xquad is the Python distribution most users should install. It provides the interactive Program / Session / RunResult API, a unified VM wrapper that dispatches to either the Rust or Python interpreter, and re-exports the lower-level peer packages (xqffi, xqcp, xqsa) under a single namespace.

pip install xquad

Pulls xqffi, xqcp, xqsa, and xqvm_py as runtime dependencies. Peer installs stay valid (pip install xqffi xqcp xqsa) if you only need a subset.

Load a program once, run it with different calldata, inspect outputs by slot:

from xquad.program import Program

program = Program.from_source("""
PUSH 0
INPUT r0
PUSH 1
INPUT r1
LOAD r0
LOAD r1
ADD
STOW r2
PUSH 0
OUTPUT r2
HALT
""")

session = program.session(output_slots=1)
session.set_calldata([40, 2])
result = session.run()
assert dict(result.outputs) == {0: 42}

Program.load(bytes) takes wire-format bytecode; Session.run() returns a RunResult with dict-keyed outputs (unset slots present as None), residual stack, and step count.

Compile a problem via the DSL, execute, sample:

from xquad import cp, sa
from xquad.vm import VM, VMBackend

problem = cp.Problem("MyProblem")
# ... define inputs, model, objective, decoder ...
programs = problem.compile()

vm = VM(backend=VMBackend.RUST)   # or VMBackend.PYTHON for the reference interpreter
vm.set_output_slots(1)
vm.run(programs.encoder)
model = vm.outputs()[0]

sample = sa.SolverDWaveCPU().solve(model).sample

Re-exports of peer packages are identity, not copies:

import xquad, xqcp
assert xquad.cp.Problem is xqcp.Problem   # always True

So isinstance works whether the caller imported directly from the peer or via the umbrella.

Lower-level escape hatches remain available directly via the peer packages (xqffi.vm.Vm for the raw FFI one-shot surface; xqvm_py.Executor for the pure-Python reference VM).

• xqffi -- PyO3 FFI bindings (low-level / conformance).
• xqvm_py -- pure-Python reference VM (conformance oracle).
• xqcp -- constraint-programming DSL.
• xqsa -- solver adapters.
• Running Programs -- end-to-end tour including the Program/Session, xqffi.vm, and xquad.vm surfaces.

AGPL-3.0-or-later.