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microvms-agentd

Dead code

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The compiler already owns most of this question. rustc’s unused_imports and dead_code are warn-by-default, Rust 1.97 added dead_code_pub_in_binary, and cargo clippy --all-targets --all-features over all seven workspace members exits 0 with zero warnings — verified on a forced fresh re-check, not a warm cache, with every .rs file in agentd, microvms-cli, microvms-core, microvms-js, microvms-py, model, and protocol touched first. Nothing crate-private is dead, and no import is unused anywhere rustc can see. Restating that would add nothing.

What the compiler cannot decide is what this file covers:

  • A pub item in microvms-core with zero in-repo callers may still be live API. The crate has three consumers (microvms-cli, microvms-py, microvms-js), and protocol is consumed by agentd and microvms-core.
  • Items reached only through #[pyclass] / #[pymethods] / #[pyfunction] / #[pymodule] or #[napi] are dispatched by CPython and Node, never by a Rust caller. They read as uncalled and are not dead. #[derive(Serialize, Deserialize)] impls, trait impls satisfying a bound, and #[test] functions read the same way.
  • napi-rs renames snake_case Rust to camelCase JS, so a #[napi] export exercised only from microvms-js/__test__/*.mjs is invisible to a snake_case search.

Method: a symbol is a candidate when no edge of kind calls | references | instantiates | imports | implements | extends targets it in the CodeGraph index (.codegraph/codegraph.db, 4,430 nodes / 16,638 edges), and no textual reference to it — or to its camelCase / #[napi(js_name)] / #[pyo3(name)] alias — exists anywhere in the git-tracked tree. contains edges are excluded because every symbol is contains-reachable from its own file node. The funnel: 1,398 zero-inbound Rust symbols → 551 after dropping test files and #[cfg(test)] modules → 465 after dropping two whole-file test-only modules → 112 after the alias-aware reference search → 2 after removing 110 trait and language-protocol members → 1 after hand-dropping a trait associated type (microvms-js/src/exec.rs:267, type Return = () inside impl AsyncGenerator for ExecStream) that the automated filter missed because it matched trait methods but not associated types. No dead-code analyzer is integrated in this repo (no cargo-udeps, cargo-machete, vulture, or knip in mise.toml, Cargo.toml, deny.toml, or .github/workflows/), so the index is the analyzer.

Unreferenced exports

Section titled “Unreferenced exports”
Symbol Path Last modified
SessionBuilder::with_timeout microvms-core/src/session/mod.rs:508 2026-08-15

Confidence: high. git grep -n "with_timeout\|withTimeout" -- . over the whole git-tracked tree returns exactly one line — the declaration. Every sibling on the same builder has a caller: with_minter (microvms-core/src/session/mod.rs:479) from microvms-cli/src/seam.rs, microvms-core/src/sandbox.rs, and microvms-core/tests/turmoil_client.rs; with_proxy_auth (microvms-core/src/session/mod.rs:487) from microvms-core/tests/turmoil_client.rs; with_backend (microvms-core/src/session/mod.rs:494) from microvms-cli/src/guards.rs and microvms-core/tests/turmoil_client.rs; with_port (microvms-core/src/session/mod.rs:501) from microvms-cli/src/seam.rs and microvms-core/src/sandbox.rs.

The field it writes is live — only the setter is unreached. SessionBuilder::build reads self.timeout at microvms-core/src/session/mod.rs:517 and :529, and Session::run back-fills a per-request None from it at microvms-core/src/session/mod.rs:119-120. Session::builder is the sole constructor (microvms-core/src/session/mod.rs:230-231) and seeds every path with DEFAULT_REQUEST_TIMEOUT (microvms-core/src/session/mod.rs:237).

What would falsify this. Three conditions hold; any one of them failing moves this row out of the table.

  1. No unseen downstream consumer. microvms-core is a library crate, so a pub method is reachable by anything that depends on it. The package is published on crates.io and has language bindings. This analysis cannot establish the absence of downstream callers, so removing public API requires a compatibility decision; lack of local references is insufficient.
  2. No binding re-exports it. microvms-py/microvms.pyi contains no with_timeout, and no withTimeout exists in microvms-js.
  3. No host runtime dispatches to it. Its only attribute is #[must_use] — no #[napi], no #[pymethods].

Related defect in the same construct. The builder’s doc comment at microvms-core/src/session/mod.rs:229 reads “A builder, for the cases that need a port, a timeout, or a custom backend.” The port case and the backend case each have callers; the timeout case has none. The comment asserts a motivating case that does not exist in the tree.

Unreferenced files

Section titled “Unreferenced files”

none

All 200 git-tracked files resolve to an inbound reference. Every non-root .rs file has a mod declaration or is cargo-auto-discovered by one of the patterns */src/lib.rs, */src/main.rs, */build.rs, */src/bin/*.rs, */tests/*.rs, */examples/*.rs. Four files that a basename search calls orphans, each cleared against its real invocation site:

File Reached by
microvms-py/tests/test_stubs.py pytest microvms-py/tests -q at .github/workflows/ci.yml:308; pytest auto-discovers test_*.py, so no file names it
microvms-js/__test__/support/decimal.mjs microvms-js/__test__/cost.mjs:40
microvms-js/__test__/support/sse.mjs microvms-js/__test__/cost.mjs:41, microvms-js/__test__/errors.mjs:40, microvms-js/__test__/exec.mjs:44, microvms-js/__test__/process.mjs:31, microvms-js/__test__/session.mjs:33
conformance/infra/main.tf terraform -chdir=conformance/infra at mise.toml:53, mise.toml:93, mise.toml:307, mise.toml:538

Two files are compiled only under cfg(test) and are live test code, not dead source: microvms-cli/src/guards.rs (inner #![cfg(test)] at microvms-cli/src/guards.rs:20, plus #[cfg(test)] mod guards; at microvms-cli/src/main.rs:36-37) and microvms-core/src/control/fake.rs (#[cfg(test)] pub(crate) mod fake; at microvms-core/src/control/mod.rs:928-929).

Dead imports

Section titled “Dead imports”
Path Symbol Imported from
microvms-cli/src/commands/lifecycle.rs:1168 _DocsOnly (alias of ControlPlane) microvms_core::control::ControlPlane, re-bound from microvms-cli/src/commands/lifecycle.rs:70
microvms-cli/src/commands/attached.rs:932 _DocsOnly (alias of ErrorKind) microvms_core::ErrorKind, re-bound from microvms-cli/src/commands/attached.rs:40

Confidence: high that nothing names _DocsOnly; do not delete either line on its own. Both carry #[allow(unused_imports, reason = …)], so rustc never reports them, and both are the only allow attributes of this family in the workspace. Neither is independently removable. Measured by copying the git-tracked tree to a scratch directory, deleting each three-line construct (doc comment, attribute, use), and rebuilding:

The two differ in whether the whole construct earns its place:

  • ControlPlane is a trait, so its name never appears in an expression; the :70 import is what makes [ControlPlane] at microvms-cli/src/commands/lifecycle.rs:10 resolve. Removing the pair means removing that doc link. Load-bearing as a unit.
  • ErrorKind is named nowhere in microvms-cli/src/commands/attached.rs except its import at :40 and the two _DocsOnly lines at :930-932. The only documentation that links [ErrorKind] is the doc comment justifying the import that makes it resolvable. Removable as a unit — :40’s ErrorKind, plus all three lines at :930-932.

Non-Rust surfaces, both clean. uvx ruff check --select F401,F811,F841 over all 17 tracked .py files plus microvms-py/microvms.pyi reports no findings; F401 is in the repo’s own selected set (ruff.toml) and mise.toml:91 runs ruff check . across the whole repo. The eight microvms-js/__test__/*.mjs files have no linter, so their import … from '…' bindings were checked directly for non-comment uses: zero unused.

See also

Section titled “See also”