diff --git a/script/to_html.sh b/script/to_html.sh
new file mode 100755
index 000000000..0e377a668
--- /dev/null
+++ b/script/to_html.sh
@@ -0,0 +1,5 @@
+#!/bin/bash
+#nvim -c ":TOhtml" $1
+sed -i "s/PreProc { color: #5fd7ff; }/PreProc { color: #8f2722; }/" $1
+sed -i "s/Comment { color: #00ffff; }/Comment { color: #0055ff; }/" $1
+
diff --git a/script/zk.vim b/script/zk.vim
new file mode 100644
index 000000000..4c5b43d59
--- /dev/null
+++ b/script/zk.vim
@@ -0,0 +1,41 @@
+"For autoload, add this to your VIM config:
+"   VIM:    .vimrc
+"   NeoVIM: .config/nvim/init.vim
+"
+"autocmd BufRead *.pism call SetPismOptions()
+"function SetPismOptions()
+"    set syntax=pism
+"    source /home/narodnik/src/drk/scripts/pism.vim
+"endfunction
+
+if exists('b:current_syntax')
+    finish
+endif
+
+syn keyword drkKeyword constant contract circuit
+"syn keyword drkAttr
+syn keyword drkType EcFixedPoint Base Scalar
+"syn keyword drkFunctionKeyword enforce lc0_add_one lc1_add_one lc2_add_one lc_coeff_reset lc_coeff_double lc0_sub_one lc1_sub_one lc2_sub_one dump_alloc dump_local
+syn match drkFunction "^[ ]*[a-z_0-9]* "
+syn match drkComment "#.*$"
+syn match drkNumber ' \zs\d\+\ze'
+syn match drkHexNumber ' \zs0x[a-z0-9]\+\ze'
+syn match drkConst '[A-Z_]\{2,}[A-Z0-9_]*'
+syn keyword drkBoolVal true false
+syn match drkPreproc "{%.*%}"
+syn match drkPreproc2 "{{.*}}"
+
+hi def link drkKeyword    Statement
+"hi def link drkAttr       StorageClass
+hi def link drkPreproc    PreProc
+hi def link drkPreproc2   PreProc
+hi def link drkType       Type
+hi def link drkFunction   Function
+hi def link drkFunctionKeyword Function
+hi def link drkComment    Comment
+hi def link drkNumber     Constant
+hi def link drkHexNumber  Constant
+hi def link drkConst      Constant
+hi def link drkBoolVal    Constant
+
+let b:current_syntax = "pism"
diff --git a/script/zkas.py b/script/zkas.py
new file mode 100644
index 000000000..a729762ad
--- /dev/null
+++ b/script/zkas.py
@@ -0,0 +1,402 @@
+import argparse
+import sys
+
+from zkas.types import *
+
+class CompileException(Exception):
+
+    def __init__(self, error_message, line):
+        super().__init__(error_message)
+        self.error_message = error_message
+        self.line = line
+
+class Constants:
+
+    def __init__(self):
+        self.table = []
+        self.map = {}
+
+    def add(self, variable, type_id):
+        idx = len(self.table)
+        self.table.append(type_id)
+        self.map[variable] = idx
+
+    def lookup(self, variable):
+        idx = self.map[variable]
+        return self.table[idx]
+
+    def variables(self):
+        return self.map.keys()
+
+class SyntaxStruct:
+
+    def __init__(self):
+        self.contracts = {}
+        self.circuits = {}
+        self.constants = Constants()
+
+    def parse_contract(self, line, it):
+        assert line.tokens[0] == "contract"
+        if len(line.tokens) != 3 or line.tokens[2] != "{":
+            raise CompileException("malformed contract opening", line)
+        name = line.tokens[1]
+        if name in self.contracts:
+            raise CompileException(f"duplicate contract {name}", line)
+        lines = []
+
+        while True:
+            try:
+                line = next(it)
+            except StopIteration:
+                raise CompileException(
+    f"premature end of file while parsing {name} contract", line)
+
+            assert len(line.tokens) > 0
+            if line.tokens[0] == "}":
+                break
+
+            lines.append(line)
+
+        self.contracts[name] = lines
+
+    def parse_circuit(self, line, it):
+        assert line.tokens[0] == "circuit"
+        if len(line.tokens) != 3 or line.tokens[2] != "{":
+            raise CompileException("malformed circuit opening", line)
+        name = line.tokens[1]
+        if name in self.circuits:
+            raise CompileException(f"duplicate contract {name}", line)
+        lines = []
+
+        while True:
+            try:
+                line = next(it)
+            except StopIteration:
+                raise CompileException(
+    f"premature end of file while parsing {name} circuit", line)
+
+            assert len(line.tokens) > 0
+            if line.tokens[0] == "}":
+                break
+
+            lines.append(line)
+
+        self.circuits[name] = lines
+
+    def parse_constant(self, line):
+        assert line.tokens[0] == "constant"
+        if len(line.tokens) != 3:
+            raise CompileException("malformed constant line", line)
+        _, type_name, variable = line.tokens
+        if type_name not in allowed_types:
+            raise CompileException("unknown type '{type}'", line)
+        type_id = allowed_types[type_name]
+        self.constants.add(variable, type_id)
+
+    def verify(self):
+        self.static_checks()
+        schema = self.format_data()
+        self.trace_circuits(schema)
+        return schema
+
+    def static_checks(self):
+        for name, lines in self.contracts.items():
+            for line in lines:
+                if len(line.tokens) != 2:
+                    raise CompileException("incorrect number of tokens", line)
+                type, variable = line.tokens
+                if type not in allowed_types:
+                    raise CompileException(
+                        f"unknown type specifier for variable {variable}", line)
+
+        for name, lines in self.circuits.items():
+            for line in lines:
+                assert len(line.tokens) > 0
+                func_name, args = line.tokens[0], line.tokens[1:]
+                if func_name not in function_formats:
+                    raise CompileException(f"unknown function call {func_name}",
+                                         line)
+                func_format = function_formats[func_name]
+                if len(args) != func_format.total_arguments():
+                    raise CompileException(
+        f"incorrect number of arguments for function call {func_name}", line)
+
+        # Finally check there are matching circuits and contracts
+        all_names = set(self.circuits.keys()) | set(self.contracts.keys())
+
+        for name in all_names:
+            if name not in self.contracts:
+                raise CompileException(f"missing contract for {name}", None)
+            if name not in self.circuits:
+                raise CompileException(f"missing circuit for {name}", None)
+
+    def format_data(self):
+        schema = []
+        for name, circuit in self.circuits.items():
+            assert name in self.contracts
+            contract = self.contracts[name]
+
+            witness = []
+            for line in contract:
+                assert len(line.tokens) == 2
+                type_name, variable = line.tokens
+                assert type_name in allowed_types
+                type_id = allowed_types[type_name]
+                witness.append((type_id, variable, line))
+
+            code = []
+            for line in circuit:
+                assert len(line.tokens) > 0
+                func_name, args = line.tokens[0], line.tokens[1:]
+                assert func_name in function_formats
+                func_format = function_formats[func_name]
+                assert len(args) == func_format.total_arguments()
+
+                return_values = []
+                if func_format.return_type_ids:
+                    rv_len = len(func_format.return_type_ids)
+                    return_values, args = args[:rv_len], args[rv_len:]
+
+                func_id = func_format.func_id
+                code.append((func_format, return_values, args, line))
+
+            schema.append((name, witness, code))
+        return schema
+
+    def trace_circuits(self, schema):
+        for name, witness, code in schema:
+            tracer = DynamicTracer(name, witness, code, self.constants)
+            tracer.execute()
+
+class DynamicTracer:
+
+    def __init__(self, name, contract_witness, circuit_code, constants):
+        self.name = name
+        self.witness = contract_witness
+        self.code = circuit_code
+        self.constants = constants
+
+    def execute(self):
+        stack = {}
+
+        # Load constants
+        for variable in self.constants.variables():
+            stack[variable] = self.constants.lookup(variable)
+
+        # Preload stack with our witness values
+        for type_id, variable, line in self.witness:
+            stack[variable] = type_id
+
+        for i, (func_format, return_values, args, code_line) \
+            in enumerate(self.code):
+
+            assert len(args) == len(func_format.param_types)
+            for variable, type_id in zip(args, func_format.param_types):
+                if variable not in stack:
+                    raise CompileException(
+                        f"variable '{variable}' is not defined", code_line)
+
+                stack_type_id = stack[variable]
+                if stack_type_id != type_id:
+                    type_name = type_id_to_name[type]
+                    stack_type_name = type_id_to_name[stack_type]
+                    raise CompileException(
+    f"variable '{variable}' has incorrect type. "
+    f"Found {type_name} but expected variable of "
+    f"type {stack_type_name}", code_line)
+
+                assert len(return_values) == len(func_format.return_type_ids)
+
+                for return_variable, return_type_id \
+                    in zip(return_values, func_format.return_type_ids):
+
+                    # Note that later variables shadow earlier ones.
+                    # We accept this.
+
+                    stack[return_variable] = return_type_id
+
+class CodeLine:
+
+    def __init__(self, func_format, return_values, args, arg_idxs, code_line):
+        self.func_format = func_format
+        self.return_values = return_values
+        self.args = args
+        self.arg_idxs = arg_idxs
+        self.code_line = code_line
+
+    def func_name(self):
+        return func_id_to_name[self.func_format.func_id]
+
+class CompiledContract:
+
+    def __init__(self, name, witness, code):
+        self.name = name
+        self.witness = witness
+        self.code = code
+
+class Compiler:
+
+    def __init__(self, witness, uncompiled_code, constants):
+        self.witness = witness
+        self.uncompiled_code = uncompiled_code
+        self.constants = constants
+
+    def compile(self):
+        code = []
+
+        # Each unique type_id has its own stack
+        stacks = [[] for i in range(TYPE_ID_LAST)]
+        # Map from variable name to stacks above
+        stack_vars = {}
+
+        def alloc(variable, type_id):
+            assert type_id <= len(stacks)
+            idx = len(stacks[type_id])
+            # Add variable to the stack for its type_id
+            stacks[type_id].append(variable)
+            # Create mapping from variable name
+            stack_vars[variable] = (type_id, idx)
+
+        # Load constants
+        for variable in self.constants.variables():
+            type_id = self.constants.lookup(variable)
+            alloc(variable, type_id)
+
+        # Preload stack with our witness values
+        for type_id, variable, line in self.witness:
+            alloc(variable, type_id)
+
+        for i, (func_format, return_values, args, code_line) \
+            in enumerate(self.uncompiled_code):
+
+            assert len(args) == len(func_format.param_types)
+
+            arg_idxs = []
+
+            # Loop through all arguments
+            for variable, type_id in zip(args, func_format.param_types):
+                assert type_id <= len(stacks)
+                assert variable in stack_vars
+                # Find the index for the M by N matrix of our variable
+                loc_type_id, loc_idx = stack_vars[variable]
+                assert type_id == loc_type_id
+                assert stacks[loc_type_id][loc_idx] == variable
+
+                # This is the info to be serialized, not the variable names
+                arg_idxs.append(loc_idx)
+
+            assert len(return_values) == len(func_format.return_type_ids)
+
+            for return_variable, return_type_id \
+                in zip(return_values, func_format.return_type_ids):
+
+                # Allocate returned values so they can be used by
+                # subsequent function calls.
+                alloc(return_variable, return_type_id)
+
+            code.append(CodeLine(func_format, return_values, args,
+                                 arg_idxs, code_line))
+
+        return code
+
+class Line:
+
+    def __init__(self, tokens, original_line, number):
+        self.tokens = tokens
+        self.orig = original_line
+        self.number = number
+
+    def __repr__(self):
+        return f"Line({self.number}: {str(self.tokens)})"
+
+def load(src_file):
+    source = []
+    for i, original_line in enumerate(src_file):
+        # Remove whitespace on both sides
+        line = original_line.strip()
+        # Strip out comments
+        line = line.split("#")[0]
+        # Split at whitespace
+        line = line.split()
+        if not line:
+            continue
+        line_number = i + 1
+        source.append(Line(line, original_line, line_number))
+    return source
+
+def parse(source):
+    syntax = SyntaxStruct()
+    it = iter(source)
+    while True:
+        try:
+            line = next(it)
+        except StopIteration:
+            break
+
+        assert len(line.tokens) > 0
+        if line.tokens[0] == "contract":
+            syntax.parse_contract(line, it)
+        elif line.tokens[0] == "circuit":
+            syntax.parse_circuit(line, it)
+        elif line.tokens[0] == "constant":
+            syntax.parse_constant(line)
+        elif line.tokens[0] == "}":
+            raise CompileException("unmatched delimiter '}'", line)
+    return syntax
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument("SOURCE", help="ZK script to compile")
+    parser.add_argument("--output", default=None, help="output file")
+    group = parser.add_mutually_exclusive_group()
+    group.add_argument('--display', action='store_true',
+                       help="show the compiled code in human readable format")
+    group.add_argument('--bincode', action='store_true',
+                       help="output compiled code to zkvm supervisor")
+    args = parser.parse_args()
+
+    with open(args.SOURCE, "r") as src_file:
+        source = load(src_file)
+    try:
+        syntax = parse(source)
+        schema = syntax.verify()
+        contracts = []
+        for name, witness, uncompiled_code in schema:
+            compiler = Compiler(witness, uncompiled_code, syntax.constants)
+            code = compiler.compile()
+            contracts.append(CompiledContract(name, witness, code))
+        constants = syntax.constants
+        if args.display:
+            from zkas.text_output import output
+            if args.output is None:
+                output(sys.stdout, contracts, constants)
+            else:
+                with open(outpath, "w") as file:
+                    output(file, contracts, constants)
+        elif args.bincode:
+            from zkas.bincode_output import output
+            outpath = args.output
+            if args.output is None:
+                outpath = args.SOURCE + ".bin"
+            with open(outpath, "wb") as file:
+                output(file, contracts, constants)
+        else:
+            from zkas.text_output import output
+            if args.output is None:
+                output(sys.stdout, contracts, constants)
+            else:
+                with open(outpath, "w") as file:
+                    output(file, contracts, constants)
+    except CompileException as ex:
+        print(f"Error: {ex.error_message}", file=sys.stderr)
+        if ex.line is not None:
+            print(f"Line {ex.line.number}: {ex.line.orig}", file=sys.stderr)
+        #return -1
+        raise
+    return 0
+
+if __name__ == "__main__":
+    sys.exit(main())
+
+# todo: think about extendable payment scheme which
+# is like bitcoin soft forks
diff --git a/script/zkas/__init__.py b/script/zkas/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/script/zkas/bincode_output.py b/script/zkas/bincode_output.py
new file mode 100644
index 000000000..4af5873c3
--- /dev/null
+++ b/script/zkas/bincode_output.py
@@ -0,0 +1,50 @@
+import struct
+
+def varuint(value):
+    if value <= 0xfc:
+        return struct.pack("<B", value)
+    elif value <= 0xffff:
+        return struct.pack("<BH", 0xfd, value)
+    elif value <= 0xffffffff:
+        return struct.pack("<BI", 0xfe, value)
+    else:
+        return struct.pack("<BQ", 0xff, value)
+
+def write_len(output, objects):
+    output.write(varuint(len(objects)))
+
+def write_value(fmt, output, value):
+    value_bytes = struct.pack("<" + fmt, value)
+    output.write(value_bytes)
+
+def write_u8(output, value):
+    write_value("B", output, value)
+def write_u32(output, value):
+    write_value("I", output, value)
+
+def output_contract(output, contract):
+    write_len(output, contract.name)
+    output.write(contract.name.encode())
+    write_len(output, contract.witness)
+    for type_id, variable, _ in contract.witness:
+        write_len(output, variable)
+        output.write(variable.encode())
+        write_u8(output, type_id)
+    write_len(output, contract.code)
+    for code in contract.code:
+        func_id = code.func_format.func_id
+        write_u8(output, func_id)
+        for arg_idx in code.arg_idxs:
+            write_u32(output, arg_idx)
+
+def output(output, contracts, constants):
+    write_len(output, constants.variables())
+    for variable in constants.variables():
+        write_len(output, variable)
+        output.write(variable.encode())
+        type_id = constants.lookup(variable)
+        write_u8(output, type_id)
+    write_len(output, contracts)
+    for contract in contracts:
+        output_contract(output, contract)
+
diff --git a/script/zkas/text_output.py b/script/zkas/text_output.py
new file mode 100644
index 000000000..9faa200d4
--- /dev/null
+++ b/script/zkas/text_output.py
@@ -0,0 +1,21 @@
+from .types import type_id_to_name, func_id_to_name
+
+def output(output, contracts, constants):
+    output.write("Constants:\n")
+    for variable in constants.variables():
+        type_id = constants.lookup(variable)
+        output.write(f"  {type_id} {variable}\n")
+    for contract in contracts:
+        output.write(f"{contract.name}:\n")
+
+        output.write(f"  Witness:\n")
+        for type_id, variable, _ in contract.witness:
+            type_name = type_id_to_name[type_id]
+            output.write(f"    {type_name} {variable}\n")
+
+        output.write(f"  Code:\n")
+        for code in contract.code:
+            output.write(f"    # args = {code.args}\n")
+            output.write(f"    {code.func_name()} {code.return_values} "
+                             f"{code.arg_idxs}\n")
+
diff --git a/script/zkas/types.py b/script/zkas/types.py
new file mode 100644
index 000000000..610a9a61d
--- /dev/null
+++ b/script/zkas/types.py
@@ -0,0 +1,69 @@
+TYPE_ID_BASE                    = 0
+TYPE_ID_SCALAR                  = 1
+TYPE_ID_EC_POINT                = 2
+TYPE_ID_EC_FIXED_POINT          = 3
+# This is so we know the number of TYPE_ID stacks
+TYPE_ID_LAST                    = 4
+
+allowed_types = {
+    "Base":                 TYPE_ID_BASE,
+    "Scalar":               TYPE_ID_SCALAR,
+    "EcFixedPoint":         TYPE_ID_EC_FIXED_POINT
+}
+# Used for debug and error messages
+type_id_to_name = dict((value, key) for key, value in allowed_types.items())
+
+FUNC_ID_POSEIDON_HASH           = 0
+FUNC_ID_ADD                     = 1
+FUNC_ID_CONSTRAIN_INSTANCE      = 2
+FUNC_ID_EC_MUL_SHORT            = 3
+FUNC_ID_EC_MUL                  = 4
+FUNC_ID_EC_ADD                  = 5
+FUNC_ID_EC_GET_X                = 6
+FUNC_ID_EC_GET_Y                = 7
+
+class FuncFormat:
+
+    def __init__(self, func_id, return_type_ids, param_types):
+        self.func_id = func_id
+        self.return_type_ids = return_type_ids
+        self.param_types = param_types
+
+    def total_arguments(self):
+        return len(self.return_type_ids) + len(self.param_types)
+
+function_formats = {
+    "poseidon_hash": FuncFormat(
+        # Funcion ID            Type ID             Parameter types
+        FUNC_ID_POSEIDON_HASH,  [TYPE_ID_BASE],     [TYPE_ID_BASE,
+                                                     TYPE_ID_BASE]
+    ),
+    "add": FuncFormat(
+        FUNC_ID_ADD,            [TYPE_ID_BASE],     [TYPE_ID_BASE,
+                                                     TYPE_ID_BASE]
+    ),
+    "constrain_instance": FuncFormat(
+        FUNC_ID_CONSTRAIN_INSTANCE, [],             [TYPE_ID_BASE]
+    ),
+    "ec_mul_short": FuncFormat(
+        FUNC_ID_EC_MUL_SHORT,   [TYPE_ID_EC_POINT], [TYPE_ID_BASE,
+                                                     TYPE_ID_EC_FIXED_POINT]
+    ),
+    "ec_mul": FuncFormat(
+        FUNC_ID_EC_MUL,         [TYPE_ID_EC_POINT], [TYPE_ID_SCALAR,
+                                                     TYPE_ID_EC_FIXED_POINT]
+    ),
+    "ec_add": FuncFormat(
+        FUNC_ID_EC_ADD,         [TYPE_ID_EC_POINT], [TYPE_ID_EC_POINT,
+                                                     TYPE_ID_EC_POINT]
+    ),
+    "ec_get_x": FuncFormat(
+        FUNC_ID_EC_GET_X,       [TYPE_ID_BASE],     [TYPE_ID_EC_POINT]
+    ),
+    "ec_get_y": FuncFormat(
+        FUNC_ID_EC_GET_Y,       [TYPE_ID_BASE],     [TYPE_ID_EC_POINT]
+    ),
+}
+
+func_id_to_name = dict((fmt.func_id, key) for key, fmt
+                       in function_formats.items())