dwdiff

the free dwdiff Unicode-aware word-level diff with full CJK support, distributed as a single self-contained static binary.

dwdiff is vendored from dwdiff 2.1.4 (G.P. Halkes, GPL-3.0) with libicu 78.3 bundled and statically linked — no system ICU needed.

What it is

dwdiff is a word-level diff tool like wdiff, but Unicode-aware. The key difference shows up on CJK text:

$ dwdiff -d '，' cn-a.txt cn-b.txt
体育老师无奈，[-总被佔课现象困扰-]{+总被占课现象困扰+}。

With the bundled ICU 78.3, dwdiff segments CJK phrases correctly and surfaces intra-line character changes. Stock wdiff would treat the whole CJK line as one giant "word" and show it as a single delete+add.

Install (one line)

The fastest path uses x-cmd:

x eget ljh-sh/dwdiff

This installs dwdiff and the man page to ~/.local/bin/. See install for the manual walkthrough.

Platform matrix

Every release builds 5 targets via GitHub Actions on native runners. Linux uses musl-static (Alpine toolchain) so the binary runs on Alpine, Debian/Ubuntu, RHEL/Fedora, Arch — every Linux distro — with zero system-library dependencies. There is intentionally no separate glibc/dynamic Linux variant.

target	runner	linkage	archive
`x86_64-linux-musl`	`ubuntu-latest` + Alpine 3.20 docker	fully static musl (incl. ICU)	`.tar.gz`
`aarch64-linux-musl`	`ubuntu-24.04-arm` + Alpine 3.20 docker	fully static musl (incl. ICU)	`.tar.gz`
`aarch64-macos`	`macos-14`	static, system libc/libSystem	`.tar.gz`
`x86_64-macos`	`macos-14` (cross from aarch64)	static, system libc/libSystem	`.tar.gz`
`x86_64-windows`	`windows-latest` + MSYS2 + mingw64	fully static (no DLLs)	`.zip`

aarch64-windows and additional targets are deferred.

Security

See security for the source-level audit. The audit covers both vendored upstreams — dwdiff 2.1.4 and ICU 78.3 — and includes a CJK acceptance test that gates every release: the build script's CJK round-trip fixture proves ICU is actually linked in (without ICU, dwdiff's CJK output is just [-整行-]{+整行+} with no intra-line visibility).