zerobrew

Install

curl -fsSL https://zerobrew.rs/install | bash

The installer updates your shell config. After it finishes, restart your terminal or run the source command it prints.

Or via Homebrew:

brew install zerobrewhq/tap/zerobrew

Update zerobrew

If you used the standalone installer, rerun it:

curl -fsSL https://zerobrew.rs/install | bash
zb --version

If you installed with Homebrew:

brew update && brew upgrade zerobrew

If you installed from the old lucasgelfond/zerobrew tap, it’s no longer updated. Switch to the new one:

brew uninstall zerobrew
brew untap lucasgelfond/zerobrew
brew install zerobrewhq/tap/zerobrew

The cachebag/zerobrew and zerobrewhq/zerobrew taps were moved to zerobrewhq/tap and keep updating; nothing to do.

Quick start

To opt in to a brew compatibility entrypoint:

zb install-alias brew
brew install jq
zb install-alias brew --remove

This creates brew -> zb-brew beside zb; ensure that directory is on PATH. You can also enable it during installation:

curl -fsSL https://zerobrew.rs/install | bash -s -- --brew-compat

Enabling it refuses existing Homebrew or other brew entrypoints on PATH and standard Homebrew locations, and never replaces an existing file. Removing it only deletes zerobrew’s own symlink. If zb-brew is missing, reinstall zerobrew.

The entrypoint supports install, uninstall, list, info, outdated, upgrade, doctor, bundle, and update, using the arguments and output supported by zb. cleanup runs zb gc and only removes unreferenced store entries. update refreshes the formula index; it does not update zerobrew itself. Commands such as search, services, and tap, and flags such as --cask and list --formula, are not implemented and fail with a compatibility error. zb migrate requires real Homebrew on PATH and refuses this entrypoint.

zb install jq                   # install one package
zb install wget git             # install multiple
zb bundle                       # install from Brewfile
zb bundle install -f myfile     # install from custom file
zb bundle dump                  # export installed packages to Brewfile
zb bundle dump -f out --force   # dump to custom file (overwrite)
zb uninstall jq                 # uninstall one package
zb outdated                     # list packages with newer versions
zb upgrade                      # upgrade all outdated packages
zb upgrade jq wget              # upgrade specific packages
zb reset                        # uninstall everything
zb gc                           # garbage collect unused store entries
zbx jq --version                # run without linking

Automatic initialization (--auto-init or ZEROBREW_AUTO_INIT=true) and zb reset create data directories without changing shell configuration. Run zb init explicitly to configure your shell, or zb init --no-modify-path to leave it unchanged.

Performance snapshot

Measured on 2026-10-23 with zerobrew 0.4.2 and Homebrew 7.0.10 on macOS 26.6.2, MacBook Pro (M3 Pro, 18 GB RAM), wired, ~436 Mbit/s download bandwidth. Homebrew started with nothing installed.

• Cold: the package and all of its dependencies uninstalled, empty download cache.
• Warm: the package and all of its dependencies uninstalled, downloads from the cold run still cached.
• The median package was 7.5x faster cold and 62x faster warm. Per package, cold ranged from 1.7x (go) to 27x (certifi) and warm from 4.0x (fontconfig) to 275x (p11-kit). 86 of the 100 packages installed at least 5x faster cold, and 19 installed 100x faster or more warm.
• Both tools run post-install steps. ca-certificates’ step builds the CA bundle from the system keychain, which costs Homebrew about 8 seconds and used to cost zerobrew the same on every package that depends on it, most of the table. Since 0.4.2 zerobrew builds that bundle in process, byte for byte, in well under a second; the run from before that (results/2026-10-12) was 3.6x cold. fontconfig’s fc-cache is the same kind of step and is not ported yet (#448), which is what holds fontconfig, harfbuzz, cairo and pango under 10x warm.
• Cold installs are bound by the link. The same run on a ~80 Mbit/s connection two days earlier (results/2026-10-21) came out at 3.7x cold overall, with go and llvm at the speed of the download, while the median package was still 6.2x. Homebrew’s total barely moves with bandwidth; zerobrew’s is mostly bandwidth.
• Warm installs use more disk. After an uninstall brew keeps the bottle, we keep the bottle and the unpacked keg in the store. That is the main tradeoff here.

Full results

Package	Homebrew (cold)	ZB (cold)	Cold speedup	Homebrew (warm)	ZB (warm)	Warm speedup
Overall (100 packages)	852.82s	108.73s	7.84x	755.53s	29.91s	25.26x
ca-certificates	8.35s	361ms	23.13x	7.69s	29ms	265.28x
openssl@3	11.44s	1.15s	9.92x	10.58s	63ms	167.95x
xz	2.43s	391ms	6.22x	1.62s	28ms	57.93x
sqlite	3.10s	450ms	6.90x	2.31s	27ms	85.44x
readline	2.40s	524ms	4.57x	1.62s	26ms	62.23x
icu4c@78	3.00s	871ms	3.44x	1.94s	27ms	71.96x
[email protected]	17.85s	1.86s	9.61x	17.10s	624ms	27.40x
awscli	31.02s	3.05s	10.17x	29.72s	884ms	33.62x
node	32.46s	2.08s	15.58x	31.18s	889ms	35.07x
harfbuzz	25.17s	4.16s	6.05x	23.51s	2.80s	8.40x
ncurses	3.04s	779ms	3.90x	2.28s	48ms	47.54x
gh	2.33s	584ms	3.98x	1.47s	36ms	40.83x
pcre2	2.54s	484ms	5.25x	1.75s	33ms	52.91x
libpng	2.46s	348ms	7.06x	1.69s	27ms	62.41x
zstd	3.93s	431ms	9.13x	3.14s	34ms	92.32x
glib	6.91s	924ms	7.48x	5.89s	98ms	60.09x
lz4	2.41s	311ms	7.75x	1.68s	26ms	64.65x
gettext	4.53s	951ms	4.76x	3.66s	65ms	56.25x
libngtcp2	12.29s	1.50s	8.22x	11.43s	516ms	22.15x
libnghttp3	2.42s	351ms	6.89x	1.67s	26ms	64.04x
pkgconf	2.47s	311ms	7.95x	1.68s	27ms	62.07x
libunistring	2.45s	421ms	5.81x	1.69s	27ms	62.63x
mpdecimal	2.46s	314ms	7.84x	1.67s	26ms	64.27x
brotli	2.48s	375ms	6.61x	1.69s	27ms	62.41x
jpeg-turbo	2.51s	420ms	5.97x	1.71s	28ms	60.96x
xorgproto	2.14s	360ms	5.95x	1.36s	29ms	46.79x
ffmpeg	22.61s	1.73s	13.04x	21.20s	592ms	35.81x
cmake	3.19s	1.02s	3.12x	1.89s	80ms	23.56x
libnghttp2	2.46s	313ms	7.87x	1.67s	26ms	64.04x
go	4.79s	2.77s	1.73x	3.50s	169ms	20.74x
uv	2.37s	606ms	3.91x	1.44s	26ms	55.23x
gmp	2.46s	446ms	5.51x	1.69s	27ms	62.44x
libtiff	8.00s	541ms	14.78x	7.17s	54ms	132.81x
fontconfig	10.75s	3.60s	2.98x	9.79s	2.47s	3.96x
[email protected]	15.95s	1.60s	9.97x	15.26s	189ms	80.74x
git	6.93s	1.17s	5.92x	5.52s	103ms	53.56x
little-cms2	8.76s	546ms	16.05x	8.00s	56ms	142.79x
dav1d	2.48s	330ms	7.52x	1.71s	26ms	65.62x
openexr	11.36s	638ms	17.80x	10.40s	66ms	157.59x
c-ares	2.50s	330ms	7.56x	1.73s	33ms	52.42x
tesseract	39.87s	4.37s	9.13x	38.24s	2.86s	13.38x
p11-kit	10.11s	446ms	22.68x	9.34s	34ms	274.65x
imagemagick	17.23s	3.10s	5.57x	16.23s	84ms	193.27x
zlib	2.42s	307ms	7.87x	1.66s	26ms	63.69x
libx11	6.10s	828ms	7.37x	5.32s	184ms	28.91x
freetype	3.94s	438ms	9.00x	3.20s	32ms	100.03x
protobuf	4.06s	576ms	7.06x	3.30s	62ms	53.19x
gnupg	25.70s	1.07s	23.95x	24.34s	189ms	128.76x
openjph	8.81s	554ms	15.90x	8.00s	56ms	142.82x
libtasn1	2.45s	338ms	7.25x	1.71s	28ms	61.00x
ruby	18.05s	3.84s	4.70x	17.75s	1.34s	13.28x
gnutls	18.21s	978ms	18.62x	16.46s	139ms	118.40x
expat	2.48s	310ms	8.01x	1.67s	27ms	61.93x
libsodium	2.49s	337ms	7.39x	1.71s	27ms	63.44x
simdjson	2.49s	405ms	6.15x	1.69s	26ms	65.08x
gemini-cli	33.61s	2.25s	14.91x	32.56s	917ms	35.50x
libarchive	5.44s	464ms	11.73x	4.74s	37ms	128.08x
pyenv	15.43s	1.69s	9.16x	14.56s	544ms	26.76x
pixman	2.64s	345ms	7.64x	1.71s	27ms	63.33x
curl	19.71s	1.61s	12.20x	18.61s	570ms	32.65x
opus	2.43s	345ms	7.05x	1.69s	26ms	65.12x
unbound	14.67s	1.54s	9.51x	13.73s	554ms	24.79x
cairo	22.24s	4.03s	5.52x	20.97s	2.77s	7.56x
pango	28.60s	4.10s	6.97x	27.39s	2.79s	9.80x
leptonica	10.53s	624ms	16.88x	9.85s	65ms	151.58x
libxcb	5.18s	755ms	6.86x	4.39s	139ms	31.55x
jpeg-xl	15.14s	720ms	21.03x	14.04s	72ms	194.96x
coreutils	13.36s	1.60s	8.37x	12.38s	529ms	23.41x
certifi	9.07s	342ms	26.54x	8.34s	37ms	225.51x
krb5	12.54s	1.50s	8.33x	11.66s	510ms	22.86x
docker	2.25s	533ms	4.21x	1.39s	27ms	51.48x
libheif	12.14s	736ms	16.49x	11.27s	66ms	170.77x
webp	4.68s	432ms	10.84x	3.95s	35ms	112.74x
libxext	6.97s	804ms	8.67x	6.20s	189ms	32.80x
libxau	2.86s	346ms	8.26x	2.15s	32ms	67.31x
gcc	11.91s	2.48s	4.80x	9.94s	72ms	138.01x
bzip2	2.10s	300ms	7.01x	1.31s	26ms	50.54x
libxdmcp	2.89s	349ms	8.28x	2.14s	34ms	63.03x
abseil	3.02s	545ms	5.54x	2.18s	54ms	40.37x
xcbeautify	2.13s	371ms	5.74x	1.35s	27ms	49.93x
libuv	2.50s	340ms	7.34x	1.71s	27ms	63.30x
giflib	2.43s	293ms	8.31x	1.69s	27ms	62.67x
utf8proc	2.46s	313ms	7.88x	1.68s	26ms	64.62x
libxrender	6.94s	798ms	8.69x	6.14s	182ms	33.74x
m4	2.11s	292ms	7.21x	1.31s	26ms	50.42x
graphite2	2.42s	304ms	7.97x	1.68s	26ms	64.77x
openjdk	34.14s	6.09s	5.60x	31.67s	2.81s	11.26x
uvwasi	3.20s	328ms	9.75x	2.45s	29ms	84.52x
libffi	2.47s	329ms	7.50x	1.67s	26ms	64.31x
libdeflate	2.47s	330ms	7.47x	1.68s	26ms	64.73x
llvm	17.09s	6.09s	2.81x	10.51s	172ms	61.10x
aom	3.35s	529ms	6.33x	2.50s	32ms	78.19x
lzo	2.48s	289ms	8.57x	1.69s	27ms	62.74x
libevent	12.35s	1.47s	8.38x	11.50s	507ms	22.69x
libgpg-error	5.26s	861ms	6.11x	4.45s	71ms	62.68x
libidn2	5.28s	765ms	6.90x	4.41s	72ms	61.29x
berkeley-db@5	3.96s	1.44s	2.75x	2.84s	57ms	49.81x
deno	11.83s	1.08s	10.97x	10.80s	59ms	183.03x
libedit	2.46s	329ms	7.47x	1.68s	26ms	64.69x
oniguruma	2.49s	328ms	7.60x	1.68s	26ms	64.62x

To reproduce, run just bench --full results/ on a machine with nothing installed in Homebrew. It resets zerobrew, uninstalls everything it installed in Homebrew, and writes a table to results/benchmark.md.

A smaller version runs in CI: the parity workflow installs a fixed set of formulae with both tools on the same runner and compares the resulting prefixes byte for byte, and the timing workflow times those formulae plus node and [email protected], cold and warm, with both tools and with the last zerobrew release.

The nightly timing run fails if zerobrew is less than 1.5x faster than Homebrew cold or 3x warm on any of them, or more than 20% slower than the last release overall.

A note on how we are achieving these speeds

WRT Homebrew, I want it to be clear that both brew and zerobrew install the same bottles from Homebrew’s build farm.

The difference is what happens after the download: Homebrew runs Ruby to evaluate the formula, unpacks, rewrites paths with install_name_tool, and re-signs each binary one at a time, while zerobrew does the relocation in-process and links from a content-addressed store, so it pays for the download once and almost nothing after.

I want it to be clear that we are basically nothing without Homebrew’s bottle build farm. Every package zerobrew installs is one they built, tested and published. We don’t compile anything, we don’t maintain formulae, and none of these numbers exist without that work. The speed comes from how the artifacts are installed, not from what’s in them.

This is a good read, if you’re interested in what zerobrew is and isn’t: Standing on the shoulders of Homebrew by Andrew Nesbitt. It makes the point better than I can.

nanobrew:

nanobrew’s published numbers time a “warm install” of a package that is already installed, which is an early exit, not an install, and compare against zerobrew 0.1.0.

Every number above is a real install from an uninstalled state, with the script and the full log in this repo, so you can run it yourself.

Relationship with Homebrew

zerobrew is more of a performance-optimized client for the Homebrew ecosystem. We rely on:

• Homebrew’s formula definitions (homebrew-core)
• Homebrew’s pre-built bottles when available
• Homebrew’s package metadata and infrastructure

Our innovations focus on:

• Content-addressable storage for deduplication
• APFS clonefiles for zero-overhead copying
• Source build fallback using Homebrew’s Ruby DSL

zerobrew is experimental. We recommend running it alongside Homebrew rather than as a replacement, and do not recommend purging homebrew and replacing it with zerobrew unless you are absolutely sure about the implications of doing so.

Project status

• Status: Experimental, but quite useful. I (@cachebag) daily drive it myself.
• Feedback: If you hit incompatibilities, please open an issue or PR.
• License: Dual-licensed under Apache 2.0 OR MIT, at your choice. The source build shim and the post-install runner are derived from Homebrew and are covered by its BSD 2-Clause license.