100 added, 1 removed. Audit B to A.
- CLAUDE.md
+ # mirrord
+
+ ## Project Overview
+
+ mirrord is a tool that lets developers run local processes in the context of their Kubernetes cloud environment.
+
+ ### Core Crates
+
+ - `mirrord-layer`: gets loaded into the user's process via `LD_PRELOAD`/`DYLD_INSERT_LIBRARIES`. Intercepts libc
+ calls (files, networking, DNS, env, ...) and turns them into protocol messages sent to intproxy.
+ - `mirrord-intproxy`: sits between the layers and the agent. Matches requests to responses, handles reconnects,
+ and routes messages to the right feature proxy.
+ - `mirrord-agent`: runs in the Kubernetes cluster in the target pod's context and network namespace. Does the actual
+ I/O work requested by the layers.
+ - `mirrord-protocol`: defines the shared messages (`ClientMessage`, `DaemonMessage`) sent between
+ layer/intproxy/agent.
+ - `mirrord-config`: config types and validation. Used by the CLI, layer, and intproxy to decide what features are
+ enabled and what target to use.
+
+ ## Command Reference
+
+ ### Compiling
+
+ ```bash
+ # check the entire workspace at once
+ # use when a change spans multiple crates
+ cargo check --all-targets --keep-going
+
+ # layer and cli bundled with the new layer
+ cargo xtask build-cli
+
+ # standalone cli bundled with a pre-built layer
+ cargo check -p mirrord --keep-going
+
+ # layer + shims + universal binary on macos
+ cargo xtask build-layer
+
+ # standalone layer
+ cargo check -p mirrord-layer --keep-going
+
+ # intproxy
+ cargo check -p mirrord-intproxy --keep-going
+
+ # agent (Linux only)
+ cargo check -p mirrord-agent --target x86_64-unknown-linux-gnu --keep-going
+ ```
+
+ Use `cargo check -p <crate> --keep-going` to surface all errors at once rather than stopping at the first.
+
+ ### Testing
+
+ ```bash
+ # integration tests
+ # requires building the cli first with `xtask build-cli`
+ cargo xtask test-integration
+
+ # filtered integration tests
+ cargo xtask test-integration -- outgoing_udp --nocapture
+
+ # unit tests (cargo test)
+ cargo xtask test-ut
+
+ # filtered unit tests
+ cargo xtask test-ut -- resolve_url_happy_path -- --nocapture
+ ```
+
+ ### Styling
+
+ ```bash
+ # Formatting
+ cargo fmt
+
+ # Linting
+ cargo clippy --all-targets -- --deny warnings
+ ```
+
+ ## Simplicity and Reuse
+
+ mirrord is actively maintained by dozens of people, it is not a greenfield project. When adding or changing things,
+ maximize simplicity. Reuse existing abstractions and codepaths instead of introducing new ones. Every new path is
+ something someone has to understand, maintain, and keep compatible.
+
+ ## Comments and Documentation
+
+ Don't write comments explaining what code does, the code should speak for itself. Instead, focus on _why_ something
+ exists: doc comments that explain the problem a function or struct solves and how it fits into the bigger picture are
+ far more valuable than ones that restate the type signature. Module-level doc comments that give a high-level overview
+ of what a file is responsible for are also very helpful, as they give readers the context to understand the code below.
+ mirrord has a lot of moving pieces and stability is critical, so document tricky or non-obvious behavior clearly.
+
+ When changing how something works, don't leave comments like "this replaces how X used to do it" just document the new
+ behavior directly.
+
+ ## Style Guideline
+
+ - Keep imports at file top (no function-local `use`).
+ - Prefer `to_owned` for `&str` → `String`.
+ - Always use `foo.rs` instead of `foo/mod.rs` for module roots.
+ - Run styling and linting commands after every edit.
+