A Runaway Build Dies Very Differently Under cgroup Than Under ulimit
Claude Code v2.1.233 added opt-in memory cgroup support for Bash tool commands on Linux. Capping virtual address space with ulimit -v and capping physical memory with a cgroup produce completely different failures — and only one of them lets your Node build start at all.
Tracking Multi-Step Work in Claude Code Now That the Todo Tools Are Off by Default
Since Claude Code v2.1.233, TodoWrite and the Task tools are left out on the newer models. Here are the three branches to check before you set the opt-in variable, the PostToolUse ledger I put in their place, and the measured point where that ledger quietly corrupts under parallel agents.
If You Walk Away While Claude Code Is Running, Turn On Remote Control First
Hand off a long task, step out, and you often come back to a session that stalled at the very first approval prompt. Remote Control lets you reach the Claude Code session running on your own machine from your phone or a browser. Here is how to set it up and what to know before you rely on it.
The Connection That Dies Mid-Thought Is Being Killed by Your Relay, Not the Upstream
Put a proxy or Worker in front of Claude Code and long thinking pauses start dying. The cause is neither the model nor the upstream — it is your relay holding the byte stream. Six relay behaviors compared side by side, plus how to verify yours before it ships.
One generated file outweighed all 70 hand-written source files, so I redrew what Claude Code may read
I profiled a repository I actually run to see which areas consume the most context. Here is what I found, the deny rules I settled on, how search selectivity changes the math, and the options I considered but rejected.
When Paying Users Still See Ads: Collapsing the Ad-Free Check Into One Place
A user who paid to remove ads still sees them. The cause is rarely a missing flag — it is a check that lives in too many places. Here is how I inventoried every ad call with Claude Code and folded the decision into a single gate.
The Same rm -rf Was Recoverable in Ten Places and Unrecoverable in Five — Measuring Reversibility Before Auto Mode Becomes the Default
Auto mode becomes the default on Pro, Max and Team from August 14. It stops on operations judged irreversible, destructive, or outward-facing — but reversibility turned out to be a property of state, not of commands. Here is the probe and the measurements.
One Transient 401 Replaced My Long-Lived Token — Giving Credentials a Provenance Field
A shared credential file can lose its long-lived token to a single transient 401. I injected exactly one 401 into a 24-worker fleet, measured the blast radius, and compared a provenance guard against full isolation.
Same Content, Different SHA-256: Making Pinned Plugin Archives Reproducible
Plugins can now be installed from an HTTPS zip with an optional SHA-256 pin. Building the same tree twice produced archives that differed in 50 bytes out of 22,669 and broke the pin every time. Here is the byte-level measurement and a packaging recipe that produced an identical hash 20 times out of 20.
The Write Your Permission Mode Never Stops — Auditing an Agent-Scoped PreToolUse Gate Across 150 Payloads
Workflow subagents auto-approve file edits regardless of your session permission mode. I measured the remaining boundary — an agent_id-scoped PreToolUse hook — across 150 payloads, found 54 silent pass-throughs, and rebuilt it to fail closed.
The Skill Call That Returned Nothing — Pinning Down Name Resolution Before an Unattended Run
A skill whose name collides with a built-in terminal command may never resolve in a non-interactive session. Here is a preflight that builds the effective-name table before launch, plus the measured run where the checker itself silently skipped two entries.
Passing the Request, Not the Secret — Where Sandbox Credential Masking Works and Where Substitution Breaks
Claude Code's sandbox credential masking lets processes read sentinel values while a proxy swaps in the real secret at send time. I rebuilt it as a minimal proxy and measured which auth schemes survive the swap, which break, and what happens when the secret rides in the body.