond very vocally to things the player does near them; even if the enemy can't see the player, the idea of "oh shit, they heard that" can really enhance the seeming intelligence of the enemies.

Given that F.E.A.R. is a horror themed shooter, that's a big boon.

It's a testament to the game that its AI is still this memorable. Have there been any advances in that area since then? I'm not at home in the singleplayer FPS genre anymore, how do the SP campaigns of the newer Halo or CoD games hold up?

Far Cry enemies were relatively smart in the first episode too.

Was also interesting hearing Carmack lament how so few much loved games release their source code

Couldn't agree more - it's sad that id is/was one of the exceptions.

I'm still waiting for the GoldSource engine to be open sourced...

Wasn't GoldSource based on the Quake engine? I'm reading that it's heavily modified, mainly in terms of enemy AI.

Yup - mostly Quake, some QuakeWorld, some Quake II.

I remember when, in 1993, my boss bought a $6000 Windows machine at work - to play Doom.

Edit: He had already mentally checked out of this job and was transitioning (already working at) a different company. As a comp-sci computer graphics specialist, he dug Doom at multiple levels. Me - I was not impressed by Doom - probably because I didn't have his background to understand what a feat of engineering it was to get such performance out of a 1992-era CPU.

If you played other games at the time, there wasn’t really anything else like it. Wolfenstein and similar existed, but Doom was a significant advancement. Us lowly console players were many years from anything similar.

I still feel Marathon was at equal level, even surpassed it in several areas. And released maybe a couple of months after Doom.

But it was only known by Macintosh gamers at the time.

In which ways I feel Marathon was better:

- better light effects

- ability to look up and down

- secondary effects on various weapons

- deep story (done through interactions with computer terminals)

- variety in physics based on levels and weapons (e.g. grenade launcher) is affected by physics

- having to deal with oxygen depletion in some levels

- some AI that aids you (defense drones that support your fight against the aliens)

- more variety in level objectives (e.g. prevent humans from being killed by aliens)

- more comprehensive multiplayer (I believe Doom supported 4 players; Marathon supported 8 - Marathon has more types of multiplayer games than just Deathmatch).

I think Jason Jones [0] was probably at an equal level as John Carmack at this point in his career.

A deeper comparison between the 2 game engines can be found here: https://www.doomworld.com/forum/topic/78805-marathon-vs-doom...

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[0]: https://en.wikipedia.org/wiki/Jason_Jones_(programmer)

Sounds like an example of releasing a good product on a relatively unpopular machine.

Marathon was better on paper, but as far as visceral gameplay experiences go it lagged behind Doom quite a bit

Most of the Id games were significant advancements (up to Quake at least); in addition to Doom, the other major revolutions were:

- Commander Keen (smooth scrolling)

- Catacomb 3D/Wolfenstein 3d (pioneered ray casting on PC)

- Quake (introduced full 3d worlds)

As a side note, Terminator: Future Shock ([1]) had 3D enemies in '95 - but still 2D-sprite explosions and weapons.

[1] https://en.wikipedia.org/wiki/The_Terminator:_Future_Shock

Jedi Knight: Dark Forces II still used 2D sprite explosions and weapons in 1997. Was Terminator: Future Shock true 3D? I seem remember it used the Daggerfall engine which was 2.5D.

First generation 3D games were kind of a mess IMO. They usually hadn't figured out the controls yet and polygon counts were so low I always thought they looked worse than sprite based games. It isn't a surprise to me 2D-sprites hung around for awhile. Billboard sprites are still a pretty good/cheap choice for symmetrical things like explosions.

Playing the limited shareware release of Doom the very first time in single player mode was already incredible, but it was the multi-player mode that was mind blowing.

It would be fun to see a graph with sales stats of NE2000 clones around that time. They were the cheapest Ethernet expansions boards at the time, and one of the few that Doom supported.

Yeah, I can vividly remember when my friends and I booted up a copy of shareware Doom the first time. We'd played the heck out of Wolf3D and so on.

Nothing was like Doom when it came out. It was shockingly, impossibly smooth.

I was at E.A. working on the ill fated 3D0 OS video subsystem when Doom was released. The game was immediately installed on everyone's PCs, "for research", and for the next week or two absolutely zero work occurred at Electronic Arts.

While 3DO may not have been a success, at least you could play the legendary HoMM3 and Star Control II on it.

Being an OS developer for the 3D0 was enlightening, primarily because very little of the highly publicized 3D0 technology actually worked. The OS team was expected to fix the hardware bugs, while maintaining all the marketing hype. Plus the executives were early spending the money they expected to earn and were half checked out during the critical "nothing works this cannot be delivered" meetings. It was the cascading cluster fuck of all cluster fucks, as E.A. had no capacity to realize this "ambition", just executives capable of selling the idea.

Interesting! My vague recollection (as a kid at the time) was that the 3DO really did deliver some impressive stuff but just at a very high price. Of course by the time the Playstation was released it was game over for 3do (and Atari, and Sega).

I worked on the PlayStation OS too. Very different everything. I was Sony Computer Entertainment's first software engineer hire, promptly sent to Tokyo to help finish the system.

I remember playng Doom at a common PC (no graphic card). Was there something special about running Doom on some expensive machine? (FPS wise?)

3d cards did not exit at the time, everything was done on the CPU.

And yes your pc had a graphic card, or you wouldn't have had anything to hook your screen onto ;)

Yes, sure, I wanted to say "advanced graphic card with GPU".

Anyway, the USD 6k price tag was very high since I remember running Doom on a sub USD 2k PC. Most probably closer to USD 1k.

I think in 1993 you could easily still spend $6k by buying the top end 486/pentium CPU from intel, 8mb ram, CD-ROM, large (for the time) HDD, 17" monitor, etc. It wouldn't have a GPU but the latest tech always cost a big premium (it might be just 50% faster than a good but non-top-end system but cost 2-3x as much).

EDIT - looking at some ads in the December '93 issue of Computerworld [0] there's a Compaq ad saying "the Deskpro with Pentium starts at just $3,199" (both the "starts at" and the "just" make me think you could make it cost a lot more than $3,199, altho you could surely also play Doom on a cheaper computer).

[0] https://books.google.de/books?id=WESBpiNtNTEC&pg=PA19&hl=en&...

It wasn't just the engineering. The immersion was unprecedented in videogames, which was supported, besides the obvious rendering improvements, by lighting and sound.

Experiencing for example, lights suddenly turning off and monsters appearing and making noises behind the player, was very intense and novel.

(There were also other revolutionary aspects in Doom, notably, multiplayer)

I find it impressive that the doom modding community is as vast and varied as it is.

I could easily keep myself entertained with doom wads for quick a long time.

Is there another game that has that level of dedication? I think sim city 4 does but doom is much much older.

Part of this comes from its simplicity. Maps are relatively fast to make. DoomBuilder and TrenchBroom have made more 3D maps practical. Duke3D and its engine has a smaller yet continuously active community. There are others.

Agree. I got into duke3d and shadow warrior mapping back in the day. The fact that these games weren't truly 3d mandated that you designed the maps 2d first, ie drawing the layout of the map top-down, and then switching to 3d mode and assign textures to walls and floor/ceiling, as well as adjusting their height. That forced you to approach level design in a specific way, it was easy to get into.

When unreal was released I tried to create some maps for it, but was quickly overwhelmed. You're basically thrown into blender and supposed to construct a 3d world from cubes and other simple 3d shapes. I ended up with I think one and a half somewhat decent levels, but they still felt clearly inferior to any of the official maps.

The complexity of modern FPS completely kills the modding possibility.

I think DOOM3/Half-Life 2 is the last generation of engines that still allow a decent amount of mods (HL2 does have quite a few high quality mods), but everything afterwards is simply too complicated for hobbyists to compete with professionals.

Skyrim is a counterexample, which is heavily extended through both an officially supported scripting engine, and unsupported code hooks.

I thought about this so I only mentioned FPS :P

But still, even with the toolset Skyrim is still pretty time consuming to develop large mods. It won't be possible without its dedicated fans -- which is kind of ordinary for RPG but less for modern FPS.

Thief 2. There's an incredible amount of fan mission content for it, ranging from relatively simple levels, to one-off-masterpieces, to incredibly elaborate full-game-length mission packs.

Warcraft 3. It shipped with a powerful but approachable map editor, had thousands of custom maps and game modes, and spawned two separate gaming genres (Tower Defense, MOBAs).

Morrowind and Skyrim. Both were solid base games to build on top of, both shipped with a powerful creation kit, and both have an incredible amount of modded content available for them.

Technically, Neverwinter Nights would also qualify, but that was less of a game and more of a DnD dungeon master sandbox.

What are some of your favorite Thief fan levels?

If you're looking for any unusual recommendations, I'm not the best person to ask! I've only tried the more popular ones, but The Seventh Crystal, Gathering at the Inn, The Inverted Manse are my favorite stand-alone missions.

A big new campign was just released called "Thief: Dark Parade" which has made a lot of buzz across the fanbase for its excellent level design.

It has animated cutscenes, voice acting, pretty much on the level of original game(s).

Modern-day I'd look at Minecraft or even Roblox; mind you, the latter is less modding and more building things in the tools that the game / dev tools give you.

Modern Minecraft modding is truly astonishing.

The kinds of things they've added to the game are absolutely incredible, and it feels like every couple of months a new mod comes out that makes a huge impact on the landscape.

It's very cool. I've been thinking about trying to contribute to some of my favorite mods, but I have to start learning this stuff first.

StarCraft Brood War

There are still high level playes participating in tournaments with prizes.

Also some custom games scene, but it is much slower than in the past. There is some website that tries to collect custom maps: there are hudreds of thousands of them.

StarCeaft spawned: MOBAs, turret defense, even had something similar to Among Us. ..

Is there another game that has that level of dedication?

Quake is more difficult to mod (map building is more complicated and you need to build models rather than sprites) but it seems to have a few active source ports.

Super Mario World and Super Mario 64 arguably

Half-Life just had its 25th anniversary. It’s crazy to think there were only 5 years between those two titles.

When I think about that period in gaming I just trip out.

We are as far away from that period now as that period was from the birth of video games. Tennis for Two, Space Wars, Pong, Super Mario, DOOM, Quake, Half-Life.

Compare that 20-year evolution to the evolution of gaming in the last 20 years. You can see areas where games have gotten vastly better, not just graphically or cinematically, but with level design, mission design, characterization, contextual integration, procedural elements.

But still nowhere near the explosion of the first 20 years as innovation poured in, and all of the main players were scrappy young companies, ready to innovate in an atmosphere where it still meant something to create entirely novel experiences that challenged the player.

You can also very easily see an industry-wide shift in game design after both GTA and Minecraft, which seemed so far apart at the time but really were about a decade apart. What comes next?

As a teenager during that time it feels easy to say that we idealize those periods of youth, but objectively speaking there was never a period in gaming history with such drastic speed of innovation between the late 90s and early 200s.

Agreed! Not as stark a contrast as Doom to Half-Life, but even Quake (1996) to Quake III Arena (1999) was an insane leap technologically.

For sure; if you look at 15, 20 year old games now vs today's, you can see it's more evolution than revolution, in terms of gameplay mechanics, graphics, scale, etc.

Not that it's not impressive; look at the PS5 tech demos (large scale areas that players can go through fast without loading times thanks to fast storage), or the Unreal Engine demos, e.g. the Matrix one you can download to the PS5 or the one where they highlight generative level creation.

But it doesn't feel as revolutionary anymore. Mind you, that may just be fatigue, or "getting used to" things quickly.

I think objectively 2D to 3D was a massive jump. Also the FPS genre which is maybe the most successful gaming genre of all time being invented. Can't even think of a new genre of game that's been created in the last 10 years. I guess the sandbox game Minecraft was a little over 10 years ago, that's one.

Even Minecraft didn't really invent the sandbox, it just polished and popularized it.

A new genre in the last 10 years? Probably nothing really. We're probably past the point of new genres being invented until the technology dramatically changes.

We'll see some wild Genre Fusion though. I'm excited for that. I can't wait to see what happens when we stop just stapling "RPG" to every genre and start to really innovate.

That's not true, we now have strand-type games. ;)

Nanite and Lumen are definitely witchcraft. That tech demo left me in awe at what humanity has been able to accomplish. "More evolution than revolution", what a fitting phrase.

I wonder if we will live to see another such revolution in the wake of mature generative AI tools? If creating a game of the density and caliber of Red Dead Redemption 2 becomes feasible with a modest team of 10?

It was a wild time; as they said, Doom was made in (just) one year; while in a sense the games of back then are comparable to indie games of today, even indie games take longer to build these days.

That said, it's a work/life balance thing too; the Doom team did pretty much a year of grinding, pizza and coffee fueled 14+ hour workdays.

And just six years between that and HL2/Doom 3, the first big games to introduce proper physics. Shooting a box and watch it move, or the pick up a soda can/shipping container and throw it around was mind blowing at the time.

Not to mention the graphics evolution; compare G-man from HL to HL2.

It's also worthwhile to remember where the team honed their craft, as was also mentioned in this session: The early id team worked for a publisher called Softdisk that provided a game subscription where customers received a new game every month. This was basically a way to iterate on the practice and process of game development in one month cycles. The shareware relase of Doom had four months of development, which sounds crazy short by today's standards, but for them it was unusual to have so much time.

There's several talks on Youtube by John Romero where he tells the story of the early id software, e.g. https://www.youtube.com/watch?v=E2MIpi8pIvY

The shareware relase of Doom had four months of development

This is incorrect. Doom took a year.

This was literally in the first answer Carmack gives on the Twitch stream yesterday - https://m.youtube.com/watch?v=QvAkaJsvAXs&t=493

GP talks about the shareware release, which was just the first episode, not the full game.

https://doomwiki.org/wiki/Shareware

Doom was released (as shareware, upgradable to the full version) after a year in development.

Yeah, from what I can tell Romero is referring to Wolfenstein taking 4 months to shareware release here: https://youtu.be/QvAkaJsvAXs?t=3580

Sokpop is running a similar approach on Patreon. They have 4 devs and have released over 100 games since 2018 https://www.patreon.com/sokpop/about

Sokpop is fantastic. A tiny game coop based out of Scandinavia releasing interesting tiny projects every month.

Wikipedia says 1 year: official team development started Nov 1992 and the first episode was released Dec 1993. IMHO this is underplaying it given Carmack started on the engine before that and it evolved from Wolfenstein 3D.

https://en.wikipedia.org/wiki/Development_of_Doom

Yep, I remember him adding emphasis while reminiscing the Softdisk era and how forcing themselves to push new stuff on a tight schedule may not have been the right conditions to produce anything of quality but it gave them the right conditions to hone their skills.

What I'm uncertain is, whether this was mentioned in the book "Masters of Doom" or Carmack's interview on Lex Fridman.

For those interested in learning more about DOOM, the book "Masters of Doom" is an entertaining recollection of how id Software started and how John Romero and John Carmack started their careers.

https://en.wikipedia.org/wiki/Masters_of_Doom

Game Engine Black Book: Doom is also a fantastic read!

https://fabiensanglard.net/gebbdoom/

Looks very interesting, thanks for sharing! The pricing section is very informative btw, congrats to the author for sharing it

Fabien is a Hacker News darling, I'd highly recommend both the DOOM black book and Wolfenstein black book, I have them and love every page. Give him your support!

Masters of Doom is also required reading for any hacker.

If you're interested in this topic, there is probably no better source now than the recent John Romero autobiography Doom Guy

I second that. Romero's autobiography covers Doom's development in detail, well beyond The Masters of Doom. This includes all the games leading up to Doom, which informed their approach. It was a great read.

Anyone know if anyone ever asked Carmack about how he felt about Descent? That was the first 3d game I was exposed to that ever felt like a true 3d experience.

That's probably a better question for Romero. Unless you are interested in Carmack's take on Descent's engine.

I'd love to hear both.

I think Descent is under-appreciated. It was a full 3d world and was released a year or two before Quake.

To my mind, the engine was as solid as Quake. For example it didn't have the misbehaving Z-buffer/intersection issues of Tomb Raider.

Doom helped me out of a crippling fear of hell/damnation that was beat into me by a religious upbringing and I will forever be grateful.

That's beautiful. I'm deeply sorry you had to go through that, from someone raised by a deacon. Hope everything is going OK.

Rip and tear

Actual interview is a Twitch vod on John Romero's channel: https://www.twitch.tv/videos/2000693432

YouTube archive also: https://youtu.be/QvAkaJsvAXs

Seeing the picture of them holding swords when they were young is blowing my mind. I only picture Carmack as an old sage, not as a young ranger.

I still picture him as something like the Encyclopedia Brittanica kid (back from when encyclopedias still came in paper volumes):

https://m.youtube.com/watch?v=lMpgcz6s-eI

Even though he has aged, he still seems like a 90s whiz kid, and that's something every hacker wishes they could pull off in middle age.

More Doom 30-year chat:

https://news.ycombinator.com/item?id=38594405

Some more anecdotes and stuff from earlier today:

Sigil II, a Doom WAD from J.Romero, has been released

https://news.ycombinator.com/item?id=38593248

id Software has an incredibly important legacy.

Not only they revolutionized games, but their decision to open source their game engines has so many implications that it is hard to even begin quantifying their impact.

And it's not only the FPS games that left a mark in history, the 2D platformers were awesome too.

their decision to open source their game engines has so many implications that it is hard to even begin quantifying their impact

What are you thinking of?

As far as I recall, the main benefit has been to developer curiosity but I don't know of much impact beyond that. The games that used Id engines like HL or Call of Duty had to license it anyway right and didn't use the open source versions? I don't recall much of a scene around the open source engines unlike the mod scene that used the official game and assets.

Things like Quake2 running on the Quest uses an engine that I think started off with original source but eh, it's not that significant. Q2 was huge to me at the time but I can't muster the enthusiasm to play it in VR. I look at it briefly and I'm done.

There was Quake II RTX created by Nvidia but again, eh. That and Portal RTX did not make a convincing case for ray tracing. They ran like pigs and didn't look terribly good to me.

The link for anyone interested https://m.twitch.tv/videos/2000693432?desktop-redirect=true

I see John Romero uses the same logitech webcam I do that makes me channel AvE every time I have to yell "focus, you fuck!"

Back story on the weapons in the pic, from Scott Host (creator of Raptor: Call of the Shadows): "Me and Carmack were at the Dallas Renaissance Fair, and we stopped at "Angel Sword" (they make real medieval weapons). Carmack asked "Which sword I should get?" and I said the curvy one. The Axe was 8000 dollars and the sword was 12,000."

Fun little story, at Kansasfest 1992 (the Apple II conference that persists today) I was incredibly young but was roaming the dorms at night between various groups hacking on stuff and begging for underage-beers, when I heard some chatter about some people who had developed an interesting 3D game and promptly received over $800KUSD in shareware fees in just a month, enabling the purchase of fast cars. I ran into those people and saw a brief demonstration of Wolf3D on a plasma-screen laptop, it looked mighty fancy.

The next day, I saw Carmack stick his head into a computer lab where and friend and I were hacking on something, and I said "Hey John! I really liked Wraith! I just beat it!" (Wraith was an 8-bit tiled 2D adventure game that he had released). He smiled and said "Oh, I've gotten a bit better since Wraith..."

Of course by that time, he was about to release Doom. Not to belittle the ray-casting problem of determining which 2D tiles to hide and show in those adventure games, but he had indeed gotten a bit better.

I specifically enjoyed when John Carmack commented that because of its programmability, Quake launched a lot of software development careers, whereas the early network capabilities of DOOM launched a lot of IT professional careers.

It was fun to watch live. Had it on my calendar for a while. I would have liked it more without the moderator I suspect, just a discussion between the Johns.

You can run DooM on anything - including DooM.

https://m.youtube.com/watch?v=c6hnQ1RKhbo

Besides the legendary Masters of Doom book, Romero released his autobiography this year:

The birth of id software – Excerpt from John Romero's autobiography

https://news.ycombinator.com/item?id=36808939