diff --git a/common/include/entity/registry.h b/common/include/entity/registry.h
index 55972bb..6a885b4 100644
--- a/common/include/entity/registry.h
+++ b/common/include/entity/registry.h
@@ -3,6 +3,8 @@
 
 #include <stdlib.h>
 
+#include <jansson.h>
+
 #include "error.h"
 
 struct entity_registrant_t {
@@ -27,6 +29,16 @@ struct entity_registry_t {
 enum error_t entity_registry_init(struct entity_registry_t *);
 void entity_registry_free(struct entity_registry_t *);
 
+enum error_t entity_registry_serialise(
+    struct entity_registry_t const *,
+    struct json_t **
+);
+
+enum error_t entity_registry_deserialise(
+    struct entity_registry_t *,
+    struct json_t *
+);
+
 enum error_t entity_registry_append(
     struct entity_registry_t *,
     struct entity_registrant_t const *
diff --git a/common/src/entity/registry.c b/common/src/entity/registry.c
index 9f3733e..fc31e11 100644
--- a/common/src/entity/registry.c
+++ b/common/src/entity/registry.c
@@ -9,6 +9,10 @@
 #define MAX_NAME_LENGTH 32
 
 
+static char const* const ENTITY_REGISTRANT_JSON_FMT = "{ss,si}";
+static char const* const ENTITY_REGISTRY_JSON_FMT = "{so,sI}";
+
+
 enum error_t entity_registrant_init(
     struct entity_registrant_t *self,
     char const *name, char tile
@@ -36,6 +40,40 @@ void entity_registrant_free(struct entity_registrant_t *self) {
 }
 
 
+static enum error_t registrant_serialise(
+    struct entity_registrant_t const *self,
+    struct json_t **json
+) {
+    assert(self != NULL);
+    assert(json != NULL);
+
+    struct json_t *maybe_json = json_pack(ENTITY_REGISTRANT_JSON_FMT,
+        "name", self->name,
+        "tile", self->tile
+    );
+    if (maybe_json == NULL) return ERR_JSON_SERIALISE;
+
+    *json = maybe_json;
+    return ERR_OK;
+}
+
+static enum error_t registrant_deserialise(
+    struct entity_registrant_t *self,
+    struct json_t *json
+) {
+    assert(self != NULL);
+    assert(json != NULL);
+
+    int err = json_unpack(json, ENTITY_REGISTRANT_JSON_FMT,
+        "name", &self->name,
+        "tile", &self->tile
+    );
+    if (err < 0) return ERR_JSON_DESERIALISE;
+
+    return ERR_OK;
+}
+
+
 enum error_t entity_registry_init(struct entity_registry_t *self) {
     assert(self != NULL);
 
@@ -62,6 +100,79 @@ void entity_registry_free(struct entity_registry_t *self) {
 }
 
 
+enum error_t entity_registry_serialise(
+    struct entity_registry_t const *self,
+    struct json_t **json
+) {
+    assert(self != NULL);
+    assert(json != NULL);
+
+    enum error_t err = ERR_OK;
+
+    struct json_t *entities_json = json_array();
+    for (size_t i = 0; i < self->size; i++) {
+        struct json_t *maybe_entity_json;
+        err = registrant_serialise(&self->entities[i], &maybe_entity_json);
+        if (err != ERR_OK) goto error_cleanup_array;
+
+        int json_err = json_array_append_new(entities_json, maybe_entity_json);
+        if (json_err < 0) goto error_cleanup_array;
+    }
+    assert(json_array_size(entities_json) == self->size);
+
+    struct json_t *maybe_json = json_pack(ENTITY_REGISTRY_JSON_FMT,
+        "entities", entities_json,
+        "size", self->size
+    );
+    if (maybe_json == NULL) goto error_cleanup_array;
+
+    *json = maybe_json;
+    return ERR_OK;
+
+error_cleanup_array:
+    json_array_clear(entities_json);
+    return err;
+}
+
+
+enum error_t entity_registry_deserialise(
+    struct entity_registry_t *self,
+    struct json_t *json
+) {
+    assert(self != NULL);
+    assert(json != NULL);
+
+    enum error_t err = ERR_OK;
+
+    struct json_t *entities_json = NULL;
+    int json_err = json_unpack(json, ENTITY_REGISTRY_JSON_FMT,
+        "entities", &entities_json,
+        "size", &self->size
+    );
+    if (json_err < 0) return ERR_JSON_DESERIALISE;
+
+    struct entity_registrant_t *entities = calloc(
+        self->size, sizeof(struct entity_registrant_t)
+    );
+    if (entities == NULL) goto error_cleanup_entities;
+
+    for (size_t i = 0; i < json_array_size(entities_json); i++) {
+        struct json_t *entity_json = json_array_get(entities_json, i);
+        if (entity_json == NULL) goto error_cleanup_entities;
+
+        err = registrant_deserialise(&entities[i], entity_json);
+        if (err != ERR_OK) goto error_cleanup_entities;
+    }
+
+    self->entities = entities;
+    return ERR_OK;
+
+error_cleanup_entities:
+    free(entities);
+    return ERR_JSON_DESERIALISE;
+}
+
+
 enum error_t entity_registry_append(
     struct entity_registry_t *self,
     struct entity_registrant_t const *registrant
diff --git a/common/src/world.c b/common/src/world.c
index 13eeb75..ee702d6 100644
--- a/common/src/world.c
+++ b/common/src/world.c
@@ -5,6 +5,8 @@
 
 #include "world.h"
 
+static char const *const JSON_FMT = "{so, sI, sI}";
+
 enum error_t world_init(struct world_t *self, size_t height, size_t width) {
     assert(self != NULL);
 
@@ -42,11 +44,20 @@ void world_free(struct world_t *self) {
 
 static enum error_t serialise(struct world_t *self, struct json_t **json) {
     assert(self != NULL);
+    assert(json != NULL);
     // TODO: (de)serialise the following:
     // struct entity_t entities[MAX_ENTITIES];
     // struct entity_registry_t registered_entities;
 
-    struct json_t *maybe_json = json_pack("{s:I,s:I}",
+    struct json_t *registered_entities_json;
+    enum error_t err = entity_registry_serialise(
+        &self->registered_entities,
+        &registered_entities_json
+    );
+    if (err != ERR_OK) return err;
+
+    struct json_t *maybe_json = json_pack(JSON_FMT,
+        "registered_entities", registered_entities_json,
         "height", self->height,
         "width", self->width
     );
@@ -57,6 +68,28 @@ static enum error_t serialise(struct world_t *self, struct json_t **json) {
 }
 
 
+static enum error_t deserialise(struct world_t *self, struct json_t *json) {
+    assert(self != NULL);
+    assert(json != NULL);
+
+    struct json_t *registered_entities_json;
+    int json_err = json_unpack(json, JSON_FMT,
+        "registered_entities", &registered_entities_json,
+        "height", &self->height,
+        "width", &self->width
+    );
+    if (json_err < 0) return ERR_JSON_DESERIALISE;
+
+    enum error_t err = entity_registry_deserialise(
+        &self->registered_entities,
+        registered_entities_json
+    );
+    if (err != ERR_OK) return err;
+
+    return ERR_OK;
+}
+
+
 enum error_t world_serialise_str(struct world_t *self, char const **strptr) {
     assert(self != NULL);
     assert(strptr != NULL);
@@ -73,20 +106,6 @@ enum error_t world_serialise_str(struct world_t *self, char const **strptr) {
 }
 
 
-static enum error_t deserialise(struct world_t *self, struct json_t *json) {
-    assert(self != NULL);
-    assert(json != NULL);
-
-    int err = json_unpack(json, "{s:I,s:I}",
-        "height", &self->height,
-        "width", &self->width
-    );
-    if (err < 0) return ERR_JSON_DESERIALISE;
-
-    return ERR_OK;
-}
-
-
 enum error_t world_serialise_buf(struct world_t *self, char *buf, size_t len) {
     assert(self != NULL);
     assert(buf != NULL);
diff --git a/server/src/main.c b/server/src/main.c
index 1acdbdc..66138e5 100644
--- a/server/src/main.c
+++ b/server/src/main.c
@@ -34,14 +34,10 @@ enum error_t game_loop(struct data_t *data) {
     char ibuf[1024] = { 0 };
     read(data->socket_accept, ibuf, 1024);
 
-    struct world_t old_world = data->world;
     err = world_deserialise(&data->world, ibuf);
-    if (err != ERR_OK) return ERR_OK;
+    if (err != ERR_OK) return err;
 
-    printf("SERVER: (%zu %zu) -> (%zu %zu)\n",
-        old_world.height, old_world.width,
-        data->world.height, data->world.width
-    );
+    printf("SERVER: \"%s\" -> \"%s\"\n", obuf, ibuf);
 
     return ERR_OK;
 }