Stop Re-installing Your Tools

When you publish a CLI tool on crates.io, you’ll often get a familiar question (at least I did):

“How do I update it?”

The standard answer is usually:

cargo uninstall <crate>
cargo install <crate>

It works, but it’s clunky. For tbdflow, a tool designed to keep developers in their flow, forcing a two-step uninstall/re-install felt like going against the whole point of the project.

So I decided to let tbdflow update itself.

The Goal: Self-updating

The ideal flow should be:

tbdflow update

The command should:

• Check if a newer version is available on the project’s GitHub Releases.
• If so, download the right pre-compiled binary for the current platform.
• Replace the existing executable.
• If not, simply let the user know they’re already up to date.

No extra steps, no hunting down version numbers, just update and carry on.

The Solution: self_update

The self_update crate takes care of all the heavy lifting:

• Checking the current version against the latest.
• Fetching release assets from GitHub.
• Safely swapping the binary in place.

It’s simple to set up and works across platforms.

Implementation

1. Automate Releases with GitHub Actions (The Prerequisite)

The self_update crate works by looking for pre-compiled binaries attached to a GitHub Release. To make this happen automatically, I created a workflow that triggers whenever I push a new version tag (e.g., v0.10.2).

This workflow does two key things:

• It uses a “matrix build” to compile tbdflow for multiple platforms (Linux, macOS and Windows).

• It then creates a new GitHub Release and uploads all the compiled binaries as assets.

Whenever I tag a new version, a release with all the necessary files will be published on GitHub (and crates.io but that’s another flow)

2. Add the dependency

In Cargo.toml:

self_update = "0.42.0"

3. Add the CLI command

In cli.rs:

#[derive(clap::Subcommand, Debug)]
pub enum Commands {
    // ...
    /// Checks for a new version of tbdflow and updates it if available.
    Update,
}

4. Wire up the logic

In main.rs:

Commands::Update => {
    println!("{}", "--- Checking for updates ---".blue());
    let status = self_update::backends::github::Update::configure()
        .repo_owner("cladam")
        .repo_name("tbdflow")
        .bin_name("tbdflow")
        .show_download_progress(true)
        .current_version(self_update::cargo_crate_version!())
        .build()?
        .update()?;
    
    println!("Update status: `{}`!", status.version());
    if status.updated() {
        println!("{}", "Successfully updated tbdflow!".green());
    } else {
        println!("{}", "tbdflow is already up to date.".green());
    }
}

This is now available from tbdflow-0.10.2 onwards.

Wrapping Up

It’s a small addition, but it makes a big difference. tbdflow update now gives users the latest version in one step, no uninstalling, no reinstalling. It fits the tool’s philosophy: keep things simple, reduce friction, and let people focus on their work.

If you’re building a CLI in Rust, adding a self-update command is worth considering. Your users will appreciate it.