diff --git a/gguf.py b/gguf.py
index 8e2c771ba..88e2bee07 100644
--- a/gguf.py
+++ b/gguf.py
@@ -61,98 +61,113 @@ class GGUFWriter:
     def __init__(self, fout: IO):
         self.fout = fout
         self.offset_tensor = 0
+        self.kv_data = b""
+        self.kv_data_count = 0
+        self.ti_data = b""
+        self.ti_data_count = 0
 
-    def write_header(self, tensor_count: int, metadata_kv_count: int):
+    def write_header_to_file(self):
         self.fout.write(struct.pack("<I", constants.GGUF_MAGIC))
         self.fout.write(struct.pack("<I", constants.GGUF_VERSION))
-        self.fout.write(struct.pack("<I", tensor_count))
-        self.fout.write(struct.pack("<I", metadata_kv_count))
+        self.fout.write(struct.pack("<I", self.ti_data_count))
+        self.fout.write(struct.pack("<I", self.kv_data_count))
+        self.flush()
+#        print("tensors " + str(self.ti_data_count) + " kv " + str(self.kv_data_count))
+
+    def write_kv_data_to_file(self):
+        self.fout.write(self.kv_data)
+        self.flush()
+
+    def write_ti_data_to_file(self):
+        self.fout.write(self.ti_data)
+        self.flush()
 
     @classmethod
     def open(cls, path: str) -> "GGUFWriter":
         f = open(path, "wb")
         return cls(f)
 
-    def write_key(self, key: str):
-        self.write_val(key, GGUFValueType.STRING, write_vtype=False)
+    def add_key(self, key: str):
+        self.add_val(key, GGUFValueType.STRING, add_vtype=False)
 
-    def write_uint8(self, key: str, val: int):
-        self.write_key(key)
-        self.write_val(val, GGUFValueType.UINT8)
+    def add_uint8(self, key: str, val: int):
+        self.add_key(key)
+        self.add_val(val, GGUFValueType.UINT8)
 
-    def write_int8(self, key: str, val: int):
-        self.write_key(key)
-        self.write_val(val, GGUFValueType.INT8)
+    def add_int8(self, key: str, val: int):
+        self.add_key(key)
+        self.add_val(val, GGUFValueType.INT8)
 
-    def write_uint16(self, key: str, val: int):
-        self.write_key(key)
-        self.write_val(val, GGUFValueType.UINT16)
+    def add_uint16(self, key: str, val: int):
+        self.add_key(key)
+        self.add_val(val, GGUFValueType.UINT16)
 
-    def write_int16(self, key: str, val: int):
-        self.write_key(key)
-        self.write_val(val, GGUFValueType.INT16)
+    def add_int16(self, key: str, val: int):
+        self.add_key(key)
+        self.add_val(val, GGUFValueType.INT16)
 
-    def write_uint32(self, key: str, val: int):
-        self.write_key(key)
-        self.write_val(val, GGUFValueType.UINT32)
+    def add_uint32(self, key: str, val: int):
+        self.add_key(key)
+        self.add_val(val, GGUFValueType.UINT32)
 
-    def write_int32(self, key: str, val: int):
-        self.write_key(key)
-        self.write_val(val, GGUFValueType.INT32)
+    def add_int32(self, key: str, val: int):
+        self.add_key(key)
+        self.add_val(val, GGUFValueType.INT32)
 
-    def write_float32(self, key: str, val: float):
-        self.write_key(key)
-        self.write_val(val, GGUFValueType.FLOAT32)
+    def add_float32(self, key: str, val: float):
+        self.add_key(key)
+        self.add_val(val, GGUFValueType.FLOAT32)
 
-    def write_bool(self, key: str, val: bool):
-        self.write_key(key)
-        self.write_val(val, GGUFValueType.BOOL)
+    def add_bool(self, key: str, val: bool):
+        self.add_key(key)
+        self.add_val(val, GGUFValueType.BOOL)
 
-    def write_string(self, key: str, val: str):
-        self.write_key(key)
-        self.write_val(val, GGUFValueType.STRING)
+    def add_string(self, key: str, val: str):
+        self.add_key(key)
+        self.add_val(val, GGUFValueType.STRING)
 
-    def write_array(self, key: str, val: list):
+    def add_array(self, key: str, val: list):
         if not isinstance(val, list):
             raise ValueError("Value must be a list for array type")
 
-        self.write_key(key)
-        self.write_val(val, GGUFValueType.ARRAY)
+        self.add_key(key)
+        self.add_val(val, GGUFValueType.ARRAY)
 
-    def write_val(self: str, val: Any, vtype: GGUFValueType = None, write_vtype: bool = True):
+    def add_val(self: str, val: Any, vtype: GGUFValueType = None, add_vtype: bool = True):
         if vtype is None:
             vtype = GGUFValueType.get_type(val)
 
-        if write_vtype:
-            self.fout.write(struct.pack("<I", vtype))
+        if add_vtype:
+            self.kv_data += struct.pack("<I", vtype)
+            self.kv_data_count += 1;
 
         if vtype == GGUFValueType.UINT8:
-            self.fout.write(struct.pack("<B", val))
+            self.kv_data += struct.pack("<B", val)
         elif vtype == GGUFValueType.INT8:
-            self.fout.write(struct.pack("<b", val))
+            self.kv_data += struct.pack("<b", val)
         elif vtype == GGUFValueType.UINT16:
-            self.fout.write(struct.pack("<H", val))
+            self.kv_data += struct.pack("<H", val)
         elif vtype == GGUFValueType.INT16:
-            self.fout.write(struct.pack("<h", val))
+            self.kv_data += struct.pack("<h", val)
         elif vtype == GGUFValueType.UINT32:
-            self.fout.write(struct.pack("<I", val))
+            self.kv_data += struct.pack("<I", val)
         elif vtype == GGUFValueType.INT32:
-            self.fout.write(struct.pack("<i", val))
+            self.kv_data += struct.pack("<i", val)
         elif vtype == GGUFValueType.FLOAT32:
-            self.fout.write(struct.pack("<f", val))
+            self.kv_data += struct.pack("<f", val)
         elif vtype == GGUFValueType.BOOL:
-            self.fout.write(struct.pack("?", val))
+            self.kv_data += struct.pack("?", val)
         elif vtype == GGUFValueType.STRING:
             encoded_val = val.encode("utf8") if isinstance(val, str) else val
-            self.fout.write(struct.pack("<I", len(encoded_val)))
-            self.fout.write(encoded_val)
+            self.kv_data += struct.pack("<I", len(encoded_val))
+            self.kv_data += encoded_val
         elif vtype == GGUFValueType.ARRAY:
             ltype = set([GGUFValueType.get_type(item) for item in val])
             assert len(ltype) == 1, "All items in a GGUF array should be of the same type"
-            self.fout.write(struct.pack("<I", list(ltype)[0]))
-            self.fout.write(struct.pack("<I", len(val)))
+            self.kv_data += struct.pack("<I", list(ltype)[0])
+            self.kv_data += struct.pack("<I", len(val))
             for item in val:
-                self.write_val(item, write_vtype=False)
+                self.add_val(item, add_vtype=False)
         else:
             raise ValueError("Invalid GGUF metadata value type")
 
@@ -160,22 +175,23 @@ class GGUFWriter:
     def ggml_pad(x: int, n: int) -> int:
         return ((x + n - 1) // n) * n
 
-    def write_tensor_info(self, name: str, tensor: np.ndarray):
-        self.write_key(name)
+    def add_tensor_info(self, name: str, tensor: np.ndarray):
+        encoded_name = name.encode("utf8")
+        self.ti_data += struct.pack("<I", len(encoded_name))
+        self.ti_data += encoded_name
         n_dims = len(tensor.shape)
-        self.fout.write(struct.pack("<i", n_dims))
+        self.ti_data += struct.pack("<I", n_dims)
         for i in range(n_dims):
-            self.fout.write(struct.pack("<i", tensor.shape[n_dims - 1 - i]))
+            self.ti_data += struct.pack("<I", tensor.shape[n_dims - 1 - i])
 
         assert tensor.dtype in (np.float32, np.float16), "Only F32 and F16 tensors are supported for now"
         dtype = GGMLQuantizationType.F32 if tensor.dtype == np.float32 else GGMLQuantizationType.F16
-        self.fout.write(struct.pack("<i", dtype))
-        self.fout.write(struct.pack("<Q", self.offset_tensor))
+        self.ti_data += struct.pack("<I", dtype)
+        self.ti_data += struct.pack("<Q", self.offset_tensor)
         self.offset_tensor += GGUFWriter.ggml_pad(tensor.nbytes, constants.GGUF_DEFAULT_ALIGNMENT)
+        self.ti_data_count += 1
 
-        self.flush()
-
-    def write_tensor(self, tensor: np.ndarray):
+    def write_tensor_to_file(self, tensor: np.ndarray):
         pad = GGUFWriter.ggml_pad(self.fout.tell(), constants.GGUF_DEFAULT_ALIGNMENT) - self.fout.tell()
         if pad != 0:
             self.fout.write(bytes([0] * pad))
@@ -191,121 +207,139 @@ class GGUFWriter:
     def close(self):
         self.fout.close()
 
-    def write_architecture(self, architecture: str):
-        self.write_string(constants.KEY_GENERAL_ARCHITECTURE,
+    def add_architecture(self, architecture: str):
+        self.add_string(constants.KEY_GENERAL_ARCHITECTURE,
                           architecture)
 
-    def write_author(self, author: str):
-        self.write_string(constants.KEY_GENERAL_AUTHOR, author)
+    def add_author(self, author: str):
+        self.add_string(constants.KEY_GENERAL_AUTHOR, author)
 
-    def write_url(self, url: str):
-        self.write_string(constants.KEY_GENERAL_URL, url)
+    def add_url(self, url: str):
+        self.add_string(constants.KEY_GENERAL_URL, url)
 
-    def write_description(self, description: str):
-        self.write_string(constants.KEY_GENERAL_DESCRIPTION, description)
+    def add_description(self, description: str):
+        self.add_string(constants.KEY_GENERAL_DESCRIPTION, description)
 
-    def write_file_type(self, file_type: str):
-        self.write_string(constants.KEY_GENERAL_FILE_TYPE, file_type)
+    def add_file_type(self, file_type: str):
+        self.add_string(constants.KEY_GENERAL_FILE_TYPE, file_type)
 
-    def write_source_url(self, url: str):
-        self.write_string(constants.KEY_GENERAL_SOURCE_URL, url)
+    def add_source_url(self, url: str):
+        self.add_string(constants.KEY_GENERAL_SOURCE_URL, url)
 
-    def write_source_hf_repo(self, repo: str):
-        self.write_string(constants.KEY_GENERAL_SOURCE_HF_REPO, repo)
+    def add_source_hf_repo(self, repo: str):
+        self.add_string(constants.KEY_GENERAL_SOURCE_HF_REPO, repo)
 
-    def write_name(self, name: str):
-        self.write_string(constants.KEY_GENERAL_NAME, name)
+    def add_name(self, name: str):
+        self.add_string(constants.KEY_GENERAL_NAME, name)
 
-    def write_quantization_version(self, quantization_version: GGMLQuantizationType):
-        self.write_uint32(
+    def add_quantization_version(self, quantization_version: GGMLQuantizationType):
+        self.add_uint32(
             constants.KEY_GENERAL_QUANTIZATION_VERSION, quantization_version)
 
-    def write_custom_alignment(self, alignment: int):
-        self.write_uint32(constants.KEY_GENERAL_ALIGNMENT, alignment)
+    def add_custom_alignment(self, alignment: int):
+        self.add_uint32(constants.KEY_GENERAL_ALIGNMENT, alignment)
 
-    def write_context_length(self, llm: str, length: int):
-        self.write_uint32(
+    def add_context_length(self, llm: str, length: int):
+        self.add_uint32(
             constants.KEY_LLM_CONTEXT_LENGTH.format(llm=llm), length)
 
-    def write_embedding_length(self, llm: str, length: int):
-        self.write_uint32(
+    def add_embedding_length(self, llm: str, length: int):
+        self.add_uint32(
             constants.KEY_LLM_EMBEDDING_LENGTH.format(llm=llm), length)
 
-    def write_layer_count(self, llm: str, length: int):
-        self.write_uint32(
+    def add_layer_count(self, llm: str, length: int):
+        self.add_uint32(
             constants.KEY_LLM_LAYER_COUNT.format(llm=llm), length)
 
-    def write_feed_forward_length(self, llm: str, length: int):
-        self.write_uint32(
+    def add_feed_forward_length(self, llm: str, length: int):
+        self.add_uint32(
             constants.KEY_LLM_FEED_FORWARD_LENGTH.format(llm=llm), length)
 
-    def write_parallel_residual(self, llm: str, use: bool):
-        self.write_bool(
+    def add_parallel_residual(self, llm: str, use: bool):
+        self.add_bool(
             constants.KEY_LLM_USE_PARALLEL_RESIDUAL.format(llm=llm), use)
 
-    def write_tensor_data_layout(self, llm: str, layout: str):
-        self.write_string(
+    def add_tensor_data_layout(self, llm: str, layout: str):
+        self.add_string(
             constants.KEY_LLM_TENSOR_DATA_LAYOUT.format(llm=llm), layout)
 
-    def write_head_count(self, llm: str, count: int):
-        self.write_uint32(
+    def add_head_count(self, llm: str, count: int):
+        self.add_uint32(
             constants.KEY_ATTENTION_HEAD_COUNT.format(llm=llm), count)
 
-    def write_head_count_kv(self, llm: str, count: int):
-        self.write_uint32(
+    def add_head_count_kv(self, llm: str, count: int):
+        self.add_uint32(
             constants.KEY_ATTENTION_HEAD_COUNT_KV.format(llm=llm), count)
 
-    def write_max_alibi_bias(self, llm: str, bias: float):
-        self.write_float32(
+    def add_max_alibi_bias(self, llm: str, bias: float):
+        self.add_float32(
             constants.KEY_ATTENTION_MAX_ALIBI_BIAS.format(llm=llm), bias)
 
-    def write_clamp_kqv(self, llm: str, value: float):
-        self.write_float32(
+    def add_clamp_kqv(self, llm: str, value: float):
+        self.add_float32(
             constants.KEY_ATTENTION_CLAMP_KQV.format(llm=llm), value)
 
-    def write_layer_norm_eps(self, llm: str, value: float):
-        self.write_float32(
+    def add_layer_norm_eps(self, llm: str, value: float):
+        self.add_float32(
             constants.KEY_ATTENTION_LAYERNORM_EPS.format(llm=llm), value)
 
-    def write_layer_norm_rms_eps(self, llm: str, value: float):
-        self.write_float32(
+    def add_layer_norm_rms_eps(self, llm: str, value: float):
+        self.add_float32(
             constants.KEY_ATTENTION_LAYERNORM_RMS_EPS.format(llm=llm), value)
 
-    def write_rope_dimension_count(self, llm: str, count: int):
-        self.write_uint32(
+    def add_rope_dimension_count(self, llm: str, count: int):
+        self.add_uint32(
             constants.KEY_ROPE_DIMENSION_COUNT.format(llm=llm), count)
 
-    def write_rope_scale(self, llm: str, value:  float):
-        self.write_float32(constants.KEY_ROPE_SCALE.format(llm=llm), value)
+    def add_rope_scale(self, llm: str, value:  float):
+        self.add_float32(constants.KEY_ROPE_SCALE.format(llm=llm), value)
 
-    def write_tokenizer_model(self, model: str):
-        self.write_string(constants.KEY_TOKENIZER_MODEL, model)
+    def add_tokenizer_model(self, model: str):
+        self.add_string(constants.KEY_TOKENIZER_MODEL, model)
 
-    def write_token_list(self, tokens: List):
-        self.write_array(constants.KEY_TOKENIZER_LIST, tokens)
+    def add_token_list(self, tokens: List):
+        self.add_array(constants.KEY_TOKENIZER_LIST, tokens)
 
-    def write_token_merges(self, merges: List):
-        self.write_array(constants.KEY_TOKENIZER_MERGES, merges)
+    def add_token_merges(self, merges: List):
+        self.add_array(constants.KEY_TOKENIZER_MERGES, merges)
 
-    def write_token_scores(self, scores: List[float]):
-        self.write_array(constants.KEY_TOKENIZER_SCORES, scores)
+    def add_token_scores(self, scores: List[float]):
+        self.add_array(constants.KEY_TOKENIZER_SCORES, scores)
+    
+    def add_bos_token_id(self, id: int):
+        self.add_uint32(constants.KEY_TOKENIZER_BOS_ID, id)
+
+    def add_eos_token_id(self, id: int):
+        self.add_uint32(constants.KEY_TOKENIZER_EOS_ID, id)
+
+    def add_unk_token_id(self, id: int):
+        self.add_uint32(constants.KEY_TOKENIZER_UNK_ID, id)
+
+    def add_sep_token_id(self, id: int):
+        self.add_uint32(constants.KEY_TOKENIZER_SEP_ID, id)
+
+    def add_pad_token_id(self, id: int):
+        self.add_uint32(constants.KEY_TOKENIZER_PAD_ID, id)
 
 
 # Example usage:
 if __name__ == "__main__":
     # Example usage with a file
     gguf_writer = GGUFWriter.open("example.gguf")
-    gguf_writer.write_header(2, 4)
 
-    gguf_writer.write_architecture("llama")
-    gguf_writer.write_uint32("answer", 42)  # Write a 32-bit integer
-    gguf_writer.write_float32("answer_in_float", 42.0)  # Write a 32-bit float
-    gguf_writer.write_custom_alignment(64)
+    gguf_writer.add_architecture("llama")
+    gguf_writer.add_uint32("answer", 42)  # Write a 32-bit integer
+    gguf_writer.add_float32("answer_in_float", 42.0)  # Write a 32-bit float
+    gguf_writer.add_custom_alignment(64)
     tensor1 = np.ones((32,), dtype=np.float32) * 100.0
     tensor2 = np.ones((32,), dtype=np.float32) * 101.0
-    gguf_writer.write_tensor_info("tensor0", tensor1)
-    gguf_writer.write_tensor_info("tensor1", tensor2)
-    gguf_writer.write_tensor(tensor1)
-    gguf_writer.write_tensor(tensor2)
+    gguf_writer.add_tensor_info("tensor0", tensor1)
+    gguf_writer.add_tensor_info("tensor1", tensor2)
+
+    gguf_writer.write_header_to_file()
+    gguf_writer.write_kv_data_to_file()
+    gguf_writer.write_ti_data_to_file()
+    gguf_writer.write_tensor_to_file(tensor1)
+    gguf_writer.write_tensor_to_file(tensor2)
 
     gguf_writer.close()