Opus 5 halves Fable 5's price — and vibe-coded apps got hacked again

Hey — Big model week. Anthropic dropped a new flagship four days ago and it's already the default in my terminal. On the other end of the spectrum, the vibe-coding security story that keeps not going away kept not going away. Here's what mattered. ## This Week in AI Coding **Claude Opus 5 shipped July 24 — and it's now Claude Code's default model.** Same $5/$25-per-Mtok price as Opus 4.8, but it more than doubles Opus 4.8's score on Frontier-Bench v0.1 (43.3%, ahead of Fable 5's 33.7%) and scores 3x the next-best model on ARC-AGI 3. It lands within 0.5% of Fable 5's peak on CursorBench 3.2 at half the cost per task. Claude Code 2.1.219 made it the default the same day it shipped. If you've been defaulting to Fable 5 for coding work, worth checking whether Opus 5 gets you there for less. **Google shipped Gemini 3.6 Flash on July 21 and teased Gemini 4.** New default in the Gemini family: 1M context, $1.50/$7.50 per Mtok, ~17% fewer output tokens than 3.5 Flash while scoring higher on coding and computer-use benchmarks. It's already live in GitHub Copilot's model picker. Google didn't say much about Gemini 4 beyond the tease — read into that what you want. **Moonshot's Kimi K3 ships its open weights July 27 — a 2.8-trillion-parameter model that already beat Claude Fable 5 on Arena.AI's Frontend Code Arena.** It's a mixture-of-experts design that activates only 16 of 896 experts per token, and it leads every model on SWE Marathon and Program Bench, trailing only GPT-5.6 Sol on Terminal-Bench 2.1. If you run local or self-hosted inference, this is the one landing this weekend. **Theori's Xint.io platform found 434 exploitable vulnerabilities across AI-built apps on July 22 — 196 of them in brand-new applications.** Meanwhile Lovable, the $6.6B vibe-coding platform, left a BOLA vulnerability open for 48 days after closing the bug bounty report without escalating it. The pattern isn't "AI writes bad code sometimes." It's "nobody's reviewing what ships." If you're vibe-coding anything customer-facing, that review is still your job, not the model's. **AI Engineer is LinkedIn's #1 fastest-growing US job for the second year running, while general software engineering postings sit roughly 49% below the 2020 baseline.** ML/AI-specific roles are up about 59% over that same window, and "Agentic AI" postings are up 587% year over year. The bar hasn't dropped — it's moved. If your resume doesn't say "agents" somewhere, it might be time. ## What We Shipped Ops-heavy week here, not launch-heavy. Cleaned up four dangling Supabase projects (~$12/mo saved, verified nothing was still pointed at them), stood up a v2 weekly portfolio digest with permanent priority-ranking so I stop re-litigating the same triage questions every week, and moved Johnny (the JaaS AI co-founder) onto subscription-CLI auth. Honest note: the YouTube pipeline is still stuck — render backlog grew to 106 this week while I kept drafting scripts (EP193-195 queued) instead of clearing it. That's the real next fire, not a new thing to announce. ## Tool of the Week **Kimi K3.** Not the smartest model out — Opus 5 and Fable 5 both beat it on raw intelligence — but it'll be the best coding model you can run without a subscription once the weights land July 27. Modified MIT license, 1M context, native vision. Worth a slot in your local eval harness even if it doesn't become your daily driver. ## Quick Links - [Anthropic: Introducing Claude Opus 5](https://www.anthropic.com/news/claude-opus-5) - [9to5Google: Gemini 3.6 Flash launch details](https://9to5google.com/2026/07/21/gemini-3-6-flash-launch/) - [VentureBeat: Moonshot AI releases Kimi K3](https://venturebeat.com/technology/chinas-moonshot-ai-releases-kimi-k3-the-largest-open-source-model-ever-rivaling-top-u-s-systems) - [TechCrunch: Anthropic launches Opus 5](https://techcrunch.com/2026/07/24/anthropic-launches-opus-5/) — Guy More at [endofcoding.com](https://endofcoding.com) · [vibecodingebook.com](https://vibecodingebook.com) · [llmhire.com](https://llmhire.com) · [cyberos.dev](https://cyberos.dev) · YouTube [@endofcoding](https://youtube.com/@endofcoding)