D Internals, Evolution and Community

49.1 Compiler and Runtime Architecture

The DMD frontend is written in D (self-hosted since 2.069). It's shared by LDC and GDC.

druntime (core.*) and Phobos (std.*) are separate libraries.

Source → Lexer → Parser (AST) → Semantic analysis (3 passes: symbols, types, function bodies; CTFE interpreter; template instantiation)
       → Glue layer → Backend (DMD backend | LLVM (LDC) | GCC (GDC)) → Object files → Linker
Runtime: druntime (GC, TypeInfo, threads, exceptions, AA implementation, module ctors) + Phobos (stdlib)

49.2 Language Evolution

D1 (2001–2012) The original language (Tango vs Phobos split) const/immutable, ranges, templates/CTFE, pure, shared, Phobos 2

Self-hosted frontend, BetterC, static foreach, DIP1000 begins

Copy constructors, ImportC, std.sumtype, in parameters, shortened function syntax, interpolated strings (2.108)

DIP1000 progress, bitfields preview, placement new, editions preparation, move constructors work

Editions (opt-in language versions per module, e.g., safe-by-default), Phobos v3 (redesigned standard library, no autodecoding), improved GC, more ownership checks

Check dlang.org/changelog and the D Language Foundation's planning updates for the latest roadmap.

49.3 Community and Governance

The D Language Foundation (non-profit): DIP (D Improvement Proposal) process, quarterly planning, DConf (annual conference), the D blog.

Forums (forum.dlang.org), the Discord server, r/d_language, GitHub (dlang/dmd, dlang/phobos), the Bugzilla → GitHub Issues migration.

Contributing: build DMD from source (make -f posix.mak / build.d), run the test suite, pick "bootcamp" issues.