Two kinds of feature flag
go-tool-base has feature flags: switches that decide which built-in commands are live in a given run. rust-tool-base has those too. But it also has a second, completely separate kind of flag, and the difference between …
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forbid means forbid, until linkme needs a word
There’s a line at the top of every production crate in rust-tool-base that I’m quietly proud of: #![forbid(unsafe_code)]. And there are a couple of files that have to say #![allow(unsafe_code)] instead. Not because I …
A framework that contains no unsafe
“It’s written in Rust” gets thrown around as if it were a memory-safety guarantee. It mostly isn’t. Rust is memory-safe by default, which is a wonderful thing, but the unsafe keyword exists precisely so any crate, any …
Reloading config without a restart
A config file changes. Someone edits a setting, rotates a credential, flips a feature flag. How does the running process find out? For most processes the answer is blunt: it doesn’t, until you restart it. For a …
A signing key needs somewhere to live
I left a door open a couple of posts ago, and it’s been quietly bothering me ever since. When I wrote about verifying your own downloads, I was honest that a checksum sitting next to the binary only catches accidents. …
Waivers with an expiry date
A vulnerability scanner gives you a yes or a no. Is there a known advisory on a path you actually use? Yes, or no. That’s genuinely useful, and you should run one. But it’s a snapshot, taken on the day you ask, and …
A builder that won't compile if you forget a field
go-tool-base configures things with functional options, and if you forget a required one, the best case is a runtime failure and the worst case is an empty value sailing silently into everything downstream. Most builder …
Process isolation won't save you from the filesystem
A test that passed every single time I ran it on its own, and failed maybe one run in five when I ran the whole suite. The failure was always the same: the self-update test downloaded a release archive, went to extract …
Registering commands without life before main
I ended the last post promising to show how a Rust command registers itself when the language flatly refuses to run any of your code before main(). This is that post, and it’s a lovely example of reaching the same …
Verifying your own downloads: how I solved it for self-updating CLI tools
Way back in the introduction I promised I’d come back to the self-update integrity checks. Here we are. And the starting point is a slightly uncomfortable admission: for a good long while, go-tool-base’s update command …
