# Simplification report: Cargo.toml
**Verified against:** default features (S1–S4 checked under `--features full` for S1, default for S2–S4), toolchain `nightly` (from `rust-toolchain.toml`)
**Baseline:** 1 warning group → with all accepted changes: unchanged (0 regressions)
**Working tree:** restored, unchanged
## Summary
A mature library Cargo.toml with a well-structured feature graph. Two issues stand out: `full` and `full_no_plotting` maintain identical 19-item member lists in parallel, creating a drift risk; and three places list features that are already transitively implied. One dead optional dependency (`num-format`) has no source references and no feature entry.
---
## Suggestions
### S1 — Express `full` in terms of `full_no_plotting` · feature-dedup · safe · ✅ verified
**Location:** `Cargo.toml:106–128`
**Why:** `full` is `full_no_plotting` plus `plotting` and `parallel`. Keeping two separate 19-item lists is a drift trap — a feature added to one must be manually mirrored in the other. One line eliminates the duplication and makes the relationship explicit.
```toml
# before
full = [
"statistics",
"editing",
"transforms",
"channels",
"resampling",
"fixed-size-audio",
"beat-tracking",
"onset-detection",
"decomposition",
"dynamic-range",
"parametric-eq",
"peak-picking",
"pitch-analysis",
"processing",
"vad",
"iir-filtering",
"plotting",
"envelopes",
"random-generation",
"psychoacoustic",
"parallel",
]
```
```toml
# after
full = ["full_no_plotting", "plotting"]
```
---
### S2 — Remove redundant `random-generation` from `envelopes` · transitive-feature · safe · ✅ verified
**Location:** `Cargo.toml:97–102`
**Why:** `editing = ["statistics", "random-generation"]`. Since `envelopes` already lists `editing`, the `random-generation` entry is redundant — Cargo will activate it via `editing` regardless.
```toml
# before
envelopes = [
"dynamic-range",
"editing",
"random-generation",
"dep:rustfft"
]
```
```toml
# after
envelopes = [
"dynamic-range",
"editing",
"dep:rustfft"
]
```
---
### S3 — Remove redundant `statistics` from `plotting` · transitive-feature · safe · ✅ verified
**Location:** `Cargo.toml:96`
**Why:** `editing = ["statistics", "random-generation"]`. Since `plotting` already lists `editing`, listing `statistics` explicitly is redundant.
```toml
# before
plotting = ["dep:plotly", "dep:base64", "dep:serde_json", "channels", "transforms", "statistics", "editing"]
```
```toml
# after
plotting = ["dep:plotly", "dep:base64", "dep:serde_json", "channels", "transforms", "editing"]
```
---
### S4 — Remove dead `num-format` optional dependency · dead-dep · safe · ✅ verified
**Location:** `Cargo.toml:38`
**Why:** `num-format` is `optional = true`, is not activated by any `[features]` entry, and has no `use num_format::` or `num-format` references anywhere in `src/`, `examples/`, `benches/`, or `tests/`. Confirmed by grep. Removing it eliminates a crates.io download and a stale entry. Verified by deletion + `cargo check --features full` — no compile errors.
```toml
# before
num-format = { version = "0.4.4", optional = true }
```
```toml
# after
# (line removed)
```
---
## Flagged — review before publishing
### F1 — `[patch.crates-io]` self-patch · 🚩 flag
**Location:** `Cargo.toml:215–216`
```toml
[patch.crates-io]
audio_samples = { path = "." }
```
This patches the crate to itself. It's a common local-dev pattern that ensures internal doctests or examples that `use audio_samples` resolve to the workspace version rather than crates.io. However, it affects the resolver for anyone who depends on this crate and it reads oddly in a published Cargo.toml. The `cargo-toml.md` reference calls for an explicit ask before removing it. **Recommend confirming this is intentional** before shipping — if it's only needed for local dev, consider moving it to a workspace-level `Cargo.toml` or a local `.cargo/config.toml` patch instead.
---
## Not changed (considered, rejected)
- **`audioadapter` vs `dep:audioadapter` in `resampling`** — The `resampling` feature uses `"audioadapter"` and `"audioadapter-buffers"` without `dep:` prefix, relying on the implicit feature aliases. Switching to `dep:audioadapter` would suppress those implicit aliases (removing `audioadapter` as a public feature name). Since this changes the crate's visible feature surface, it is treated as a soft breaking-API concern and skipped.
- **Redundant items in `full_no_plotting`** — Many of its 19 entries are transitively implied by others in the list (e.g., `onset-detection` implies `transforms`, `peak-picking`, `processing`; `editing` implies `statistics`, `random-generation`). The list could shrink significantly. However, explicit membership in an aggregate feature is often intentional for documentation purposes, and once S1 is applied, fixing `full_no_plotting` also fixes `full`. Left for a follow-up pass if desired.
- **`[lib]` section** — `name = "audio_samples"` and `crate-type = ["rlib"]` are both Cargo defaults for a library package with a matching name. They could be dropped entirely, but this is purely cosmetic and not worth the noise.
- **`fixed-size-audio = []`** — Empty feature, same pattern as `bare-bones`, `vad`, `statistics`, etc. Intentional feature gates; do not remove.
