Advanced everything in Go & Rust, page 4
Go's GC: Low-Latency Collection with Tri-color Marking
Go's GC uses a tri-color algorithm to find unused memory concurrently, avoiding long pauses. It's crucial for low-latency services. The main footgun is breaking the invariant: a 'finished' (black) object must never point to a new (white) one without notifying…
Rust Cargo Workspaces: A Monorepo Control Panel
A Cargo Workspace is a control panel for a multi-crate Rust project, unifying dependencies and build artifacts. Use it for related binaries and libraries to ensure consistent builds.
Go's `internal` Directory: Private by Convention
Go's internal directory creates private packages within your module, making them inaccessible to external projects. Use it for helper logic you don't want to support as a public API.
Rust's Arc<T>: Share Data Ownership Across Threads
Rust's Arc<T> lets multiple threads share ownership of heap data. It's a smart pointer that counts references atomically. Use it for shared caches or config. The footgun: Arc only makes sharing safe, not mutation—you still need a Mutex for that.
Rust's Rc<T>: Shared Ownership on a Single Thread
Rust's Rc<T> enables shared ownership within a single thread. Think of it as a counter on a heap-allocated resource: cloning an Rc increments the count, and the resource is freed only when the count hits zero. Use it for graph nodes with multiple owners.
Go's sync.Map: A Specialized Concurrent Map
Go's sync.Map is a concurrent map optimized for keys written once and read many times. It's ideal for long-lived caches, but it's not a generic replacement for a map with a mutex. The footgun is using it for frequent writes, which can be slower.
Using Box<T> for Heap Allocation in Rust
Rust's Box<T> is a smart pointer that moves data from the stack to the heap. It's essential for creating recursive types, like linked lists, whose size would otherwise be infinite. The main footgun is in FFI: never wrap a C-allocated pointer in a Box.
Rust's Turbofish (`::<>`): When the Compiler Needs Help
The turbofish (::<>) is your tool to resolve ambiguity when Rust's compiler can't infer a type or trait. Use it when a type implements multiple traits with same-named methods, forcing the compiler to pick the one you specify.
Zero-Cost Abstractions: Pay at Compile Time, Not Runtime
Zero-cost abstractions let you write high-level code that compiles to the same machine code as low-level optimizations. This is key in Rust for safe APIs without runtime overhead.
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