Battle Drones - a vibe coded RTS with audio-based multiplayerMy latest vibe coded game experiment is a Command & Conquer style RTS (Real Time Strategy) game called Battle Drones ( play it here ). Unlike my previous experiments , this one is actually fun to play . I'm somewhat embarrassed to admit thaSWSimon W2026/10/21 03:34
Hello Python 3.15, goodbye 3.10, and now I can use 3.11Python 3.15 is here ! Here's the essential What's new in Python 3.15 guide, this year curated by 3.14 and 3.15 release manager Hugo van Kemenade. As someone who builds open source software that works in every supported Python version, I getSWSimon W2026/10/13 02:15
A new feature for my blog, built using my voiceI shipped a new feature for my blog today: the Newsletters page, which offers an index of all of the newsletters I've sent out, both my free weekly Substack and my monthly sponsors-only updates. I built the feature almost entirely using my SWSimon W2026/10/09 20:54
Claude Haiku 5.5As previously promised , here's Anthropic's new fast, low cost model: Introducing Claude Haiku 5.5 . The previous Haiku, 4.5, was very much showing its age. It came out almost a year ago , and was priced at $1/million input and $5/million oSWSimon W2026/10/08 04:56
SWWe're going to need default hard budget caps on pretty much everythingHere's a product feature which the world is going to need a whole lot more of over the coming months and years: default hard budget caps . I'm talking about the feature of pay-by-usage services and APIs that lets you say "after $X/month, cuSWSimon W2026/10/04 07:34
SWOpenAI DevDay 2026 live blogI'm at OpenAI DevDay today, in Fort Mason, San Francisco. Same as last year I'll be live blogging the keynote and some other notes during the day. OpenAI gave me a free ticket and a seat in the "creator" area for the keynote. You are only sSWSimon W2026/09/29 23:55
2026 in LLMs (so far)On Friday I gave the closing keynote at the WeAreDevelopers World Congress North America in San Jose. I tied together the key trends from the past year into a chronological exploration of everything that happened in 2026. The video is on YoSWSimon W2026/09/28 07:54
Claude Opus 5.5, GPT-6 Sol, GPT-6 Luna, and a new price warYesterday was Grok 4.7 ( pelicans ) and MiMo v2.6 Flash/Pro ( more pelicans ). Today Anthropic released Claude Opus 5.5 , and around an hour later OpenAI released GPT-6 Sol and GPT-6 Luna . It's going to take a while to get a good read on aSWSimon W2026/09/23 07:46
SWJev introduces a new shape of LLM - System One, aka Decision ModelsLast week TypeSafe AI unveiled Jev , their first example of a new category of model that they are calling "System One models" (I'm with Maggie Appleton, I think "decision models" is a better name for these). Jev is an interesting variant onSWSimon W2026/09/22 07:09
Generating running routes with GPT-6 Astra and ChatGPT WorkHere's a neat thing I had ChatGPT Work with GPT-6 Astra (Max) do this morning: I live at <my address>. Figure out 5K and 10K running routes from me that loop from my house. Use OSM data. It worked for 27 minutes and produced exactly what I'SWSimon W2026/09/13 07:56
SWOpenAI agents attacked RubyGems back in MayOpenAI agents carried out an undisclosed attack on RubyGems is a new bombshell report from Spencer Kitts, Thomas Larsen, and Sydney Von Arx - three of the four authors of the report on the agent attack on disused wikis ( previously ) last wSWSimon W2026/09/12 08:42
SWSome thoughts on the Navier–Stokes Millennium Prize ProblemOn the Navier–Stokes Millennium Prize Problem introduces an impressive result from OpenAI, who used an unreleased model to produce a resolution to the Navier–Stokes existence and smoothness problem , one of the seven Millennium Prize ProbleSWSimon W2026/09/09 07:55
The Pelican comparison grid for Astra is pretty interestingI got access to GPT-6 Astra this afternoon, so naturally I used it to generate SVGs of pelicans riding bicycles - at low, medium, high, xhigh and max reasoning levels (Astra doesn't support reasoning=none). Then I rendered those pelicans inSWSimon W2026/09/05 07:59
SWOpenAI's rogue agents were caught communicating via public wikisHere we go again... Discovery of a new OpenAI agent message board by Sydney Von Arx, Cormac Slade Byrd, Spencer Kitts, and Thomas Larsen describes the latest accidental cyberattack by models being trained by OpenAI. This time it was agents SWSimon W2026/09/05 01:38
Claude's new system prompt really doesn't want to reproduce song lyricsAnthropic publish the system prompts for their Claude consumer applications ( Claude.ai and the Claude mobile apps - sadly not for Claude Cowork or Claude Code). I love that they do this, and that they share not just the current prompts butSWSimon W2026/09/02 22:16
Claude Fable 5.1 made me a really nice animated pelicanToday is Claude Fable (and Mythos) 5.1 day . Anthropic say that Fable 5.1 "sets a new standard for coding, knowledge work, and long-running problem-solving tasks". Their announcement spends a notable amount of time on scientific research, bSWSimon W2026/09/02 07:57
Understanding ChatGPT WorkOpenAI announced ChatGPT Work on July 9th, and have been furiously iterating on it ever since. It is an extraordinarily confusing and very powerful product. Here's what I've figured out about it so far. ChatGPT Work is actually two productsSWSimon W2026/08/31 07:59
SWConceptual integrity and counting lines of codeLast week I recorded an episode of the Talking Postgres podcast with Claire Giordano on the subject of "How AI is changing software development". We had a really great conversation. Here are a couple of my highlights from a lightly edited tSWSimon W2026/08/20 06:46
Qwen 3.8 27B is excellent, but it defaults to wildly overthinking thingsFriday's big release was Qwen 3.8 27B , an Apache 2 licensed 27B parameter vision-capable LLM from Alibaba's Qwen research lab. I've been looking forward to this one: 27B is an excellent size for running a model on a reasonably specced laptSWSimon W2026/08/17 06:00
SWNow we have a timeline of the OpenAI accidental attack against Hugging FaceOpenAI gave a last-minute presentation at the Black Hat security on Wednesday about "the Hugging Face Incident" ( previously on this blog). The video was published yesterday. It's short and information dense and well worth watching, in partSWSimon W2026/08/08 07:55