Installing D and DUB

To write and run D code you need a compiler (DMD, LDC, or GDC) and, for anything beyond a single file, DUB -- D's official package and build manager. DMD is the reference compiler maintained by the D Language Foundation and is the fastest to compile with, making it the default choice while learning; LDC (LLVM-based) and GDC (GCC-based) produce more optimized native binaries and are typically used for release builds or targets DMD doesn't support well, such as ARM or WebAssembly.

The simplest path on Linux or macOS is the official install script: curl -fsS https://dlang.org/install.sh | bash -s dmd, which downloads DMD, the standard library (Phobos), and the runtime (druntime) into a local directory and prints a source command to add them to your PATH. Windows users can grab the DMD installer (.exe) directly from dlang.org, or install via choco install dmd with Chocolatey; Linux users on Debian/Ubuntu can alternatively add the D APT repository, and macOS users can run brew install dmd. Once installed, dmd --version should print the compiler version, confirming the toolchain is on your PATH.

DUB is bundled with the official DMD installer and manages dependencies, build configurations, and project scaffolding much like npm for Node.js or cargo for Rust. Running dub init myproject scaffolds a new project with a dub.json (or dub.sdl) manifest describing the package name, dependencies, and target type; dub build compiles it, dub run compiles and executes it in one step, and dub add <package> fetches a dependency from the central registry at code.dlang.org and records it in dub.selections.json for reproducible builds.

After installing, create a throwaway file test.d containing a main() that calls writeln, then run it with rdmd test.d -- rdmd is a companion tool that compiles and immediately runs a single file without leaving a binary behind, ideal for quick checks and scripting. If rdmd reports "command not found," the install script's PATH export likely wasn't sourced in your current shell session; re-run the source line it printed, or add it to your .bashrc/.zshrc so it persists across terminal sessions.