Matins

Special report

The changelog,
charted.

We read the Claude Code changelog most mornings, and eventually got curious what all of it looks like at once. So we parsed the lot: every release from 0.2.21 to 2.1.176, every logged change across 437 days, counted, sliced, and drawn.

Numbers run through 13 Jun 2026

319
releases
3,446
logged changes
437
days
51,996
words of release notes
0.x 37 releases · 82 changes 2 Apr 2025 to 21 May 2025
1.x 82 releases · 266 changes 22 May 2025 to 26 Sep 2025
2.x 200 releases · 3,098 changes 29 Sep 2025 to 13 Jun 2026
01

Half of everything is a fix

Take the first word of all 3,446 changes ever shipped and a single verb dominates. For every change that adds, roughly 4.3 fix. The changelog is, by weight, a repair log.

First word of every change entry, 0.2.21 to 2.1.176.

02

The velocity explosion

The pace did not creep up, it detonated. Through most of 2025 a release carried 2 to 4 changes. By spring 2026 the average release carried 25, and May 2026 alone shipped 675 changes. Part of that is a chattier changelog, most of it is a faster team.

0 0 200 8 400 16 600 24 800 32 Apr 25May 25Jun 25Jul 25Aug 25Sep 25Oct 25Nov 25Dec 25Jan 26Feb 26Mar 26Apr 26May 26Jun 26 675 changes ■ changes shipped per month ● changes per release (right scale)

Changes per month (bars, left scale) and average changes per release (line, right scale). The quiet notch before 2.1.0 is the December holiday freeze.

03

The shipping calendar

Every day since the changelog began, one cell each. Darker means more releases that day. Hover anything.

Apr 25May 25Jun 25Jul 25Aug 25Sep 25Oct 25Nov 25Dec 25Jan 26Feb 26Mar 26Apr 26May 26Jun 26 MWF
quiet 4+ releases

The longest silence: 19 days, 19 Dec 2025 to 7 Jan 2026, broken by 2.1.0 and its record 109 changes. The lone dark column on 2 Apr 2025 is the changelog being born: 17 historical versions backfilled with one date stamp.

04

Never on a Sunday

Wednesday is release day. Sunday is sacred: just 3 Sunday releases in 15 months, and every one of them reads like an emergency.

0 40 80 34 Mon 51 Tue 65 Wed 58 Thu 62 Fri 29 Sat 3 Sun

Releases by weekday, backfill day excluded.

2.0.61 · 7 Dec 2025

Reverted VSCode support for multiple terminal clients due to responsiveness issues.

2.1.4 · 11 Jan 2026

Added CLAUDE_CODE_DISABLE_BACKGROUND_TASKS environment variable to disable all background task functionality including auto-backgrounding and the Ctrl...

2.1.87 · 29 Mar 2026

Fixed messages in Cowork Dispatch not getting delivered

All 3 Sunday releases, in full.

05

What breaks

The words that keep coming back. "Hang" appears in more changes than "Windows" does. The fight against the flickering terminal got its own environment variable.

Changes whose text contains each failure word.

06

The cost of speed

The word "regression" tracked the shipping rate almost perfectly: roughly one mention a month through 2025, then climbing as the velocity took off. Fast has a price, and the changelog pays it in public.

0 6 12 Apr 25May 25Jun 25Jul 25Aug 25Sep 25Oct 25Nov 25Dec 25Jan 26Feb 26Mar 26Apr 26May 26Jun 26

Changes mentioning "regression", per month.

07

A timeline of big ideas

When each load-bearing concept first entered the changelog, and how much ink it has taken up since.

  1. MCP 0.2.31 · 2 Apr 2025 · 255 mentions
  2. hooks 1.0.38 · 30 Jun 2025 · 160 mentions
  3. subagents 1.0.41 · 3 Jul 2025 · 97 mentions
  4. worktrees 1.0.120 · 19 Sep 2025 · 71 mentions
  5. plugins 2.0.12 · 9 Oct 2025 · 205 mentions
  6. skills 2.0.20 · 16 Oct 2025 · 126 mentions
  7. sandboxing 2.0.24 · 20 Oct 2025 · 44 mentions
  8. workflows 2.0.35 · 6 Nov 2025 · 21 mentions
  9. background tasks 2.0.45 · 18 Nov 2025 · 20 mentions
  10. LSP 2.0.74 · 19 Dec 2025 · 20 mentions
  11. routines 2.1.2 · 9 Jan 2026 · 2 mentions
  12. teammates 2.1.33 · 6 Feb 2026 · 19 mentions
  13. remote control 2.1.53 · 25 Feb 2026 · 52 mentions
  14. /insights 2.1.101 · 10 Apr 2026 · 4 mentions

First changelog mention. Concepts older than 2 Apr 2025 surface on the backfill date.

08

The vocabulary

126 distinct configuration flags and 101 distinct slash commands have appeared in release notes. These are the ones that come up the most.

Flags & env vars 126 distinct

NO_FLICKER8
ANTHROPIC_BASE_URL7
CLAUDE_CODE_DISABLE_EXPERIMENTAL_BETAS5
CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC4
CLAUDE_PLUGIN_ROOT4
OTEL_LOG_TOOL_DETAILS4
ANTHROPIC_API_KEY3
ANTHROPIC_AUTH_TOKEN3
ANTHROPIC_DEFAULT_OPUS_MODEL3
ANTHROPIC_DEFAULT_SONNET_MODEL3

Slash commands 101 distinct

/model39
/plugin30
/resume25
/config21
/doctor19
/context17
/usage16
/clear15
/rename15
/effort14

The full league table

09

Grep it yourself

Search every change ever logged. Live, in your browser, regex welcome.

The full changelog loads on your first search (about 400 KB).

10

Records & oddities

Biggest release

2.1.0

109 changes on 7 Jan 2026, the day the holiday freeze broke.

Busiest real day

7 releases

24 Jun 2025: 1.0.28, 1.0.29, 1.0.30, 1.0.31, 1.0.32, 1.0.33, 1.0.34.

Longest change note

382 chars

"Added worktree.baseRef setting (fresh | head) to choose whether --worktree, EnterWorktree,..." (2.1.133)

Shortest change note

"Minor bugfixes"

14 characters, 2.0.69. It said what it said.

Pure boilerplate releases

3 of 319

Releases saying only "bug fixes and reliability improvements". Unusually honest, as changelogs go.

Average change note

107 chars

Across all 3,446 entries. Early notes were terse, modern ones are short essays.

Methodology

Source: the official Claude Code CHANGELOG.md, via the archive we keep of it. A "change" is one bullet in a release's notes. Mention counts are changes whose text contains the word, case-insensitive. Versions published before 2 Apr 2025 all carry that date, the day the changelog was first created and backfilled; that day is excluded from weekday and busiest-day records. Dates for later versions are the day the archive first saw them, accurate to about a day. Figures run through 13 Jun 2026; we refresh the page from time to time.