Complete Timeline

13 Events — Full Chronology

From the first source map leak in 2025 to the congressional inquiry. Every event sourced from major outlets.

precursor

incident

aftermath

2025-02

First Source Map Leak (v1)

Claude Code previously leaked source via npm source maps. This March 2026 incident is the second time.

→ Pattern of build pipeline vulnerability — not a one-off.

2025-12

Anthropic Acquires Bun

Anthropic acquires the Bun JavaScript runtime. Claude Code is rebuilt on top of Bun, which generates source maps by default.

→ Sets the stage: Bun's default source map behavior becomes the root cause.

2026-03-11

Bun Source Map Bug Filed

Bug oven-sh/bun#28001 filed: source maps served in production mode despite Bun docs saying they should be disabled. Issue remains open.

→ Known bug in Anthropic's own acquired toolchain — unfixed for 20 days before the leak.

2026-03-21

OpenCode Cease-and-Desist

Anthropic sends legal threats to OpenCode, forcing removal of built-in Claude authentication. Third-party tools were using Claude Code's internal APIs.

→ Developer community backlash — 'Anthropic is acting like a gatekeeping megacorp.'

2026-03-24

Mythos / Capybara Model Leak

Fortune discovers ~3,000 Anthropic files in a publicly accessible data cache, including draft blog post about upcoming model Mythos/Capybara.

→ First leak in sequence — next-gen model plans exposed. Described as 'a step change.'

2026-03-31 04:23 ET

Source Map Discovered

Chaofan Shou (@Fried_rice), intern at Solayer Labs, discovers the .map file in Claude Code v2.1.88 npm package. Posts download link on X.

→ 59.8 MB source map → zip archive on Anthropic's Cloudflare R2 bucket → 512K lines exposed.

2026-03-31 ~06:00

GitHub Mirrors Explode

Code mirrored, forked 41,500+ times. claw-code (clean-room Python rewrite) hits 50K stars in ~2 hours — likely fastest-growing GitHub repo ever.

→ Irrecoverable spread. Anthropic issues 8,000+ DMCA takedowns, accidentally hitting their own repo forks.

2026-03-31 00:21–03:29 UTC

Concurrent npm Supply Chain Attack

Malicious axios versions (1.14.1, 0.30.4) with embedded RAT published to npm — unrelated but coinciding. Contains plain-crypto-js trojan.

→ Users who npm-installed Claude Code during this window may be compromised. Anthropic recommends native installer.

2026-03-31 PM

Anthropic Official Statement

"No sensitive customer data or credentials were involved or exposed. This was a release packaging issue caused by human error, not a security breach."

→ Boris Cherny: 'It's never an individual's fault. It's the process, the culture, or the infra.'

2026-04-01

/buddy Launches as April Fools Feature

Anthropic officially launches the Buddy companion pet system, confirming it as their April Fools 2026 feature. Available in v2.1.89+.

→ Turned a leaked feature into a viral marketing moment. Community creates buddy previewer tools within hours.

2026-04-01

Deep Analysis Wave

Engineering blogs (Layer5, Engineer's Codex, Alex Kim, VentureBeat) publish detailed architectural breakdowns of KAIROS, autoDream, ULTRAPLAN, Coordinator Mode, and anti-distillation.

→ Feature flags and product roadmap become public knowledge — competitors get free engineering education.

2026-04-02

Congressional Inquiry

Rep. Josh Gottheimer formally presses Anthropic on security lapses. Zscaler discovers trojanized GitHub repos disguised as Claude Code source.

→ Event escalates from technical incident to regulatory concern + active malware campaign.

2026-04-02

IPFS Upload

User 4nzn uploads stripped version to IPFS with telemetry removed, guardrails removed, and all experimental features unlocked.

→ Whether DMCA can reach IPFS content is an unresolved legal question.