Field Projections — Making Custom Pointers feel Builtin

Field Projections — Making Custom Pointers feel Builtin by Benno Lossin and Nadri. Rust makes heavy use of custom pointers filling the gap (& going beyond) between references (`&T` and `&mut T`) and raw pointers (`*const T` and `*mut T`). Currently, they have two major issues: ergonomics and feature parity with builtin references and `Box T`. Raw pointers and their extensions (e.g. `NonNull T`) have especially bad ergonomics. We are working on proposing the Field Projection language feature that aims to remedy these shortcomings of custom (dumb & smart) pointers. Our current approach is an ambitious generalization of `Deref` that supports a plethora of custom pointers from `MyBox T` (that has *all* the properties of `Box T`) to `VolatilePtr T` (which is only using `{read,write}_volatile` to access the pointee). Our proposal integrates tightly with existing features such as place expressions, operations on places, the borrow-checker, and autoref. Field Projections was a [project goal in 2025H2](https://rust-lang.github.io/rust-project-goals/2025h2/field-projections.html) and is very likely to [continue in 2026](https://rust-lang.github.io/rust-project-goals/2026/field-projections.html). In the last few months we have made incredible progress and want to involve greater parts of the community. About Benno Lossin (he/him): I started with Rust during university in 2021 and quickly fell in love with the language because of its type and trait system. In early 2022, I began my contributions to Rust for Linux, providing a solution to pinned initialization, which I maintain to this day. I then continued to review core Rust code and involved myself more with the development of Rust itself. Now I'm working mostly on field projections, in-place initialization, and various other language features. - git: https://github.com/BennoLossin - website: https://bennolossin.github.io/blog About Nadri (he/him): I'm a programming languages enthusiast and experienced Rust contributor. I fell in love with Rust for its cool design ideas and open governance, then started contributing in 2019 to scratch an itch and ended up the de-facto expert on pattern-matching. Since then I've been dabbling in lang design, opsem, spec and more recently type system work. In my dayjob I'm a research engineer working on a Rust analysis toolchain. - website: https://nadrieril.github.io/blog/ This talk was given at RustWeek 2026 as part of the Rust Project track on Wednesday 20 May. You can find a playlist of all talks in this track at https://www.youtube.com/playlist?list=PL8Q1w7Ff68DBkk0ddSEqdf97swuDvMSKS, and a playlist of all RustWeek 2026 talks at https://www.youtube.com/playlist?list=PL8Q1w7Ff68DBpmF38rcIAf8Z9Gj2TnlgM For information about RustWeek 2027, go to https://2027.rustweek.org. We hope to see you there!