diff --git a/extra/gemm/tvm_gemm.py b/extra/gemm/tvm_gemm.py
new file mode 100644
index 0000000000..92c5b16b3d
--- /dev/null
+++ b/extra/gemm/tvm_gemm.py
@@ -0,0 +1,46 @@
+# https://tvm.apache.org/docs/tutorial/tensor_expr_get_started.html#example-2-manually-optimizing-matrix-multiplication-with-te
+import tvm
+from tvm import te
+#print(tvm.target.Target.list_kinds())
+
+M, N, K = 1024, 1024, 1024
+
+# c, opencl
+target = tvm.target.Target(target="c")
+
+# TVM Matrix Multiplication using TE
+k = te.reduce_axis((0, K), "k")
+A = te.placeholder((M, K), name="A")
+B = te.placeholder((K, N), name="B")
+C = te.compute((M, N), lambda x, y: te.sum(A[x, k] * B[k, y], axis=k), name="C")
+
+# Default schedule
+s = te.create_schedule(C.op)
+#print(tvm.lower(s, [A, B, C], simple_mode=True))
+
+# Output C code
+func = tvm.build(s, [A, B, C], target=target, name="mmult")
+print(func.get_source())
+
+# tinygrad version
+
+import os
+from tinygrad.tensor import Tensor
+
+# disable optimizations
+os.environ["NOOPT"] = "1"
+
+# define the compute
+A = Tensor.rand(M, K, device="clang")
+B = Tensor.rand(K, N, device="clang")
+C = (A.reshape(M, 1, K) * B.permute(1,0).reshape(1, N, K)).sum(axis=2)
+
+# capture the kernel. TODO: https://github.com/tinygrad/tinygrad/issues/1812
+from tinygrad.jit import CacheCollector
+CacheCollector.start()
+C.realize()
+result = CacheCollector.finish()
+
+print(result[0][0].prg)
+
+
diff --git a/tinygrad/codegen/kernel.py b/tinygrad/codegen/kernel.py
index 216630277b..49fb5eb1a4 100644
--- a/tinygrad/codegen/kernel.py
+++ b/tinygrad/codegen/kernel.py
@@ -23,10 +23,10 @@ class LinearizerOptions(NamedTuple):
   local_max: Optional[List[int]] = None
 
 class Kernel:
-  def __init__(self, ast:LazyOp, output_buffer:LazyBuffer, opts:LinearizerOptions):
+  def __init__(self, ast:LazyOp, output_buffer:LazyBuffer, opts:Optional[LinearizerOptions]=None):
     # NOTE: if there's a RESHAPE, we skip it. the output shape is set from the reduce op or a latebuf
     self.ast = ast.src[0] if ast.op == MovementOps.RESHAPE else ast
-    self.opts = opts
+    self.opts = opts if opts else LinearizerOptions()
 
     # get the output buffers
     self.bufs = [output_buffer] + dedup(ast.buffers)
diff --git a/tinygrad/renderer/cstyle.py b/tinygrad/renderer/cstyle.py
index 19a481127e..1645d7bc7e 100644
--- a/tinygrad/renderer/cstyle.py
+++ b/tinygrad/renderer/cstyle.py
@@ -79,7 +79,7 @@ class CStyleLanguage(NamedTuple):
     buftypes = [(name,f"{'read_only' if i > 0 else 'write_only'} image2d_t" if dtype.name.startswith('image') else
                 self.arg_int_prefix if dtype == dtypes._arg_int32 else
                 ("const " if i > 0 else "")+self.buffer_prefix+dtype.name+"*"+self.buffer_suffix) for i,(name,dtype) in enumerate(bufs)]
-    prg = ''.join([f"{self.kernel_prefix} void {f'__launch_bounds__ ({prod(local_size)}, 1) ' if self.launch_bounds else ''}{function_name}(",] +
+    prg = ''.join([f"{self.kernel_prefix}void {f'__launch_bounds__ ({prod(local_size)}, 1) ' if self.launch_bounds else ''}{function_name}(",] +
     [', '.join([f'{t} {name}' for name,t in buftypes] + self.extra_args)] +
     [") {\n" + tmp] + ['\n'.join(kernel), "\n}"])
     if self.half_prekernel and any(dtype == dtypes.float16 for _,dtype in bufs): prg = ''.join([f"{self.half_prekernel}", "\n", prg])
@@ -101,7 +101,7 @@ def uops_to_cstyle(lang:CStyleLanguage, function_name:str, uops:List[UOp]) -> st
   kernel,prekernel = [],[]
   #pend_close = None
   bufs = []
-  depth = 0
+  depth = 1
   def kk(s): kernel.append("  "*depth+s)
 
   c: DefaultDict[str, int] = defaultdict(int)
diff --git a/tinygrad/runtime/ops_clang.py b/tinygrad/runtime/ops_clang.py
index bb53ab7a94..2959f75634 100644
--- a/tinygrad/runtime/ops_clang.py
+++ b/tinygrad/runtime/ops_clang.py
@@ -12,7 +12,7 @@ ARM64 = getenv('ARM64', False)
 if CI and ARM64: from unicorn import Uc, UC_ARCH_ARM64, UC_MODE_ARM, UC_HOOK_CODE, arm64_const   # type: ignore
 
 args = {
-  'Windows': {'cflags':'', 'ext':'dll', 'exp':'__declspec(dllexport)'},
+  'Windows': {'cflags':'', 'ext':'dll', 'exp':'__declspec(dllexport) '},
   'Linux': {'cflags':'-lm -fPIC --rtlib=compiler-rt ', 'ext':'so', 'exp':''},
   'Darwin': {'cflags':'-lm -fPIC --rtlib=compiler-rt ', 'ext':'dylib', 'exp':''}
 }[platform.system()]
diff --git a/tinygrad/runtime/ops_cuda.py b/tinygrad/runtime/ops_cuda.py
index 88eac03ccf..68d2a1d8ba 100644
--- a/tinygrad/runtime/ops_cuda.py
+++ b/tinygrad/runtime/ops_cuda.py
@@ -86,7 +86,7 @@ class CUDAProgram:
       return start.time_till(end)*1e-3
 
 renderer = functools.partial(uops_to_cstyle, CStyleLanguage(
-  kernel_prefix = "__global__", smem_prefix = "__shared__ ", arg_int_prefix = "const int", barrier = "__syncthreads();", float4 = "make_float4",
+  kernel_prefix = "__global__ ", smem_prefix = "__shared__ ", arg_int_prefix = "const int", barrier = "__syncthreads();", float4 = "make_float4",
   gid = [f'blockIdx.{chr(120+i)}' for i in range(3)],
   lid = [f'threadIdx.{chr(120+i)}' for i in range(3)],
   half_prekernel = """
diff --git a/tinygrad/runtime/ops_gpu.py b/tinygrad/runtime/ops_gpu.py
index 656defc468..23310dd7e3 100644
--- a/tinygrad/runtime/ops_gpu.py
+++ b/tinygrad/runtime/ops_gpu.py
@@ -104,7 +104,7 @@ class CLProgram:
     return None
 
 renderer = functools.partial(uops_to_cstyle, CStyleLanguage(
-  kernel_prefix = "__kernel", buffer_prefix = "__global ", smem_prefix = "__local ", arg_int_prefix = "const int",
+  kernel_prefix = "__kernel ", buffer_prefix = "__global ", smem_prefix = "__local ", arg_int_prefix = "const int",
   half_prekernel = "#pragma OPENCL EXTENSION cl_khr_fp16 : enable",
   barrier = "barrier(CLK_LOCAL_MEM_FENCE);", float4 = "(float4)",
   gid = [f'get_group_id({i})' for i in range(3)], lid = [f'get_local_id({i})' for i in range(3)], uses_vload=True))
diff --git a/tinygrad/runtime/ops_metal.py b/tinygrad/runtime/ops_metal.py
index fffae4ba34..efc9e56d9f 100644
--- a/tinygrad/runtime/ops_metal.py
+++ b/tinygrad/runtime/ops_metal.py
@@ -81,7 +81,7 @@ class MetalProgram:
     METAL.mtl_buffers_in_flight.append(command_buffer)
 
 renderer = functools.partial(uops_to_cstyle, CStyleLanguage(
-  kernel_prefix = "#include <metal_stdlib>\nusing namespace metal;\nkernel", buffer_prefix = "device ", smem_prefix = "threadgroup ", arg_int_prefix = "constant int&",
+  kernel_prefix = "#include <metal_stdlib>\nusing namespace metal;\nkernel ", buffer_prefix = "device ", smem_prefix = "threadgroup ", arg_int_prefix = "constant int&",
   barrier = "threadgroup_barrier(mem_flags::mem_threadgroup);", float4 = "float4", uses_ptr_arithmetic=True,
   gid = [f"gid.{chr(120+i)}" for i in range(3)], lid = [f"lid.{chr(120+i)}" for i in range(3)],
   extra_args = ['uint3 gid [[threadgroup_position_in_grid]]', 'uint3 lid [[thread_position_in_threadgroup]]']))