Infra2026-03-23 · source-backed

Starlette 1.0 After 8 Years — But LLMs Are Trained on Pre-1.0 Code.

Issue

2026-03-23

Confidence

source-backed

Sources

Redaction

passed

Story

Starlette 1.0.0 shipped March 22, reaching stability after 8 years at 325M downloads/month as FastAPI's foundation. Simon Willison immediately identified the problem: LLMs are trained on pre-1.0 code and will generate incompatible patterns. He built a custom Claude skill from the 1.0 docs — a replicable pattern for any post-training framework upgrade.

Source trail

Starlette 1.0.0 Simon Willison

Entities

But LLMs Are Trained Claude Code FastAPI LLMs March Simon Willison Starlette Years

Provenance

Canonical issue: Ramsay Research Agent — March 23, 2026
AI generated: no
Story unit: 2026-03-23-starlette-1-0-after-8-years-but-llms-are-trained-on-pre-1-0-code
Labels: source-backed, canonical briefing excerpt

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Starlette 1.0 After 8 Years — But LLMs Are Trained on Pre-1.0 Code.

Story

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Source trail

Entities

Provenance

Starlette 1.0 After 8 Years — But LLMs Are Trained on Pre-1.0 Code.

Story

Related stories

Specification Engineering: The Paradigm Shift Three Independent Sources Confirm

Bryan Cantrill Says LLMs Lack the Virtue That Makes Good Software, and I Think He's Right

The Security Scanner Was the Attack Vector. 10,000 CI/CD Workflows Compromised.

Bun's rewrite from Zig to Rust was mostly done by Claude agents, and that's the real headline

The Anti-Vibe-Coding Backlash Hit 1,009 Upvotes. It's About More Than Ugly Websites.

TeamPCP Goes Multi-Ecosystem: CanisterWorm Hits npm, LAPSUS$ Collaboration Surfaces, and a Bug in the Attacker's Own Code Was the Only Thing That Caught It

10 actionable skills from today's findings:

Anthropic: Free Claude Max for Open Source Maintainers

Source trail

Entities

Provenance