<!-- XDL: Chemical Description Language -->
<Synthesis>
  <Hardware>
    <Reactor id="reactor1" volume="100 mL"/>
    <Filter id="filter1"/>
    <Separator id="sep1"/>
  </Hardware>
  
  <Procedure>
    <Add reagent="A" vessel="reactor1" amount="10 mmol"/>
    <Add reagent="B" vessel="reactor1" amount="12 mmol"/>
    <HeatChill vessel="reactor1" temp="80 °C" time="2 h"/>
    <Filter from="reactor1" to="filter1"/>
  </Procedure>
</Synthesis>

def compile_xdl(xdl: str) -> HardwareInstructions:
    """Chempiler: XDL → executable hardware program."""
    tree = parse_xdl(xdl)
    graph = build_synthesis_graph(tree)
    return optimize_and_schedule(graph)

class XDLProgram:
    def __init__(self):
        self.steps = []
    
    def add(self, reagent: str, vessel: str, amount: str):
        self.steps.append(Add(reagent, vessel, amount))
    
    def heat(self, vessel: str, temp: str, time: str):
        self.steps.append(HeatChill(vessel, temp, time))
    
    def filter(self, from_vessel: str, to_vessel: str):
        self.steps.append(Filter(from_vessel, to_vessel))
    
    def loop(self, times: int, body: list):
        """Turing-complete: iteration."""
        self.steps.append(Loop(times, body))
    
    def conditional(self, sensor: str, threshold: float, then: list, else_: list):
        """Turing-complete: branching."""
        self.steps.append(Conditional(sensor, threshold, then, else_))

class Chemputer:
    def __init__(self, hardware_graph: nx.DiGraph):
        self.graph = hardware_graph
        self.state = ChemicalState()
    
    def execute(self, program: XDLProgram):
        """Execute XDL on hardware."""
        for step in program.steps:
            self.validate_hardware(step)
            self.execute_step(step)
            self.update_state(step)
    
    def validate_hardware(self, step):
        """Check hardware connectivity and capacity."""
        if not self.graph.has_path(step.source, step.target):
            raise HardwareError("No fluidic path")

def optimize_synthesis(xdl: XDLProgram) -> XDLProgram:
    """Optimize for time, yield, and hardware utilization."""
    graph = to_dag(xdl)
    
    # Parallelize independent operations
    parallel = find_parallel_steps(graph)
    
    # Minimize transfers
    optimized = minimize_transfers(graph)
    
    # Schedule for hardware
    return schedule(optimized, hardware_constraints)

# Compile XDL to hardware
just chemputer-compile synthesis.xdl

# Validate hardware graph
just chemputer-validate hardware.json

# Simulate synthesis
just chemputer-simulate synthesis.xdl --dry-run

# Execute on hardware
just chemputer-execute synthesis.xdl --hardware lab1

assembly-index (-1) ⊗ turing-chemputer (0) ⊗ crn-topology (+1) = 0 ✓  [Molecular Complexity]
kolmogorov-compression (-1) ⊗ turing-chemputer (0) ⊗ dna-origami (+1) = 0 ✓  [Self-Assembly]
persistent-homology (-1) ⊗ turing-chemputer (0) ⊗ crn-topology (+1) = 0 ✓  [Topological CRN]