Introduction

MVX is a native compiler and runtime environment for Pick/MultiValue BASIC. It compiles BASIC straight to machine code through LLVM — no transpilation to C — and surrounds the compiler with the pieces that make a MultiValue system a system: a pluggable storage layer, a classic TCL shell, dictionaries and queries, secondary indexes, a package ecosystem, and full-screen terminal support.

The reference dialect is traditional Pick BASIC (classic Pick / R83 style). Wherever MultiValue platforms diverge, classic Pick behaviour is the tie-breaker. Extensions are admitted only where classic Pick has no equivalent, and each is documented as such — the two most visible being C-style comments and the modern terminal primitives.

Highlights:

• A real compiler. Programs and subroutines compile to native executables and shared libraries with DWARF debug information mapped to BASIC source lines — lldb sets breakpoints like b prog.b:12. Numeric code compiles to native integer and floating-point instructions; the standard prime-sieve benchmark runs at ~99% of an equivalent C program.
• Pluggable storage. MV files bind to backends through a small driver contract. Local ones: SQLite (the default), embedded LMDB, and plain directories (attributes as lines — the git-friendly shape). Networked ones: Postgres, MySQL and MongoDB, reached through a named connection profile so the committed binding never holds an address. Moving a file between them is CONVERT-FILE; a whole account, CONVERT-ACCOUNT.
• The classic environment. TCL with VOC dispatch, LIST/SELECT queries driven by dictionaries, select lists that flow between commands, ED, and the full verb set — with all verbs written in MVX BASIC itself.
• An ecosystem. Packages with dependency manifests, a Cobra-style command framework, runtime-resolved subroutine libraries, docblock metadata queryable through the dictionary, and a VSCode extension.

Where things live

mvx-basic	compiler and link driver
mvx	the classic TCL shell
mvx-msgd	the session registry and message daemon
verbs/	standard verbs (BASIC source)
packages/	shipped packages: cmd, git, sample
examples/	FSDEMO, SNAKE
ARCHITECTURE.md	the full design document
DECISIONS.md	settled implementation decisions