By the numbers

Data collected on 2026-04-30 against commit 2250bb0. Counts come from git, wc -l, and Cargo.toml.

Size

The codebase is small and overwhelmingly Rust.

xychart-beta horizontal
    title "Lines of code by area"
    x-axis ["src/walk.rs", "src/cli.rs", "src/main.rs", "src/exec/", "src/fmt/", "src/filter/", "tests/tests.rs"]
    y-axis "Lines" 0 --> 3000
    bar [738, 953, 536, 652, 368, 561, 2803]

Area	Files	Lines
src/ (Rust source, excluding tests)	21 .rs files	~4,780
tests/tests.rs (integration tests)	1	2,803
tests/testenv/mod.rs (test harness)	1	344
Cargo.toml	1	~100
Makefile	1	56
doc/fd.1 (groff man page)	1	~600
CHANGELOG.md	1	861
README.md	1	~700

The biggest single file is tests/tests.rs at 2,803 lines. The biggest production module is src/cli.rs at 953 lines (the entire clap definition lives there). After that the largest source files are src/walk.rs (738) and src/exec/mod.rs (473).

Activity

Metric	Value
Total commits	1,894
First commit	2145973 — Initial commit, 2017-05-09
Latest commit (at snapshot)	2250bb0 — Merge pull request #1980 …, 2026-04-24
Commits in the last 12 months	~480
Unique authors (all time)	230
Unique authors in the last 12 months	31
Tags / releases shipped	60+ (see git tag)
Latest release	10.4.2 (declared in Cargo.toml)

Bot-attributed commits

git log --all --pretty=format:"%H %s%n%b" \
  | grep -ciE "co-authored-by:.*(bot|dependabot|github-actions|copilot|factory-droid)"

Returns 8 commits with bot or AI co-authorship trailers. Of those:

• 7 carry Co-authored-by: dependabot[bot]
• 1 carries Co-authored-by: Copilot <…@users.noreply.github.com>
• 2 unrelated lines mention Anthropic Claude in commit bodies (older PR descriptions)

Among first-author commits, dependabot[bot] accounts for 230 of 1,894 commits (≈12%) — the only bot in fd's commit history. This is a lower bound for AI-assisted work because IDE-integrated assistants leave no git trace.

Churn hotspots (last 90 days)

The most touched files in the most recent 90-day window are:

File	Recent commits	What changed
src/cli.rs	many	Several flag/UX fixes (path-separator pattern detection, --ignore-parent, ...)
src/main.rs	many	Argument validation, --full-path handling
tests/tests.rs	many	Tests added alongside almost every behavioural change
CHANGELOG.md	regular	Updated by every contributor (per CONTRIBUTING.md)
.github/workflows/CICD.yml	several	Action version bumps via dependabot
Cargo.lock / Cargo.toml	regular	Dependency bumps

Complexity snapshot

Module / dir	Files	Lines	Notes
src/cli.rs	1	953	Single file with clap derive + custom Exec parser. Heaviest doc-comment density in the project (long --help strings).
src/walk.rs	1	738	Hot path: parallel walker, batching, receiver buffer. Has its own unit tests.
src/main.rs	1	536	run, construct_config, extract_command, determine_ls_command, the DEFAULT_LS_COLORS constant.
src/exec/	3	652	mod.rs (473) + command.rs (115) + job.rs (64).
src/fmt/	2	368	mod.rs (281) + input.rs (87). Used by both --exec and --format.
src/filter/	4	572	size.rs (219) + time.rs (202) + owner.rs (140) + mod.rs (11).
src/dir_entry.rs	1	155	Lazily computes metadata and color style.
src/output.rs	1	175	Path printing with colors, hyperlinks, custom separators.
src/regex_helper.rs	1	105	Smart-case + leading-dot detection.
src/hyperlink.rs	1	87	OSC 8 URL builder.
src/filesystem.rs	1	156	Cross-platform path helpers.
src/error.rs	1	3	A single print_error function.

The test-to-code ratio is unusually high: ~2,800 lines of integration tests for ~4,800 lines of production code, plus per-module #[cfg(test)] mod tests blocks in every filter and helper module.

Dependency counts

From Cargo.toml:

Kind	Count
Direct runtime dependencies	18 (e.g. clap, regex, ignore, globset, crossbeam-channel, lscolors, nu-ansi-term, argmax, jiff, etcetera, normpath, aho-corasick, anyhow, ctrlc, faccess)
Optional features	2 (use-jemalloc, completions)
Unix-only deps	2 (nix, libc)
Selectively-targeted deps	1 (tikv-jemallocator, gated by a long target-cfg list)
Dev dependencies	4 (diff, tempfile, filetime, test-case)

Test coverage signal

Indicator	Value
Integration tests (tests/tests.rs)	2,803 lines
Inline unit-test modules	At least 6 (in walk.rs, regex_helper.rs, filesystem.rs, exit_codes.rs, exec/mod.rs, fmt/mod.rs, fmt/input.rs, filter/size.rs, filter/time.rs, filter/owner.rs, hyperlink.rs)
Custom test harness	tests/testenv/mod.rs (344 lines) builds the binary once and provides TestEnv::assert_output
CI matrix	Multiple targets per .github/workflows/CICD.yml, plus a separate MSRV job

For a closer look at how tests are organised see how-to-contribute/testing.