March 23, 2026
Orphan Rule, Big Family Feud
An Incoherent Rust
Fans feud over Rust’s “orphan rule” as safety purists clash with pragmatists
TLDR: A viral post says Rust’s safety rules make replacing popular libraries too hard, locking in early winners. The community split fast: defenders say the rules keep quality high, critics call it purity over practicality; wrappers help, but the brawl over safety vs. agility raged on.
The blog “An Incoherent Rust” lit a fuse under the Rust crowd by arguing that Rust’s strict rules make it hard to swap out core libraries—especially for tasks like saving and loading data. Translation: once a popular library arrives, it’s almost impossible for new rivals to spread without everyone rewriting their code. And yes, the author swears “no LLMs” wrote it—humans brought the heat.
The flashpoint is the “orphan rule,” a safety rule that says you can only attach new behavior to types you own, not to someone else’s. Supporters say it prevents chaos—like two different definitions for how to store something in a map—while critics see a purity crusade that blocks practical progress. One camp, like user dathinab, insists these rules have “majorly contributed” to Rust’s quality. Across the aisle, nmilo went full flamethrower, calling it “purism and perfectionism” that “torpedo” the ecosystem, and begging for a big red “dangerously-disable” switch.
Others tried to cool things off with workarounds. ekidd rolled in with the classic fix: wrap the type in your own “gift box,” then you can add the behavior you need. Meanwhile, drive‑by quips like grougnax’s “you do not understand Rust” poured gasoline on the thread. Bonus drama: theoretical proposals about naming implementations were dunked on as pointless.
Result: a classic Rust split—Team Safety vs. Team Ship‑It—with memes about gatekeeping, crab fights, and “wrap it or scrap it” flying all day. Want stability or agility? In this thread, you can’t have both—pick a side.
Key Points
- •The article argues Rust’s coherence and orphan rules hinder ecosystem evolution by limiting who can implement traits for which types.
- •Foundational crates like serde create lock-in; alternatives require widespread additional implementations across many crates.
- •Coherence ensures a trait is implemented at most once for a given type/generics, preventing overlapping impls (error E0119).
- •The orphan rules restrict trait implementations to cases with a local trait or local type, blocking cross-crate external trait/type impls (error E0117).
- •Coherence is motivated by avoiding inconsistent behavior, illustrated by a HashSet example where multiple Hash impls could cause conflicts across crates.