diff --git a/ggml.c b/ggml.c
index cdba137da..8e9cd42d7 100644
--- a/ggml.c
+++ b/ggml.c
@@ -18613,8 +18613,6 @@ struct gguf_header {
     uint32_t version;
     uint32_t n_tensors;
     uint32_t n_kv;
-
-    struct gguf_kv * kv;
 };
 
 struct gguf_tensor_info {
@@ -18630,7 +18628,9 @@ struct gguf_tensor_info {
 };
 
 struct gguf_context {
-    struct gguf_header        header;
+    struct gguf_header header;
+
+    struct gguf_kv          * kv;
     struct gguf_tensor_info * infos;
 
     size_t alignment;
@@ -18660,6 +18660,26 @@ static bool gguf_fread_str(struct gguf_str * p, FILE * file, size_t * offset) {
     return ok;
 }
 
+struct gguf_context * gguf_init_empty(void) {
+    struct gguf_context * ctx = GGML_ALIGNED_MALLOC(sizeof(struct gguf_context));
+
+    ctx->header.magic     = GGUF_MAGIC;
+    ctx->header.version   = GGUF_VERSION;
+    ctx->header.n_tensors = 0;
+    ctx->header.n_kv      = 0;
+
+    ctx->kv    = NULL;
+    ctx->infos = NULL;
+
+    ctx->alignment = GGUF_DEFAULT_ALIGNMENT;
+    ctx->offset    = 0;
+    ctx->size_data = 0;
+
+    ctx->data = NULL;
+
+    return ctx;
+}
+
 struct gguf_context * gguf_init_from_file(const char * fname, struct gguf_init_params params) {
     FILE * file = fopen(fname, "rb");
     if (!file) {
@@ -18689,8 +18709,8 @@ struct gguf_context * gguf_init_from_file(const char * fname, struct gguf_init_p
     // read the header
     {
         ctx->header.magic = magic;
-        ctx->header.kv    = NULL;
 
+        ctx->kv    = NULL;
         ctx->infos = NULL;
         ctx->data  = NULL;
 
@@ -18708,10 +18728,10 @@ struct gguf_context * gguf_init_from_file(const char * fname, struct gguf_init_p
 
     // read the kv pairs
     {
-        ctx->header.kv = GGML_ALIGNED_MALLOC(ctx->header.n_kv * sizeof(struct gguf_kv));
+        ctx->kv = GGML_ALIGNED_MALLOC(ctx->header.n_kv * sizeof(struct gguf_kv));
 
         for (uint32_t i = 0; i < ctx->header.n_kv; ++i) {
-            struct gguf_kv * kv = &ctx->header.kv[i];
+            struct gguf_kv * kv = &ctx->kv[i];
 
             //fprintf(stderr, "%s: reading kv %d\n", __func__, i);
 
@@ -18757,7 +18777,7 @@ struct gguf_context * gguf_init_from_file(const char * fname, struct gguf_init_p
                                     }
                                 } break;
                             case GGUF_TYPE_ARRAY:
-                            case GGUF_TYPE_COUNT: GGML_ASSERT(false && "invalid type");
+                            case GGUF_TYPE_COUNT: GGML_ASSERT(false && "invalid type"); break;
                         };
                     } break;
                 case GGUF_TYPE_COUNT: GGML_ASSERT(false && "invalid type");
@@ -18827,7 +18847,6 @@ struct gguf_context * gguf_init_from_file(const char * fname, struct gguf_init_p
 
     // compute the total size of the data section, taking into account the alignment
     {
-
         ctx->size_data = 0;
         for (uint32_t i = 0; i < ctx->header.n_tensors; ++i) {
             struct gguf_tensor_info * info = &ctx->infos[i];
@@ -18944,10 +18963,10 @@ void gguf_free(struct gguf_context * ctx) {
         return;
     }
 
-    if (ctx->header.kv) {
+    if (ctx->kv) {
         // free string memory - not great..
         for (uint32_t i = 0; i < ctx->header.n_kv; ++i) {
-            struct gguf_kv * kv = &ctx->header.kv[i];
+            struct gguf_kv * kv = &ctx->kv[i];
 
             if (kv->key.data) {
                 free(kv->key.data);
@@ -18974,7 +18993,7 @@ void gguf_free(struct gguf_context * ctx) {
             }
         }
 
-        GGML_ALIGNED_FREE(ctx->header.kv);
+        GGML_ALIGNED_FREE(ctx->kv);
     }
 
     if (ctx->infos) {
@@ -19014,8 +19033,9 @@ int gguf_get_n_kv(struct gguf_context * ctx) {
 
 int gguf_find_key(struct gguf_context * ctx, const char * key) {
     // return -1 if key not found
+    int keyfound = -1;
+
     const int n_kv = gguf_get_n_kv(ctx);
-    int keyfound   = -1;
 
     for (int i = 0; i < n_kv; ++i) {
         if (strcmp(key, gguf_get_key(ctx, i)) == 0) {
@@ -19028,69 +19048,69 @@ int gguf_find_key(struct gguf_context * ctx, const char * key) {
 }
 
 const char * gguf_get_key(struct gguf_context * ctx, int i) {
-    return ctx->header.kv[i].key.data;
+    return ctx->kv[i].key.data;
 }
 
 enum gguf_type gguf_get_kv_type(struct gguf_context * ctx, int i) {
-    return ctx->header.kv[i].type;
+    return ctx->kv[i].type;
 }
 
 enum gguf_type gguf_get_arr_type(struct gguf_context * ctx, int i) {
-    return ctx->header.kv[i].value.arr.type;
+    return ctx->kv[i].value.arr.type;
 }
 
 int32_t gguf_get_arr_i32(struct gguf_context * ctx, int key_id, int i) {
-    return ((int32_t *) ctx->header.kv[key_id].value.arr.data)[i];
+    return ((int32_t *) ctx->kv[key_id].value.arr.data)[i];
 }
 
 float gguf_get_arr_f32(struct gguf_context * ctx, int key_id, int i) {
-    return ((float *) ctx->header.kv[key_id].value.arr.data)[i];
+    return ((float *) ctx->kv[key_id].value.arr.data)[i];
 }
 
 const char * gguf_get_arr_str(struct gguf_context * ctx, int key_id, int i) {
-    struct gguf_kv * kv = &ctx->header.kv[key_id];
+    struct gguf_kv * kv = &ctx->kv[key_id];
     struct gguf_str * str = &((struct gguf_str *) kv->value.arr.data)[i];
     return str->data;
 }
 
 int gguf_get_arr_n(struct gguf_context * ctx, int i) {
-    return ctx->header.kv[i].value.arr.n;
+    return ctx->kv[i].value.arr.n;
 }
 
 uint8_t gguf_get_val_u8(struct gguf_context * ctx, int i) {
-    return ctx->header.kv[i].value.uint8;
+    return ctx->kv[i].value.uint8;
 }
 
 int8_t gguf_get_val_i8(struct gguf_context * ctx, int i) {
-    return ctx->header.kv[i].value.int8;
+    return ctx->kv[i].value.int8;
 }
 
 uint16_t gguf_get_val_u16(struct gguf_context * ctx, int i) {
-    return ctx->header.kv[i].value.uint16;
+    return ctx->kv[i].value.uint16;
 }
 
 int16_t gguf_get_val_i16(struct gguf_context * ctx, int i) {
-    return ctx->header.kv[i].value.int16;
+    return ctx->kv[i].value.int16;
 }
 
 uint32_t gguf_get_val_u32(struct gguf_context * ctx, int i) {
-    return ctx->header.kv[i].value.uint32;
+    return ctx->kv[i].value.uint32;
 }
 
 int32_t gguf_get_val_i32(struct gguf_context * ctx, int i) {
-    return ctx->header.kv[i].value.int32;
+    return ctx->kv[i].value.int32;
 }
 
 float gguf_get_val_f32(struct gguf_context * ctx, int i) {
-    return ctx->header.kv[i].value.float32;
+    return ctx->kv[i].value.float32;
 }
 
 bool gguf_get_val_bool(struct gguf_context * ctx, int i) {
-    return ctx->header.kv[i].value.bool_;
+    return ctx->kv[i].value.bool_;
 }
 
 const char * gguf_get_val_str (struct gguf_context * ctx, int i) {
-    return ctx->header.kv[i].value.str.data;
+    return ctx->kv[i].value.str.data;
 }
 
 int gguf_get_n_tensors(struct gguf_context * ctx) {
@@ -19105,6 +19125,164 @@ char * gguf_get_tensor_name(struct gguf_context * ctx, int i) {
     return ctx->infos[i].name.data;
 }
 
+// returns the index
+static int gguf_get_or_add_key(struct gguf_context * ctx, const char * key) {
+    const int idx = gguf_find_key(ctx, key);
+    if (idx >= 0) {
+        return idx;
+    }
+
+    const int n_kv = gguf_get_n_kv(ctx);
+
+    ctx->kv = realloc(ctx->kv, (n_kv + 1) * sizeof(struct gguf_kv));
+    ctx->kv[n_kv].key.n    = strlen(key) + 1;
+    ctx->kv[n_kv].key.data = strdup(key);
+    ctx->header.n_kv++;
+
+    return n_kv;
+}
+
+void gguf_set_val_u8(struct gguf_context * ctx, const char * key, uint8_t val) {
+    const int idx = gguf_get_or_add_key(ctx, key);
+
+    ctx->kv[idx].type        = GGUF_TYPE_UINT8;
+    ctx->kv[idx].value.uint8 = val;
+}
+
+void gguf_set_val_i8(struct gguf_context * ctx, const char * key, int8_t val) {
+    const int idx = gguf_get_or_add_key(ctx, key);
+
+    ctx->kv[idx].type       = GGUF_TYPE_INT8;
+    ctx->kv[idx].value.int8 = val;
+}
+
+void gguf_set_val_u16(struct gguf_context * ctx, const char * key, uint16_t val) {
+    const int idx = gguf_get_or_add_key(ctx, key);
+
+    ctx->kv[idx].type         = GGUF_TYPE_UINT16;
+    ctx->kv[idx].value.uint16 = val;
+}
+
+void gguf_set_val_i16(struct gguf_context * ctx, const char * key, int16_t val) {
+    const int idx = gguf_get_or_add_key(ctx, key);
+
+    ctx->kv[idx].type        = GGUF_TYPE_INT16;
+    ctx->kv[idx].value.int16 = val;
+}
+
+void gguf_set_val_u32(struct gguf_context * ctx, const char * key, uint32_t val) {
+    const int idx = gguf_get_or_add_key(ctx, key);
+
+    ctx->kv[idx].type         = GGUF_TYPE_UINT32;
+    ctx->kv[idx].value.uint32 = val;
+}
+
+void gguf_set_val_i32(struct gguf_context * ctx, const char * key, int32_t val) {
+    const int idx = gguf_get_or_add_key(ctx, key);
+
+    ctx->kv[idx].type        = GGUF_TYPE_INT32;
+    ctx->kv[idx].value.int32 = val;
+}
+
+void gguf_set_val_f32(struct gguf_context * ctx, const char * key, float val) {
+    const int idx = gguf_get_or_add_key(ctx, key);
+
+    ctx->kv[idx].type          = GGUF_TYPE_FLOAT32;
+    ctx->kv[idx].value.float32 = val;
+}
+
+void gguf_set_val_bool(struct gguf_context * ctx, const char * key, bool val) {
+    const int idx = gguf_get_or_add_key(ctx, key);
+
+    ctx->kv[idx].type        = GGUF_TYPE_BOOL;
+    ctx->kv[idx].value.bool_ = val;
+}
+
+void gguf_set_val_str(struct gguf_context * ctx, const char * key, const char * val) {
+    const int idx = gguf_get_or_add_key(ctx, key);
+
+    ctx->kv[idx].type           = GGUF_TYPE_STRING;
+    ctx->kv[idx].value.str.n    = strlen(val) + 1;
+    ctx->kv[idx].value.str.data = strdup(val);
+}
+
+void gguf_set_arr_data(struct gguf_context * ctx, const char * key, enum gguf_type type, const void * data, int n) {
+    const int idx = gguf_get_or_add_key(ctx, key);
+
+    ctx->kv[idx].type           = GGUF_TYPE_ARRAY;
+    ctx->kv[idx].value.arr.type = type;
+    ctx->kv[idx].value.arr.n    = n;
+    ctx->kv[idx].value.arr.data = malloc(n*GGUF_TYPE_SIZE[type]);
+    memcpy(ctx->kv[idx].value.arr.data, data, n*GGUF_TYPE_SIZE[type]);
+}
+
+void gguf_set_arr_str(struct gguf_context * ctx, const char * key, const char ** data, int n) {
+    const int idx = gguf_get_or_add_key(ctx, key);
+
+    ctx->kv[idx].type           = GGUF_TYPE_ARRAY;
+    ctx->kv[idx].value.arr.type = GGUF_TYPE_STRING;
+    ctx->kv[idx].value.arr.n    = n;
+    ctx->kv[idx].value.arr.data = malloc(n*sizeof(struct gguf_str));
+    for (int i = 0; i < n; i++) {
+        struct gguf_str * str = &((struct gguf_str *)ctx->kv[idx].value.arr.data)[i];
+        str->n    = strlen(data[i]) + 1;
+        str->data = strdup(data[i]);
+    }
+}
+
+// set or add KV pairs from another context
+void gguf_set_kv(struct gguf_context * ctx, struct gguf_context * src) {
+    for (uint32_t i = 0; i < src->header.n_kv; i++) {
+        switch (src->kv[i].type) {
+            case GGUF_TYPE_UINT8:   gguf_set_val_u8  (ctx, src->kv[i].key.data, src->kv[i].value.uint8);    break;
+            case GGUF_TYPE_INT8:    gguf_set_val_i8  (ctx, src->kv[i].key.data, src->kv[i].value.int8);     break;
+            case GGUF_TYPE_UINT16:  gguf_set_val_u16 (ctx, src->kv[i].key.data, src->kv[i].value.uint16);   break;
+            case GGUF_TYPE_INT16:   gguf_set_val_i16 (ctx, src->kv[i].key.data, src->kv[i].value.int16);    break;
+            case GGUF_TYPE_UINT32:  gguf_set_val_u32 (ctx, src->kv[i].key.data, src->kv[i].value.uint32);   break;
+            case GGUF_TYPE_INT32:   gguf_set_val_i32 (ctx, src->kv[i].key.data, src->kv[i].value.int32);    break;
+            case GGUF_TYPE_FLOAT32: gguf_set_val_f32 (ctx, src->kv[i].key.data, src->kv[i].value.float32);  break;
+            case GGUF_TYPE_BOOL:    gguf_set_val_bool(ctx, src->kv[i].key.data, src->kv[i].value.bool_);    break;
+            case GGUF_TYPE_STRING:  gguf_set_val_str (ctx, src->kv[i].key.data, src->kv[i].value.str.data); break;
+            case GGUF_TYPE_ARRAY:
+                {
+                    if (src->kv[i].value.arr.type == GGUF_TYPE_STRING) {
+                        const char ** data = malloc(src->kv[i].value.arr.n*sizeof(char *));
+                        for (uint32_t j = 0; j < src->kv[i].value.arr.n; j++) {
+                            data[j] = ((struct gguf_str *)src->kv[i].value.arr.data)[j].data;
+                        }
+                        gguf_set_arr_str(ctx, src->kv[i].key.data, data, src->kv[i].value.arr.n);
+                        free(data);
+                    } if (src->kv[i].value.arr.type == GGUF_TYPE_ARRAY) {
+                        GGML_ASSERT(false && "nested arrays not supported");
+                    } else {
+                        gguf_set_arr_data(ctx, src->kv[i].key.data, src->kv[i].value.arr.type, src->kv[i].value.arr.data, src->kv[i].value.arr.n);
+                    }
+                } break;
+            case GGUF_TYPE_COUNT:  GGML_ASSERT(false && "invalid type"); break;
+        }
+    }
+}
+
+void gguf_add_tensor(struct gguf_context * ctx, const struct ggml_tensor * tensor) {
+    const int idx = ctx->header.n_tensors;
+    ctx->infos = realloc(ctx->infos, (idx + 1)*sizeof(struct gguf_tensor_info));
+
+    ctx->infos[idx].name.n    = strlen(tensor->name) + 1;
+    ctx->infos[idx].name.data = strdup(tensor->name);
+
+    ctx->infos[idx].n_dims = tensor->n_dims;
+    for (int i = 0; i < tensor->n_dims; i++) {
+        ctx->infos[idx].ne[i] = tensor->ne[i];
+    }
+    //ctx->infos[idx].n_elms = tensor->n_elms;
+
+    ctx->infos[idx].type = tensor->type;
+
+    ctx->infos[idx].offset = -1; // set later;
+
+    ctx->header.n_tensors++;
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 
 int ggml_cpu_has_avx(void) {
diff --git a/ggml.h b/ggml.h
index 79bda4538..96c3c707e 100644
--- a/ggml.h
+++ b/ggml.h
@@ -1735,6 +1735,7 @@ extern "C" {
         struct ggml_context ** ctx;
     };
 
+    GGML_API struct gguf_context * gguf_init_empty(void);
     GGML_API struct gguf_context * gguf_init_from_file(const char * fname, struct gguf_init_params params);
     //GGML_API struct gguf_context * gguf_init_from_buffer(..);
     GGML_API void                  gguf_free(struct gguf_context * ctx);
@@ -1751,9 +1752,8 @@ extern "C" {
     GGML_API enum gguf_type gguf_get_kv_type (struct gguf_context * ctx, int i);
     GGML_API enum gguf_type gguf_get_arr_type(struct gguf_context * ctx, int i);
 
-    GGML_API float        gguf_get_arr_f32(struct gguf_context * ctx, int key_id, int i);
-    GGML_API int32_t      gguf_get_arr_i32(struct gguf_context * ctx, int key_id, int i);
-    GGML_API const char * gguf_get_arr_str(struct gguf_context * ctx, int key_id, int i);
+    GGML_API int32_t      gguf_get_arr_i32(struct gguf_context * ctx, int key_id, int i); // TODO: remove
+    GGML_API float        gguf_get_arr_f32(struct gguf_context * ctx, int key_id, int i); // TODO: remove
 
     GGML_API uint8_t      gguf_get_val_u8  (struct gguf_context * ctx, int i);
     GGML_API int8_t       gguf_get_val_i8  (struct gguf_context * ctx, int i);
@@ -1766,11 +1766,30 @@ extern "C" {
     GGML_API const char * gguf_get_val_str (struct gguf_context * ctx, int i);
     GGML_API int          gguf_get_arr_n   (struct gguf_context * ctx, int i);
     GGML_API void         gguf_get_arr_data(struct gguf_context * ctx, int i, void * data);
+    GGML_API const char * gguf_get_arr_str (struct gguf_context * ctx, int key_id, int i);
 
     GGML_API int    gguf_get_n_tensors    (struct gguf_context * ctx);
     GGML_API size_t gguf_get_tensor_offset(struct gguf_context * ctx, int i);
     GGML_API char * gguf_get_tensor_name  (struct gguf_context * ctx, int i);
 
+    // overrides existing values or adds a new one
+    GGML_API void gguf_set_val_u8  (struct gguf_context * ctx, const char * key, uint8_t  val);
+    GGML_API void gguf_set_val_i8  (struct gguf_context * ctx, const char * key, int8_t   val);
+    GGML_API void gguf_set_val_u16 (struct gguf_context * ctx, const char * key, uint16_t val);
+    GGML_API void gguf_set_val_i16 (struct gguf_context * ctx, const char * key, int16_t  val);
+    GGML_API void gguf_set_val_u32 (struct gguf_context * ctx, const char * key, uint32_t val);
+    GGML_API void gguf_set_val_i32 (struct gguf_context * ctx, const char * key, int32_t  val);
+    GGML_API void gguf_set_val_f32 (struct gguf_context * ctx, const char * key, float    val);
+    GGML_API void gguf_set_val_bool(struct gguf_context * ctx, const char * key, bool     val);
+    GGML_API void gguf_set_val_str (struct gguf_context * ctx, const char * key, const char * val);
+    GGML_API void gguf_set_arr_data(struct gguf_context * ctx, const char * key, enum gguf_type type, const void * data, int n);
+    GGML_API void gguf_set_arr_str (struct gguf_context * ctx, const char * key, const char ** data, int n);
+
+    // set or add KV pairs from another context
+    GGML_API void gguf_set_kv(struct gguf_context * ctx, struct gguf_context * src);
+
+    GGML_API void gguf_add_tensor(struct gguf_context * ctx, const struct ggml_tensor * tensor);
+
     //
     // system info
     //
diff --git a/gguf-llama.cpp b/gguf-llama.cpp
index b4cb86478..684b30936 100644
--- a/gguf-llama.cpp
+++ b/gguf-llama.cpp
@@ -710,17 +710,18 @@ struct gguf_file_saver {
     // but better to have it as uint32).
     // we need to calculate the delta in number of bytes written with a counter as a struct member.
 
-    gguf_file file;
     gguf_context * ctx; // loaded gguf context (used to re-write the KV section (good enough for now))
-    size_t info_offset;
-    size_t tensor_offset = 0;
 
-    gguf_file_saver(const char * fname, gguf_context * ctx)
-        : file(fname, "wb"), ctx(ctx) {
-            fprintf(stderr, "llama.cpp: saving model to %s\n", fname);
-            write_header();
-            write_kv();
-        }
+    gguf_file file;
+    size_t info_offset;
+    size_t tensor_offset;
+
+    gguf_file_saver(const char * fname, gguf_context * ctx) : ctx(ctx), file(fname, "wb") {
+        LLAMA_LOG_INFO("%s: saving model to %s\n", __func__, fname);
+
+        write_header();
+        write_kv();
+    }
 
     void write_header() {
         file.write_i32(GGUF_MAGIC);
@@ -729,15 +730,15 @@ struct gguf_file_saver {
         file.write_i32(gguf_get_n_kv     (ctx));
     }
 
-    void write_kv_arr_str(const std::string & key, enum gguf_type type, int i, int n_arr) {
-        std::vector<std::string> data(n_arr);
+    void write_kv_arr_i32(const std::string & key, enum gguf_type type, int i, int n_arr) {
+        std::vector<int32_t> data(n_arr);
 
         for (int j = 0; j < n_arr; ++j) {
-            std::string val = gguf_get_arr_str(ctx, i, j);
+            int32_t val = gguf_get_arr_i32(ctx, i, j);
             data[j] = val;
         }
 
-        file.write_arr(key, type, data);
+        file.write_arr<int32_t>(key, type, data);
     }
 
     void write_kv_arr_f32(const std::string & key, enum gguf_type type, int i, int n_arr) {
@@ -751,15 +752,15 @@ struct gguf_file_saver {
         file.write_arr<float>(key, type, data);
     }
 
-    void write_kv_arr_i32(const std::string & key, enum gguf_type type, int i, int n_arr) {
-        std::vector<int32_t> data(n_arr);
+    void write_kv_arr_str(const std::string & key, enum gguf_type type, int i, int n_arr) {
+        std::vector<std::string> data(n_arr);
 
         for (int j = 0; j < n_arr; ++j) {
-            int32_t val = gguf_get_arr_i32(ctx, i, j);
+            std::string val = gguf_get_arr_str(ctx, i, j);
             data[j] = val;
         }
 
-        file.write_arr<int32_t>(key, type, data);
+        file.write_arr(key, type, data);
     }
 
     // re-write the key-value section from the loaded file
@@ -807,16 +808,15 @@ struct gguf_file_saver {
 
         GGML_ASSERT(gguf_get_data_offset(ctx) >= info_offset);
 
-        size_t count = gguf_get_data_offset(ctx) - info_offset;
+        const size_t count = gguf_get_data_offset(ctx) - info_offset;
+
         file.write_zeros(count);
         file.seek(info_offset, SEEK_SET);
-        GGML_ASSERT(info_offset == file.tell());
     }
 
     size_t write_tensor_info(gguf_load_tensor & tensor, enum ggml_type type) {
         size_t total_written = 0;
         file.seek(info_offset, SEEK_SET);
-        GGML_ASSERT(info_offset == file.tell());
         total_written += file.write_str(tensor.name);
 
         int32_t n_dims = tensor.ne.size();