<rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Hacker News: Dave_Rosenthal</title><link>https://news.ycombinator.com/user?id=Dave_Rosenthal</link><description>Hacker News RSS</description><docs>https://hnrss.org/</docs><generator>hnrss v2.1.1</generator><lastBuildDate>Thu, 04 Jun 2026 05:59:58 +0000</lastBuildDate><atom:link href="https://hnrss.org/user?id=Dave_Rosenthal" rel="self" type="application/rss+xml"></atom:link><item><title><![CDATA[New comment by Dave_Rosenthal in "Training our own AI models"]]></title><description><![CDATA[
<p>They say, "our goal here is to improve PostHog as a product for our customers, not to expose or sell models trained on your data" but then don't actually list that as a limitation in the bulleted points.<p>AFAICT this now gives them default permission to train an LLM on your code (as Posthog telemetry data is inextricably tied to your code) use it, and even sell it if they wanted to (as it's not your data anymore, it's their model). Yikes.</p>
]]></description><pubDate>Wed, 27 May 2026 17:44:29 +0000</pubDate><link>https://news.ycombinator.com/item?id=48297747</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=48297747</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=48297747</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "Colored Shadow Penumbra"]]></title><description><![CDATA[
<p>Simple answer: There is no physical basis, it's style<p>Pedantic answer: Unless the light source has different colors on different sides<p>Complex answer: Kind of. Even a linear color fade (from reality) can turn non-linear (and therefore induce color effects) when pushed through a color grading pipeline. So if you count e.g. film emulation as a "physical effect", then yes.</p>
]]></description><pubDate>Thu, 07 May 2026 21:10:34 +0000</pubDate><link>https://news.ycombinator.com/item?id=48055077</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=48055077</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=48055077</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "Extremophile molds are invading art museums"]]></title><description><![CDATA[
<p>The car guys have done it: <a href="https://www.youtube.com/watch?v=stfjVt0AbFU" rel="nofollow">https://www.youtube.com/watch?v=stfjVt0AbFU</a></p>
]]></description><pubDate>Tue, 27 Jan 2026 20:53:53 +0000</pubDate><link>https://news.ycombinator.com/item?id=46786511</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=46786511</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=46786511</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "Try to take my position: The best promotion advice I ever got"]]></title><description><![CDATA[
<p>As a boss-man myself, I’ve seen this “don’t let them take advantage of you” sentiment expressed in many discussions about comp and promotions, but I can’t really say I understand it. Am I just out of touch?<p>As I read it, the article is simply trying to help people understand what kind of work is valuable to a company and therefore what they should focus on to make themselves valuable. I presume that making yourself valuable pays dividends, including promotions! Somehow the idea of going to work and not trying your best because “you’re not getting paid … for that” just feels so cynical and divorced from how I’ve seen successful people grow and make big bucks in tech.<p>(And this is all a bit separate, of course, than the debate about whether staying at a company or job hopping is better for career trajectory.)</p>
]]></description><pubDate>Mon, 05 Jan 2026 22:45:45 +0000</pubDate><link>https://news.ycombinator.com/item?id=46506192</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=46506192</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=46506192</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "This week in 1988, Robert Morris unleashed his eponymous worm"]]></title><description><![CDATA[
<p>RTM was my TA at MIT for a CS/systems engineering course. It took the students until we did an assignment about the worm to realize who he was IIRC. The students thought it was very cool, but even then, as a TA covering the assignment, he didn't really talk about it.</p>
]]></description><pubDate>Tue, 04 Nov 2025 22:40:28 +0000</pubDate><link>https://news.ycombinator.com/item?id=45816709</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=45816709</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=45816709</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "Zip Code Map of the United States"]]></title><description><![CDATA[
<p>Neat visualization. There is a street performer in my town that has them all memorized (and many international zip codes as well) and makes a fun show of it, asking people what zip code they are from and putting them on a map. Sometimes it takes him a second to recall the exact town name but he always knows instantly what city they are close to, helped no doubt by the locality of the mapping. Example video:<p><a href="https://www.youtube.com/watch?v=eSFt38IS0QU" rel="nofollow">https://www.youtube.com/watch?v=eSFt38IS0QU</a></p>
]]></description><pubDate>Wed, 24 Sep 2025 04:00:27 +0000</pubDate><link>https://news.ycombinator.com/item?id=45356148</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=45356148</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=45356148</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "The Fancy Rug Dilemma"]]></title><description><![CDATA[
<p>Sure, let's take a rug as an example. I don't think there is one breakpoint. I think there are a set of axis of quality you invest into, roughly sequentially, as you go up the price scale of objects:<p>- $50 - Something rug-shaped exists<p>- $100 - Durability<p>- $200 - Materials<p>- $500 - Comfort and design<p>- $1000 - Basic craftsmanship<p>- $2000 - Refinement of craft<p>- $5000 - Artistry & identity<p>- $10000 - Tradition<p>- $20000 - Mastery<p>- $50000 - Rarity/historical importance<p>- $100000+ - ?<p>Because most people don't cross-shop $20k rugs and $200 rugs, most people are focused on one or two aspects around their personal budget. The essayist mentioned being amazing by the craftsmanship and artistry (see scale above). A broke college student might just want something that holds up in their dorm room and see what materials it's made out of and comfort as meaningless and abstract. And a billionaire shopping for a rug for their office might take everything other than rarity/historical importance as a given and just be thinking about that.<p>I think there is a large cognitive bias to consider everything you can easily afford "tangible and important improvements" and everything you can't as "abstract"!</p>
]]></description><pubDate>Sat, 23 Aug 2025 15:15:53 +0000</pubDate><link>https://news.ycombinator.com/item?id=44996587</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=44996587</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=44996587</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "FoundationDB: From idea to Apple acquisition [video]"]]></title><description><![CDATA[
<p>We thought of that demo with like a week or two to go before the event when we realized we needed something more visceral than a blinking cursor :)<p>So, it stayed with the world because it went semi viral in some tiny circles. But it didn’t stay with me because I personally learned little from it.<p>The thing that stays with me is all the things I learned spending years trying to implement an API you can describe in ~30 seconds <i>really well</i>. It’s a rare opportunity to be able to go so deep on a problem in a career.</p>
]]></description><pubDate>Thu, 31 Jul 2025 01:01:51 +0000</pubDate><link>https://news.ycombinator.com/item?id=44741311</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=44741311</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=44741311</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "FoundationDB: From idea to Apple acquisition [video]"]]></title><description><![CDATA[
<p>The documentation is woefully out of date, sadly. Despite the code being in active development no one is touching the public docs. Though I don’t know for sure, that limitation was probably written something like 10 years ago.</p>
]]></description><pubDate>Thu, 31 Jul 2025 00:52:16 +0000</pubDate><link>https://news.ycombinator.com/item?id=44741259</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=44741259</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=44741259</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "FoundationDB: From idea to Apple acquisition [video]"]]></title><description><![CDATA[
<p>Ha, well I met Scherer ~30 years ago in a high school math class and we’ve done three companies together, so you could say we’ve known each other for a bit :)</p>
]]></description><pubDate>Wed, 30 Jul 2025 03:39:05 +0000</pubDate><link>https://news.ycombinator.com/item?id=44730705</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=44730705</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=44730705</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "Foundation DB Record Layer SQL API"]]></title><description><![CDATA[
<p>Well, I stand very much corrected since that's me in the video! I forgot that an early version ever made it out into the world.</p>
]]></description><pubDate>Sat, 10 May 2025 00:17:13 +0000</pubDate><link>https://news.ycombinator.com/item?id=43942178</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=43942178</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=43942178</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "Foundation DB Record Layer SQL API"]]></title><description><![CDATA[
<p>It looks like it might be knobs (which can be changed via config file) called MAX_WRITE_TRANSACTION_LIFE_VERSIONS and MAX_READ_TRANSACTION_LIFE_VERSIONS now (defined in ServerKnobs.cpp)? It's in microseconds and probably needs to be synced client and server.<p>I don't know the details know, but it was definitely configurable when I wrote it :) I remember arguing for setting it to a default of 30/60 seconds we decided against as that would have impacted throughput at our default RAM budget. I thought might have been a good tradeoff to get people going, thinking they could tune it down (or up the RAM) if they needed to scale up perf later.</p>
]]></description><pubDate>Fri, 09 May 2025 04:07:19 +0000</pubDate><link>https://news.ycombinator.com/item?id=43933711</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=43933711</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=43933711</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "Foundation DB Record Layer SQL API"]]></title><description><![CDATA[
<p>You might be <i>able to</i>, but are definitely not supposed to. The client is conceptually "part of the cluster".</p>
]]></description><pubDate>Thu, 08 May 2025 16:57:39 +0000</pubDate><link>https://news.ycombinator.com/item?id=43928243</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=43928243</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=43928243</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "Foundation DB Record Layer SQL API"]]></title><description><![CDATA[
<p>There have been some 3rd party toy projects in the past years, but pretty sure nothing was ever released by FoundationDB/Apple relating to SQL (until this additional SQL interface on the Apple "record layer").</p>
]]></description><pubDate>Thu, 08 May 2025 16:54:35 +0000</pubDate><link>https://news.ycombinator.com/item?id=43928198</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=43928198</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=43928198</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "Foundation DB Record Layer SQL API"]]></title><description><![CDATA[
<p>Thanks for the insight. A $XX million exa-data system is no doubt impressive :)<p>> Another big problem I found with modeling real apps was the five second transaction timeout. This is not, as you might expect, a configurable value. It's hard-coded into the servers and clients. This turns into a hugely awkward limitation and routinely wrecks your application logic and forces you to implement very tricky concurrency algorithms inside your app, just to do basic tasks. For example, computing most reports over a large dataset does not work with FoundationDB because you can't get a consistent snapshot for more than five seconds!<p>I'm pretty sure that the 5-second transaction timeout is configurable with a knob. You just need enough RAM to hold the key-range information for the transaction timeout period. Basically: throughput * transaction_time_limit <= RAM, since FDB enforces that isolation reconciliation runs in memory.<p>But, the other reason that 5 seconds is the default is that e.g. 1 hour read/write transactions don't really make sense in the optimistic concurrency world. This is the downside of optimistic concurrency. The upside is that your system never gets blocked by bad-behaved long-running transactions, which is a serious issue in real production systems.<p>Finally, I think that the current "Redwood" storage engine does allow long-lived read transactions, even though the original engine backing FDB didn't.</p>
]]></description><pubDate>Thu, 08 May 2025 16:50:46 +0000</pubDate><link>https://news.ycombinator.com/item?id=43928135</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=43928135</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=43928135</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "Foundation DB Record Layer SQL API"]]></title><description><![CDATA[
<p>FoundationDB's original promise was to combine a distributed storage engine with stateless layers on top to expose a variety of useful data structures (including SQL). The company was acquired before it could release the layers part of that equation. Apple open-sourced the core storage engine a few years later so FDB has kind of had a second life since then.<p>In that second life, the vast majority of the powerful databases around the industry built on FoundationDB have been built by companies making their own custom layers that are not public. This release is cool because it's a rare case that a company that has built a non-trivial layer on top of FDB is letting that source code be seen.<p>The group to which the FoundationDB storage engine itself appeals is fairly narrow--you have to want to go deep enough to build your own database/datastore, but not so deep to want to start from scratch. But, for this group, there is still nothing like FoundationDB in the industry--a distributed ACID KV store of extreme performance and robustness. So, yes, it's still the hotness in that sense. (As others have mentioned, see e.g. Deepseek's recent reveal of their 3FS distributed filesystem which relies on FDB.)</p>
]]></description><pubDate>Thu, 08 May 2025 00:32:36 +0000</pubDate><link>https://news.ycombinator.com/item?id=43921860</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=43921860</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=43921860</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "Variable duty cycle square waves with the Web Audio API"]]></title><description><![CDATA[
<p>I was curious to see how audible square wave duty cycle would be (I figured not much) but sadly the audio examples are clearly broken on this page--choosing the same one multiple times gives totally different sounds.</p>
]]></description><pubDate>Mon, 07 Apr 2025 19:50:06 +0000</pubDate><link>https://news.ycombinator.com/item?id=43615207</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=43615207</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=43615207</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "Apple needs a Snow Sequoia"]]></title><description><![CDATA[
<p>Huh, I was actually on this page a few years ago, but iOS and MacOS quality has been super solid for me this past year. Anyone else feel this way? Judging by the nodding comments maybe I’m just the outlier?</p>
]]></description><pubDate>Fri, 28 Mar 2025 00:22:22 +0000</pubDate><link>https://news.ycombinator.com/item?id=43499871</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=43499871</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=43499871</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "Happy 20th birthday, Y Combinator"]]></title><description><![CDATA[
<p>You were talking to a slightly earlier company--this was post Viaweb.</p>
]]></description><pubDate>Wed, 12 Mar 2025 17:04:33 +0000</pubDate><link>https://news.ycombinator.com/item?id=43345336</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=43345336</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=43345336</guid></item><item><title><![CDATA[New comment by Dave_Rosenthal in "Happy 20th birthday, Y Combinator"]]></title><description><![CDATA[
<p>I worked with pg in a three-person startup in a basement in Harvard square just before he started YC. I was an undergrad at MIT and met him after arguing with rtm (who was a TA for my class) about TCP backoff. It was called Aspra and we were trying to build an app development platform for mobile phones. The idea was that you could build an application that could "render" to either an IVR system, for dumb phones, or the kind of web page that a Motorola "smartphone" of the day could view. Ahead of its time, like Paul. It didn't go far, and not long after he started YC. Good thing he did, for the industry and many of the folks here! Anyway, the "20 years" got my attention because I didn't feel that old, and thought someone might like the little story.</p>
]]></description><pubDate>Wed, 12 Mar 2025 02:20:22 +0000</pubDate><link>https://news.ycombinator.com/item?id=43339316</link><dc:creator>Dave_Rosenthal</dc:creator><comments>https://news.ycombinator.com/item?id=43339316</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=43339316</guid></item></channel></rss>