This content originally appeared on DEV Community and was authored by 阿豪
TL;DR: Used bloaty-metafile to analyze binary size, disabled default features on key dependencies, reduced size by 59% (11MB → 4.5MB)
The Problem
I’ve been working on easy-install (ei), a CLI tool that automatically downloads and installs binaries from GitHub releases based on your OS and architecture. Think of it like a universal package manager for GitHub releases.
Example: ei ilai-deutel/kibi automatically downloads the right binary for your platform, extracts it to ~/.ei, and adds it to your shell’s PATH.
I wanted to run this on OpenWrt routers, which typically have only ~30MB of available storage. Even with standard release optimizations, the binary was still ~10MB:
[profile.release]
debug = false
lto = true
strip = true
opt-level = 3
codegen-units = 1
panic = "abort"
Not good enough.
The Analysis
I used bloaty-metafile to analyze where the bloat was coming from. Turns out, ~80% of the binary size came from just 20% of dependencies:
- clap – CLI argument parsing
- reqwest – HTTP downloads
- tokio – Async runtime
-
regex – Parsing non-standard release filenames (e.g.,
biome-linux-x64-musl→x86_64-unknown-linux-musl) - easy-archive – Archive extraction (tar.gz, zip, etc.)
The Optimization
The key insight: disable default features and only enable what you actually use.
1. clap – Saved 100-200KB
clap = { version = "4", features = ["derive", "std"], default-features = false }
Only enable basic functionality. No color output, no suggestions, no fancy formatting.
2. reqwest – Saved ~4MB (!!)
reqwest = { version = "0.12", features = [
"json",
"rustls-tls", # Instead of native-tls
"gzip"
], default-features = false }
Switching from native-tls to rustls-tls was the biggest win. Native TLS pulls in system dependencies that bloat the binary significantly.
3. tokio – Saved ~100KB
tokio = { version = "1", features = [
"macros",
"rt-multi-thread",
], default-features = false }
Only enable the multi-threaded runtime and macros. No I/O, no time, no sync primitives we don’t use.
4. regex – Saved ~1MB
regex = { version = "1", default-features = false, features = ["std"] }
Since we only use regex occasionally for URL parsing, we can disable Unicode support and other features.
5. easy-archive – Saved ~1MB
Only enable tar.gz decoding, skip encoding and other formats we don’t need.
Results
Before: 11MB
After: 4.5MB
Most crates enable way more than you need. The 80/20 rule applies here – optimizing a few key dependencies can yield massive savings.
Links:
This content originally appeared on DEV Community and was authored by 阿豪