More of my notes on DeepSeek V4 – the really big news is the pricing: both DeepSeek-V4-Flash and DeepSeek-V4-Pro are the cheapest models in their categories while benchmarking close to the frontier models from other providers https://
simonwillison.net/2026/Apr/24/de
epseek-v4/
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@simonw
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DeepSeek V4 Offers Cheapest Models Near Frontier Performance
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DeepSeek Flash vs Pro Pelican Image Generation via OpenRouter
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These pelicans are kind of angry looking! Left is deepseek-v4-flash, right is deepseek-v4-pro – both generated using OpenRouter via my LLM tool
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Newsletter Covers GPT-4.5, ChatGPT Images, Qwen3 and Agentic Patterns
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This week's edition of my email newsletter features 4 pelicans riding bicycles, 1 possum on an e-scooter, up to 5 raccoons with ham radios hiding in crowds, 5 blog posts, 8 links, 3 quotes and a new chapter of my Agentic Engineering Patterns guide https://
simonw.substack.com/p/gpt-55-chatg
pt-images-20-qwen36-27b
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LiteParse Web Version Built with Claude Code in One Hour
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That browser version of LiteParse is available here: https://
simonw.github.io/liteparse/ Detailed notes on how I built it using Claude Code (running for an hour) on my blog: https://
simonwillison.net/2026/Apr/23/li
teparse-for-the-web/
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Browser Version of LiteParse PDF Text Extraction Tool
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LiteParse is really neat! It does a great job of extracting text from annoying layouts in PDFs (multiple columns for example) It's only available as a Node.js CLI app, so I vibe-coded up this version that runs in a browser
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New llm-openai-via-codex Plugin for GPT-5.5 Released
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You might enjoy my new llm-openai-via-codex plugin! https://
simonwillison.net/2026/Apr/23/gp
t-5-5/#llm-openai-via-codex
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GPT-5.5 Available via Codex API Backdoor for Image Generation
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GPT-5.5 may not be in the official OpenAI API… but it's available via the apparently approved-of Codex API backdoor So I used that to make these pelicans (default and xhigh)! https://
simonwillison.net/2026/Apr/23/gp
t-5-5/
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Codex Used for Security Reviews of AI-Generated Code
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I've been previewing this in Codex for a few weeks – it's very good!
— Simon Willison (@simonw) 23 avril 2026
Had some great results from it having it run security reviews against code written using other models https://t.co/MHVbOboODqI've been previewing this in Codex for a few weeks – it's very good! Had some great results from it having it run security reviews against code written using other models
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Creator of the Term Prompt Injection Shares Its Origin
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I named prompt injection after SQL injection a few years ago
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Promoting Typeless.com for AI-driven Automation and No-Code Solutions
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They have the Falcon series, right? I remember those being quite good open weight models a couple of years ago