How to Hire a Rust Developer in 2026: Ownership, Safety, and What to Actually Test

The Rust hiring market has a gap problem. There are developers who have written Rust, and there are developers who understand Rust. The first group is large and growing. The second group is what you need for production code, and the gap between them is wider in Rust than in almost any other language.

The reason is the ownership model. Most languages let you ignore memory management until it breaks. Rust forces you to confront it upfront. Developers who push through that discomfort and internalize why Rust works the way it does can write code that is genuinely faster, safer, and more correct than equivalent Go or C++ code. Developers who find workarounds (clone everything, wrap everything in Arc<Mutex<>>, reach for unsafe) end up with code that compiles but carries none of the guarantees Rust promises.

Here is how to tell which kind you are hiring.

Where Rust is actually used in 2026

Before the screen, it helps to know why companies reach for Rust. The pattern is consistent across the largest deployments:

AWS uses Rust for Firecracker (the microVM hypervisor powering Lambda and Fargate) because they need bare-metal performance and zero GC pauses. Cloudflare uses it for edge workers for the same reason: short cold starts and predictable latency at scale. Discord switched parts of their message read state from Go to Rust to eliminate GC-related latency spikes. 1Password’s core vault logic is Rust, running on iOS, Android, and Windows from a single codebase through WASM.

The theme: latency sensitivity, memory efficiency, or safety-critical code. Rust is rarely the right choice for a CRUD API where Python or Go would ship in half the time. Knowing this shapes what you screen for, because a developer who has real Rust experience should have a clear answer to “when would you not use Rust.”

The ownership screen

The fastest technical signal is a conversation about ownership and borrowing. Give the candidate a short snippet:

fn first_word(s: String) -> &str {
    let bytes = s.as_bytes();
    for (i, &item) in bytes.iter().enumerate() {
        if item == b' ' {
            return &s[0..i];
        }
    }
    &s[..]
}

Ask them what is wrong with this code. A developer who understands Rust will immediately flag the lifetime issue: s is moved into the function (owned), but the function is trying to return a reference to data inside s. When the function ends and s is dropped, the reference would dangle. The fix is to take &str as the parameter instead, borrowing the string slice rather than owning the string.

The fix is not complicated. The diagnostic is: can they explain why the compiler refuses to accept it? If they reach for “add a lifetime parameter” without explaining what problem it solves, they have memorized the syntax without understanding the model.

Error handling

Ask how they handle errors that can come from multiple different types. This is a real-world Rust problem that most developers encounter within the first week of writing a real program.

A developer who knows Rust will talk about a few approaches:

The quick path is Box<dyn Error>, which erases the error type but gives you something that works:

fn read_config(path: &str) -> Result<Config, Box<dyn Error>> {
    let text = std::fs::read_to_string(path)?;
    let config: Config = serde_json::from_str(&text)?;
    Ok(config)
}

The more precise path is using a library like thiserror to define a custom error enum that implements std::error::Error:

#[derive(Debug, thiserror::Error)]
enum ConfigError {
    #[error("could not read config file: {0}")]
    Io(#[from] std::io::Error),
    #[error("invalid config format: {0}")]
    Parse(#[from] serde_json::Error),
}

The anyhow crate sits between these: better ergonomics than Box<dyn Error>, easier context attachment (.context("reading config file")), and still type-erased. Most production Rust applications use thiserror for library code (so callers can match on error variants) and anyhow for application code (where the human-readable message is what matters).

A developer who just returns unwrap() everywhere or who cannot articulate this tradeoff is writing code that will panic in production.

Async Rust is a separate skill

Threading and async have very different models in Rust. Ask about both:

For async, ask what tokio::spawn returns and why you might need to .await on the handle. Strong candidates will explain JoinHandle<T> and that .await propagates the panic if the task panicked.

For threading, ask what Send and Sync mean. These are marker traits, and understanding them is fundamental to writing correct concurrent code:

• Send means it is safe to transfer ownership of a value to another thread.
• Sync means it is safe to share a reference to a value across threads (T is Sync if &T is Send).

Rc<T> is neither Send nor Sync, which is why it cannot cross thread boundaries. Arc<T> is both, but only because the reference count uses atomic operations. A developer who does not know this cannot reason about why the compiler is refusing their code, which means they cannot fix it without help.

Questions worth asking

“Walk me through when you’d use unsafe. What would you try first to avoid it?”

Good answers mention FFI (calling into C libraries), low-level data structure internals (implementing a doubly-linked list), or performance-critical code that provably cannot be expressed safely. The “try first to avoid it” part is where you learn whether they treat unsafe as a last resort or as a convenience shortcut.

“What is the cost of calling clone() on a large Vec, and when is it worth it?”

This surfaces whether they think about performance at all. Cloning a Vec is O(n), copies every element, and allocates new heap memory. Worth it for correctness sometimes. Not worth it as a way to avoid dealing with the borrow checker.

“Describe a time when Rust’s type system caught a bug that would have shipped in another language.”

Real experience produces specific stories. “It caught a data race at compile time” or “the Send constraint caught a value I was about to share unsafely” are real answers. “It just makes code safer” is not an answer; it is the claim you want evidence for.

Red flags

A developer who reaches for clone() everywhere to avoid borrowing constraints is not actually working with Rust’s ownership model, they are working around it. This produces functional code but throws away most of the performance and safety benefits.

Developers who cannot explain what problem Arc<Mutex<T>> solves (shared mutable state across threads) should not be writing concurrent Rust. And developers who treat unwrap() as an error handling strategy are shipping programs that panic in production on edge cases.

Green flags

Strong Rust developers have opinions on the anyhow vs thiserror split. They know which crates they reach for and why. They can talk about a time the borrow checker forced them to restructure data in a way that turned out to be better. And they are honest about when Rust was the wrong tool.

If the role is backend services, check for sqlx or diesel experience. If it is WASM or cross-platform, check for the wasm-bindgen and wasm-pack toolchain. DevOps and infrastructure Rust often touches clap for CLIs and reqwest for HTTP.

We cover how vetting depth maps to hiring model in how to hire a vetted software developer. If you are filling a Rust role and want help designing the technical screen, reach out and we can work through what matters for your specific use case.