diff --git a/env/mettagrid/c_grid.c b/env/mettagrid/c_grid.c
index 7f6966d..16cdeb0 100644
--- a/env/mettagrid/c_grid.c
+++ b/env/mettagrid/c_grid.c
@@ -1,4 +1,4 @@
-/* Generated by Cython 3.0.8 */
+/* Generated by Cython 3.0.10 */
 
 /* BEGIN: Cython Metadata
 {
@@ -9,12 +9,15 @@
                 "NPY_1_7_API_VERSION"
             ]
         ],
-        "name": "mettagrid.c_grid",
+        "include_dirs": [
+            "/opt/conda/lib/python3.10/site-packages/numpy/core/include"
+        ],
+        "name": "env.mettagrid.c_grid",
         "sources": [
             "env/mettagrid/c_grid.pyx"
         ]
     },
-    "module_name": "mettagrid.c_grid"
+    "module_name": "env.mettagrid.c_grid"
 }
 END: Cython Metadata */
 
@@ -42,10 +45,10 @@ END: Cython Metadata */
 #else
 #define __PYX_EXTRA_ABI_MODULE_NAME ""
 #endif
-#define CYTHON_ABI "3_0_8" __PYX_EXTRA_ABI_MODULE_NAME
+#define CYTHON_ABI "3_0_10" __PYX_EXTRA_ABI_MODULE_NAME
 #define __PYX_ABI_MODULE_NAME "_cython_" CYTHON_ABI
 #define __PYX_TYPE_MODULE_PREFIX __PYX_ABI_MODULE_NAME "."
-#define CYTHON_HEX_VERSION 0x030008F0
+#define CYTHON_HEX_VERSION 0x03000AF0
 #define CYTHON_FUTURE_DIVISION 1
 #include <stddef.h>
 #ifndef offsetof
@@ -137,6 +140,8 @@ END: Cython Metadata */
   #ifndef CYTHON_UPDATE_DESCRIPTOR_DOC
     #define CYTHON_UPDATE_DESCRIPTOR_DOC 0
   #endif
+  #undef CYTHON_USE_FREELISTS
+  #define CYTHON_USE_FREELISTS 0
 #elif defined(PYPY_VERSION)
   #define CYTHON_COMPILING_IN_PYPY 1
   #define CYTHON_COMPILING_IN_CPYTHON 0
@@ -198,6 +203,8 @@ END: Cython Metadata */
   #ifndef CYTHON_UPDATE_DESCRIPTOR_DOC
     #define CYTHON_UPDATE_DESCRIPTOR_DOC 0
   #endif
+  #undef CYTHON_USE_FREELISTS
+  #define CYTHON_USE_FREELISTS 0
 #elif defined(CYTHON_LIMITED_API)
   #ifdef Py_LIMITED_API
     #undef __PYX_LIMITED_VERSION_HEX
@@ -259,6 +266,8 @@ END: Cython Metadata */
   #ifndef CYTHON_UPDATE_DESCRIPTOR_DOC
     #define CYTHON_UPDATE_DESCRIPTOR_DOC 0
   #endif
+  #undef CYTHON_USE_FREELISTS
+  #define CYTHON_USE_FREELISTS 0
 #elif defined(Py_GIL_DISABLED) || defined(Py_NOGIL)
   #define CYTHON_COMPILING_IN_PYPY 0
   #define CYTHON_COMPILING_IN_CPYTHON 0
@@ -268,11 +277,17 @@ END: Cython Metadata */
   #ifndef CYTHON_USE_TYPE_SLOTS
     #define CYTHON_USE_TYPE_SLOTS 1
   #endif
+  #ifndef CYTHON_USE_TYPE_SPECS
+    #define CYTHON_USE_TYPE_SPECS 0
+  #endif
   #undef CYTHON_USE_PYTYPE_LOOKUP
   #define CYTHON_USE_PYTYPE_LOOKUP 0
   #ifndef CYTHON_USE_ASYNC_SLOTS
     #define CYTHON_USE_ASYNC_SLOTS 1
   #endif
+  #ifndef CYTHON_USE_PYLONG_INTERNALS
+    #define CYTHON_USE_PYLONG_INTERNALS 0
+  #endif
   #undef CYTHON_USE_PYLIST_INTERNALS
   #define CYTHON_USE_PYLIST_INTERNALS 0
   #ifndef CYTHON_USE_UNICODE_INTERNALS
@@ -280,8 +295,6 @@ END: Cython Metadata */
   #endif
   #undef CYTHON_USE_UNICODE_WRITER
   #define CYTHON_USE_UNICODE_WRITER 0
-  #undef CYTHON_USE_PYLONG_INTERNALS
-  #define CYTHON_USE_PYLONG_INTERNALS 0
   #ifndef CYTHON_AVOID_BORROWED_REFS
     #define CYTHON_AVOID_BORROWED_REFS 0
   #endif
@@ -293,11 +306,22 @@ END: Cython Metadata */
   #endif
   #undef CYTHON_FAST_THREAD_STATE
   #define CYTHON_FAST_THREAD_STATE 0
+  #undef CYTHON_FAST_GIL
+  #define CYTHON_FAST_GIL 0
+  #ifndef CYTHON_METH_FASTCALL
+    #define CYTHON_METH_FASTCALL 1
+  #endif
   #undef CYTHON_FAST_PYCALL
   #define CYTHON_FAST_PYCALL 0
+  #ifndef CYTHON_PEP487_INIT_SUBCLASS
+    #define CYTHON_PEP487_INIT_SUBCLASS 1
+  #endif
   #ifndef CYTHON_PEP489_MULTI_PHASE_INIT
     #define CYTHON_PEP489_MULTI_PHASE_INIT 1
   #endif
+  #ifndef CYTHON_USE_MODULE_STATE
+    #define CYTHON_USE_MODULE_STATE 0
+  #endif
   #ifndef CYTHON_USE_TP_FINALIZE
     #define CYTHON_USE_TP_FINALIZE 1
   #endif
@@ -305,6 +329,12 @@ END: Cython Metadata */
   #define CYTHON_USE_DICT_VERSIONS 0
   #undef CYTHON_USE_EXC_INFO_STACK
   #define CYTHON_USE_EXC_INFO_STACK 0
+  #ifndef CYTHON_UPDATE_DESCRIPTOR_DOC
+    #define CYTHON_UPDATE_DESCRIPTOR_DOC 1
+  #endif
+  #ifndef CYTHON_USE_FREELISTS
+    #define CYTHON_USE_FREELISTS 0
+  #endif
 #else
   #define CYTHON_COMPILING_IN_PYPY 0
   #define CYTHON_COMPILING_IN_CPYTHON 1
@@ -395,6 +425,9 @@ END: Cython Metadata */
   #ifndef CYTHON_UPDATE_DESCRIPTOR_DOC
     #define CYTHON_UPDATE_DESCRIPTOR_DOC 1
   #endif
+  #ifndef CYTHON_USE_FREELISTS
+    #define CYTHON_USE_FREELISTS 1
+  #endif
 #endif
 #if !defined(CYTHON_FAST_PYCCALL)
 #define CYTHON_FAST_PYCCALL  (CYTHON_FAST_PYCALL && PY_VERSION_HEX >= 0x030600B1)
@@ -738,8 +771,13 @@ END: Cython Metadata */
   typedef PyObject *(*__Pyx_PyCFunctionFastWithKeywords) (PyObject *self, PyObject *const *args,
                                                           Py_ssize_t nargs, PyObject *kwnames);
 #else
-  #define __Pyx_PyCFunctionFast _PyCFunctionFast
-  #define __Pyx_PyCFunctionFastWithKeywords _PyCFunctionFastWithKeywords
+  #if PY_VERSION_HEX >= 0x030d00A4
+  #  define __Pyx_PyCFunctionFast PyCFunctionFast
+  #  define __Pyx_PyCFunctionFastWithKeywords PyCFunctionFastWithKeywords
+  #else
+  #  define __Pyx_PyCFunctionFast _PyCFunctionFast
+  #  define __Pyx_PyCFunctionFastWithKeywords _PyCFunctionFastWithKeywords
+  #endif
 #endif
 #if CYTHON_METH_FASTCALL
   #define __Pyx_METH_FASTCALL METH_FASTCALL
@@ -1091,7 +1129,7 @@ static CYTHON_INLINE PyObject * __Pyx_PyDict_GetItemStrWithError(PyObject *dict,
   #define __Pyx_PyBytes_GET_SIZE(o) PyBytes_Size(o)
   #define __Pyx_PyByteArray_GET_SIZE(o) PyByteArray_Size(o)
 #endif
-#if PY_VERSION_HEX >= 0x030d00A1
+#if __PYX_LIMITED_VERSION_HEX >= 0x030d00A1
   #define __Pyx_PyImport_AddModuleRef(name) PyImport_AddModuleRef(name)
 #else
   static CYTHON_INLINE PyObject *__Pyx_PyImport_AddModuleRef(const char *name) {
@@ -1178,7 +1216,7 @@ static CYTHON_INLINE float __PYX_NAN() {
 #endif
 
 #define __PYX_MARK_ERR_POS(f_index, lineno) \
-    { __pyx_filename = __pyx_f[f_index]; (void)__pyx_filename; __pyx_lineno = lineno; (void)__pyx_lineno; __pyx_clineno = __LINE__; (void)__pyx_clineno; }
+    { __pyx_filename = __pyx_f[f_index]; (void)__pyx_filename; __pyx_lineno = lineno; (void)__pyx_lineno; __pyx_clineno = __LINE__;  (void)__pyx_clineno; }
 #define __PYX_ERR(f_index, lineno, Ln_error) \
     { __PYX_MARK_ERR_POS(f_index, lineno) goto Ln_error; }
 
@@ -1199,8 +1237,8 @@ static CYTHON_INLINE float __PYX_NAN() {
   #endif
 #endif
 
-#define __PYX_HAVE__mettagrid__c_grid
-#define __PYX_HAVE_API__mettagrid__c_grid
+#define __PYX_HAVE__env__mettagrid__c_grid
+#define __PYX_HAVE_API__env__mettagrid__c_grid
 /* Early includes */
 #include "pythread.h"
 #include <string.h>
@@ -1284,24 +1322,7 @@ static CYTHON_INLINE PyObject* __Pyx_PyUnicode_FromString(const char*);
 #define __Pyx_PyByteArray_FromCString(s)   __Pyx_PyByteArray_FromString((const char*)s)
 #define __Pyx_PyStr_FromCString(s)     __Pyx_PyStr_FromString((const char*)s)
 #define __Pyx_PyUnicode_FromCString(s) __Pyx_PyUnicode_FromString((const char*)s)
-#if CYTHON_COMPILING_IN_LIMITED_API
-static CYTHON_INLINE size_t __Pyx_Py_UNICODE_strlen(const wchar_t *u)
-{
-    const wchar_t *u_end = u;
-    while (*u_end++) ;
-    return (size_t)(u_end - u - 1);
-}
-#else
-static CYTHON_INLINE size_t __Pyx_Py_UNICODE_strlen(const Py_UNICODE *u)
-{
-    const Py_UNICODE *u_end = u;
-    while (*u_end++) ;
-    return (size_t)(u_end - u - 1);
-}
-#endif
 #define __Pyx_PyUnicode_FromOrdinal(o)       PyUnicode_FromOrdinal((int)o)
-#define __Pyx_PyUnicode_FromUnicode(u)       PyUnicode_FromUnicode(u, __Pyx_Py_UNICODE_strlen(u))
-#define __Pyx_PyUnicode_FromUnicodeAndLength PyUnicode_FromUnicode
 #define __Pyx_PyUnicode_AsUnicode            PyUnicode_AsUnicode
 #define __Pyx_NewRef(obj) (Py_INCREF(obj), obj)
 #define __Pyx_Owned_Py_None(b) __Pyx_NewRef(Py_None)
@@ -1620,22 +1641,22 @@ typedef struct {
 /* #### Code section: type_declarations ### */
 
 /*--- Type declarations ---*/
-struct __pyx_obj_9mettagrid_6c_grid_Environment;
+struct __pyx_obj_3env_9mettagrid_6c_grid_Environment;
 struct __pyx_array_obj;
 struct __pyx_MemviewEnum_obj;
 struct __pyx_memoryview_obj;
 struct __pyx_memoryviewslice_obj;
 
-/* "mettagrid/c_grid.pyx":20
+/* "env/mettagrid/c_grid.pyx":20
  *     int WEST = 4
  * 
  * cdef class Environment:             # <<<<<<<<<<<<<<
  *     cdef:
  *         int map_size
  */
-struct __pyx_obj_9mettagrid_6c_grid_Environment {
+struct __pyx_obj_3env_9mettagrid_6c_grid_Environment {
   PyObject_HEAD
-  struct __pyx_vtabstruct_9mettagrid_6c_grid_Environment *__pyx_vtab;
+  struct __pyx_vtabstruct_3env_9mettagrid_6c_grid_Environment *__pyx_vtab;
   int map_size;
   int num_agents;
   int horizon;
@@ -1725,7 +1746,7 @@ struct __pyx_memoryviewslice_obj {
 
 
 
-/* "mettagrid/c_grid.pyx":20
+/* "env/mettagrid/c_grid.pyx":20
  *     int WEST = 4
  * 
  * cdef class Environment:             # <<<<<<<<<<<<<<
@@ -1733,10 +1754,10 @@ struct __pyx_memoryviewslice_obj {
  *         int map_size
  */
 
-struct __pyx_vtabstruct_9mettagrid_6c_grid_Environment {
-  void (*_compute_observations)(struct __pyx_obj_9mettagrid_6c_grid_Environment *);
+struct __pyx_vtabstruct_3env_9mettagrid_6c_grid_Environment {
+  void (*_compute_observations)(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *);
 };
-static struct __pyx_vtabstruct_9mettagrid_6c_grid_Environment *__pyx_vtabptr_9mettagrid_6c_grid_Environment;
+static struct __pyx_vtabstruct_3env_9mettagrid_6c_grid_Environment *__pyx_vtabptr_3env_9mettagrid_6c_grid_Environment;
 
 
 /* "View.MemoryView":114
@@ -2768,17 +2789,17 @@ static PyObject *__pyx_memoryview__get_base(struct __pyx_memoryview_obj *__pyx_v
 static PyObject *__pyx_memoryviewslice_convert_item_to_object(struct __pyx_memoryviewslice_obj *__pyx_v_self, char *__pyx_v_itemp); /* proto*/
 static PyObject *__pyx_memoryviewslice_assign_item_from_object(struct __pyx_memoryviewslice_obj *__pyx_v_self, char *__pyx_v_itemp, PyObject *__pyx_v_value); /* proto*/
 static PyObject *__pyx_memoryviewslice__get_base(struct __pyx_memoryviewslice_obj *__pyx_v_self); /* proto*/
-static void __pyx_f_9mettagrid_6c_grid_11Environment__compute_observations(struct __pyx_obj_9mettagrid_6c_grid_Environment *__pyx_v_self); /* proto*/
-
-/* Module declarations from "mettagrid.c_grid" */
-static int __pyx_v_9mettagrid_6c_grid_EMPTY;
-static int __pyx_v_9mettagrid_6c_grid_AGENT;
-static int __pyx_v_9mettagrid_6c_grid_WALL;
-static int __pyx_v_9mettagrid_6c_grid_PASS;
-static int __pyx_v_9mettagrid_6c_grid_NORTH;
-static int __pyx_v_9mettagrid_6c_grid_SOUTH;
-static int __pyx_v_9mettagrid_6c_grid_EAST;
-static int __pyx_v_9mettagrid_6c_grid_WEST;
+static void __pyx_f_3env_9mettagrid_6c_grid_11Environment__compute_observations(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *__pyx_v_self); /* proto*/
+
+/* Module declarations from "env.mettagrid.c_grid" */
+static int __pyx_v_3env_9mettagrid_6c_grid_EMPTY;
+static int __pyx_v_3env_9mettagrid_6c_grid_AGENT;
+static int __pyx_v_3env_9mettagrid_6c_grid_WALL;
+static int __pyx_v_3env_9mettagrid_6c_grid_PASS;
+static int __pyx_v_3env_9mettagrid_6c_grid_NORTH;
+static int __pyx_v_3env_9mettagrid_6c_grid_SOUTH;
+static int __pyx_v_3env_9mettagrid_6c_grid_EAST;
+static int __pyx_v_3env_9mettagrid_6c_grid_WEST;
 static PyObject *__pyx_collections_abc_Sequence = 0;
 static PyObject *generic = 0;
 static PyObject *strided = 0;
@@ -2787,7 +2808,7 @@ static PyObject *contiguous = 0;
 static PyObject *indirect_contiguous = 0;
 static int __pyx_memoryview_thread_locks_used;
 static PyThread_type_lock __pyx_memoryview_thread_locks[8];
-static PyObject *__pyx_f_9mettagrid_6c_grid___pyx_unpickle_Environment__set_state(struct __pyx_obj_9mettagrid_6c_grid_Environment *, PyObject *); /*proto*/
+static PyObject *__pyx_f_3env_9mettagrid_6c_grid___pyx_unpickle_Environment__set_state(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *, PyObject *); /*proto*/
 static int __pyx_array_allocate_buffer(struct __pyx_array_obj *); /*proto*/
 static struct __pyx_array_obj *__pyx_array_new(PyObject *, Py_ssize_t, char *, char *, char *); /*proto*/
 static PyObject *__pyx_memoryview_new(PyObject *, int, int, __Pyx_TypeInfo *); /*proto*/
@@ -2826,11 +2847,11 @@ static PyObject *__pyx_unpickle_Enum__set_state(struct __pyx_MemviewEnum_obj *,
 static __Pyx_TypeInfo __Pyx_TypeInfo_unsigned_int = { "unsigned int", NULL, sizeof(unsigned int), { 0 }, 0, __PYX_IS_UNSIGNED(unsigned int) ? 'U' : 'I', __PYX_IS_UNSIGNED(unsigned int), 0 };
 static __Pyx_TypeInfo __Pyx_TypeInfo_unsigned_char = { "unsigned char", NULL, sizeof(unsigned char), { 0 }, 0, __PYX_IS_UNSIGNED(unsigned char) ? 'U' : 'I', __PYX_IS_UNSIGNED(unsigned char), 0 };
 /* #### Code section: before_global_var ### */
-#define __Pyx_MODULE_NAME "mettagrid.c_grid"
-extern int __pyx_module_is_main_mettagrid__c_grid;
-int __pyx_module_is_main_mettagrid__c_grid = 0;
+#define __Pyx_MODULE_NAME "env.mettagrid.c_grid"
+extern int __pyx_module_is_main_env__mettagrid__c_grid;
+int __pyx_module_is_main_env__mettagrid__c_grid = 0;
 
-/* Implementation of "mettagrid.c_grid" */
+/* Implementation of "env.mettagrid.c_grid" */
 /* #### Code section: global_var ### */
 static PyObject *__pyx_builtin_range;
 static PyObject *__pyx_builtin_ValueError;
@@ -2954,12 +2975,12 @@ static const char __pyx_k_dtype_is_object[] = "dtype_is_object";
 static const char __pyx_k_pyx_PickleError[] = "__pyx_PickleError";
 static const char __pyx_k_setstate_cython[] = "__setstate_cython__";
 static const char __pyx_k_Environment_step[] = "Environment.step";
-static const char __pyx_k_mettagrid_c_grid[] = "mettagrid.c_grid";
 static const char __pyx_k_Environment_reset[] = "Environment.reset";
 static const char __pyx_k_pyx_unpickle_Enum[] = "__pyx_unpickle_Enum";
 static const char __pyx_k_asyncio_coroutines[] = "asyncio.coroutines";
 static const char __pyx_k_cline_in_traceback[] = "cline_in_traceback";
 static const char __pyx_k_strided_and_direct[] = "<strided and direct>";
+static const char __pyx_k_env_mettagrid_c_grid[] = "env.mettagrid.c_grid";
 static const char __pyx_k_spawn_position_cands[] = "spawn_position_cands";
 static const char __pyx_k_strided_and_indirect[] = "<strided and indirect>";
 static const char __pyx_k_Invalid_shape_in_axis[] = "Invalid shape in axis ";
@@ -3036,13 +3057,13 @@ static void __pyx_memoryviewslice___pyx_pf_15View_dot_MemoryView_16_memoryviewsl
 static PyObject *__pyx_pf___pyx_memoryviewslice___reduce_cython__(CYTHON_UNUSED struct __pyx_memoryviewslice_obj *__pyx_v_self); /* proto */
 static PyObject *__pyx_pf___pyx_memoryviewslice_2__setstate_cython__(CYTHON_UNUSED struct __pyx_memoryviewslice_obj *__pyx_v_self, CYTHON_UNUSED PyObject *__pyx_v___pyx_state); /* proto */
 static PyObject *__pyx_pf_15View_dot_MemoryView___pyx_unpickle_Enum(CYTHON_UNUSED PyObject *__pyx_self, PyObject *__pyx_v___pyx_type, long __pyx_v___pyx_checksum, PyObject *__pyx_v___pyx_state); /* proto */
-static int __pyx_pf_9mettagrid_6c_grid_11Environment___init__(struct __pyx_obj_9mettagrid_6c_grid_Environment *__pyx_v_self, PyObject *__pyx_v_grid, PyObject *__pyx_v_agent_positions, PyObject *__pyx_v_spawn_position_cands, PyObject *__pyx_v_observations, int __pyx_v_map_size, int __pyx_v_num_agents, int __pyx_v_horizon, int __pyx_v_vision_range); /* proto */
-static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_2reset(struct __pyx_obj_9mettagrid_6c_grid_Environment *__pyx_v_self, PyObject *__pyx_v_observations, CYTHON_UNUSED PyObject *__pyx_v_seed); /* proto */
-static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_obj_9mettagrid_6c_grid_Environment *__pyx_v_self, PyObject *__pyx_v_np_actions); /* proto */
-static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_6__reduce_cython__(struct __pyx_obj_9mettagrid_6c_grid_Environment *__pyx_v_self); /* proto */
-static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_8__setstate_cython__(struct __pyx_obj_9mettagrid_6c_grid_Environment *__pyx_v_self, PyObject *__pyx_v___pyx_state); /* proto */
-static PyObject *__pyx_pf_9mettagrid_6c_grid___pyx_unpickle_Environment(CYTHON_UNUSED PyObject *__pyx_self, PyObject *__pyx_v___pyx_type, long __pyx_v___pyx_checksum, PyObject *__pyx_v___pyx_state); /* proto */
-static PyObject *__pyx_tp_new_9mettagrid_6c_grid_Environment(PyTypeObject *t, PyObject *a, PyObject *k); /*proto*/
+static int __pyx_pf_3env_9mettagrid_6c_grid_11Environment___init__(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *__pyx_v_self, PyObject *__pyx_v_grid, PyObject *__pyx_v_agent_positions, PyObject *__pyx_v_spawn_position_cands, PyObject *__pyx_v_observations, int __pyx_v_map_size, int __pyx_v_num_agents, int __pyx_v_horizon, int __pyx_v_vision_range); /* proto */
+static PyObject *__pyx_pf_3env_9mettagrid_6c_grid_11Environment_2reset(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *__pyx_v_self, PyObject *__pyx_v_observations, CYTHON_UNUSED PyObject *__pyx_v_seed); /* proto */
+static PyObject *__pyx_pf_3env_9mettagrid_6c_grid_11Environment_4step(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *__pyx_v_self, PyObject *__pyx_v_np_actions); /* proto */
+static PyObject *__pyx_pf_3env_9mettagrid_6c_grid_11Environment_6__reduce_cython__(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *__pyx_v_self); /* proto */
+static PyObject *__pyx_pf_3env_9mettagrid_6c_grid_11Environment_8__setstate_cython__(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *__pyx_v_self, PyObject *__pyx_v___pyx_state); /* proto */
+static PyObject *__pyx_pf_3env_9mettagrid_6c_grid___pyx_unpickle_Environment(CYTHON_UNUSED PyObject *__pyx_self, PyObject *__pyx_v___pyx_type, long __pyx_v___pyx_checksum, PyObject *__pyx_v___pyx_state); /* proto */
+static PyObject *__pyx_tp_new_3env_9mettagrid_6c_grid_Environment(PyTypeObject *t, PyObject *a, PyObject *k); /*proto*/
 static PyObject *__pyx_tp_new_array(PyTypeObject *t, PyObject *a, PyObject *k); /*proto*/
 static PyObject *__pyx_tp_new_Enum(PyTypeObject *t, PyObject *a, PyObject *k); /*proto*/
 static PyObject *__pyx_tp_new_memoryview(PyTypeObject *t, PyObject *a, PyObject *k); /*proto*/
@@ -3075,13 +3096,13 @@ typedef struct {
   PyTypeObject *__pyx_CoroutineType;
   #endif
   #if CYTHON_USE_MODULE_STATE
-  PyObject *__pyx_type_9mettagrid_6c_grid_Environment;
+  PyObject *__pyx_type_3env_9mettagrid_6c_grid_Environment;
   PyObject *__pyx_type___pyx_array;
   PyObject *__pyx_type___pyx_MemviewEnum;
   PyObject *__pyx_type___pyx_memoryview;
   PyObject *__pyx_type___pyx_memoryviewslice;
   #endif
-  PyTypeObject *__pyx_ptype_9mettagrid_6c_grid_Environment;
+  PyTypeObject *__pyx_ptype_3env_9mettagrid_6c_grid_Environment;
   PyTypeObject *__pyx_array_type;
   PyTypeObject *__pyx_MemviewEnum_type;
   PyTypeObject *__pyx_memoryview_type;
@@ -3159,6 +3180,7 @@ typedef struct {
   PyObject *__pyx_kp_u_enable;
   PyObject *__pyx_n_s_encode;
   PyObject *__pyx_n_s_enumerate;
+  PyObject *__pyx_n_s_env_mettagrid_c_grid;
   PyObject *__pyx_kp_s_env_mettagrid_c_grid_pyx;
   PyObject *__pyx_n_s_error;
   PyObject *__pyx_n_s_flags;
@@ -3183,7 +3205,6 @@ typedef struct {
   PyObject *__pyx_n_s_main;
   PyObject *__pyx_n_s_map_size;
   PyObject *__pyx_n_s_memview;
-  PyObject *__pyx_n_s_mettagrid_c_grid;
   PyObject *__pyx_n_s_mode;
   PyObject *__pyx_n_s_name;
   PyObject *__pyx_n_s_name_2;
@@ -3316,8 +3337,8 @@ static int __pyx_m_clear(PyObject *m) {
   #ifdef __Pyx_FusedFunction_USED
   Py_CLEAR(clear_module_state->__pyx_FusedFunctionType);
   #endif
-  Py_CLEAR(clear_module_state->__pyx_ptype_9mettagrid_6c_grid_Environment);
-  Py_CLEAR(clear_module_state->__pyx_type_9mettagrid_6c_grid_Environment);
+  Py_CLEAR(clear_module_state->__pyx_ptype_3env_9mettagrid_6c_grid_Environment);
+  Py_CLEAR(clear_module_state->__pyx_type_3env_9mettagrid_6c_grid_Environment);
   Py_CLEAR(clear_module_state->__pyx_array_type);
   Py_CLEAR(clear_module_state->__pyx_type___pyx_array);
   Py_CLEAR(clear_module_state->__pyx_MemviewEnum_type);
@@ -3399,6 +3420,7 @@ static int __pyx_m_clear(PyObject *m) {
   Py_CLEAR(clear_module_state->__pyx_kp_u_enable);
   Py_CLEAR(clear_module_state->__pyx_n_s_encode);
   Py_CLEAR(clear_module_state->__pyx_n_s_enumerate);
+  Py_CLEAR(clear_module_state->__pyx_n_s_env_mettagrid_c_grid);
   Py_CLEAR(clear_module_state->__pyx_kp_s_env_mettagrid_c_grid_pyx);
   Py_CLEAR(clear_module_state->__pyx_n_s_error);
   Py_CLEAR(clear_module_state->__pyx_n_s_flags);
@@ -3423,7 +3445,6 @@ static int __pyx_m_clear(PyObject *m) {
   Py_CLEAR(clear_module_state->__pyx_n_s_main);
   Py_CLEAR(clear_module_state->__pyx_n_s_map_size);
   Py_CLEAR(clear_module_state->__pyx_n_s_memview);
-  Py_CLEAR(clear_module_state->__pyx_n_s_mettagrid_c_grid);
   Py_CLEAR(clear_module_state->__pyx_n_s_mode);
   Py_CLEAR(clear_module_state->__pyx_n_s_name);
   Py_CLEAR(clear_module_state->__pyx_n_s_name_2);
@@ -3534,8 +3555,8 @@ static int __pyx_m_traverse(PyObject *m, visitproc visit, void *arg) {
   #ifdef __Pyx_FusedFunction_USED
   Py_VISIT(traverse_module_state->__pyx_FusedFunctionType);
   #endif
-  Py_VISIT(traverse_module_state->__pyx_ptype_9mettagrid_6c_grid_Environment);
-  Py_VISIT(traverse_module_state->__pyx_type_9mettagrid_6c_grid_Environment);
+  Py_VISIT(traverse_module_state->__pyx_ptype_3env_9mettagrid_6c_grid_Environment);
+  Py_VISIT(traverse_module_state->__pyx_type_3env_9mettagrid_6c_grid_Environment);
   Py_VISIT(traverse_module_state->__pyx_array_type);
   Py_VISIT(traverse_module_state->__pyx_type___pyx_array);
   Py_VISIT(traverse_module_state->__pyx_MemviewEnum_type);
@@ -3617,6 +3638,7 @@ static int __pyx_m_traverse(PyObject *m, visitproc visit, void *arg) {
   Py_VISIT(traverse_module_state->__pyx_kp_u_enable);
   Py_VISIT(traverse_module_state->__pyx_n_s_encode);
   Py_VISIT(traverse_module_state->__pyx_n_s_enumerate);
+  Py_VISIT(traverse_module_state->__pyx_n_s_env_mettagrid_c_grid);
   Py_VISIT(traverse_module_state->__pyx_kp_s_env_mettagrid_c_grid_pyx);
   Py_VISIT(traverse_module_state->__pyx_n_s_error);
   Py_VISIT(traverse_module_state->__pyx_n_s_flags);
@@ -3641,7 +3663,6 @@ static int __pyx_m_traverse(PyObject *m, visitproc visit, void *arg) {
   Py_VISIT(traverse_module_state->__pyx_n_s_main);
   Py_VISIT(traverse_module_state->__pyx_n_s_map_size);
   Py_VISIT(traverse_module_state->__pyx_n_s_memview);
-  Py_VISIT(traverse_module_state->__pyx_n_s_mettagrid_c_grid);
   Py_VISIT(traverse_module_state->__pyx_n_s_mode);
   Py_VISIT(traverse_module_state->__pyx_n_s_name);
   Py_VISIT(traverse_module_state->__pyx_n_s_name_2);
@@ -3761,13 +3782,13 @@ static int __pyx_m_traverse(PyObject *m, visitproc visit, void *arg) {
 #define __pyx_CoroutineType __pyx_mstate_global->__pyx_CoroutineType
 #endif
 #if CYTHON_USE_MODULE_STATE
-#define __pyx_type_9mettagrid_6c_grid_Environment __pyx_mstate_global->__pyx_type_9mettagrid_6c_grid_Environment
+#define __pyx_type_3env_9mettagrid_6c_grid_Environment __pyx_mstate_global->__pyx_type_3env_9mettagrid_6c_grid_Environment
 #define __pyx_type___pyx_array __pyx_mstate_global->__pyx_type___pyx_array
 #define __pyx_type___pyx_MemviewEnum __pyx_mstate_global->__pyx_type___pyx_MemviewEnum
 #define __pyx_type___pyx_memoryview __pyx_mstate_global->__pyx_type___pyx_memoryview
 #define __pyx_type___pyx_memoryviewslice __pyx_mstate_global->__pyx_type___pyx_memoryviewslice
 #endif
-#define __pyx_ptype_9mettagrid_6c_grid_Environment __pyx_mstate_global->__pyx_ptype_9mettagrid_6c_grid_Environment
+#define __pyx_ptype_3env_9mettagrid_6c_grid_Environment __pyx_mstate_global->__pyx_ptype_3env_9mettagrid_6c_grid_Environment
 #define __pyx_array_type __pyx_mstate_global->__pyx_array_type
 #define __pyx_MemviewEnum_type __pyx_mstate_global->__pyx_MemviewEnum_type
 #define __pyx_memoryview_type __pyx_mstate_global->__pyx_memoryview_type
@@ -3845,6 +3866,7 @@ static int __pyx_m_traverse(PyObject *m, visitproc visit, void *arg) {
 #define __pyx_kp_u_enable __pyx_mstate_global->__pyx_kp_u_enable
 #define __pyx_n_s_encode __pyx_mstate_global->__pyx_n_s_encode
 #define __pyx_n_s_enumerate __pyx_mstate_global->__pyx_n_s_enumerate
+#define __pyx_n_s_env_mettagrid_c_grid __pyx_mstate_global->__pyx_n_s_env_mettagrid_c_grid
 #define __pyx_kp_s_env_mettagrid_c_grid_pyx __pyx_mstate_global->__pyx_kp_s_env_mettagrid_c_grid_pyx
 #define __pyx_n_s_error __pyx_mstate_global->__pyx_n_s_error
 #define __pyx_n_s_flags __pyx_mstate_global->__pyx_n_s_flags
@@ -3869,7 +3891,6 @@ static int __pyx_m_traverse(PyObject *m, visitproc visit, void *arg) {
 #define __pyx_n_s_main __pyx_mstate_global->__pyx_n_s_main
 #define __pyx_n_s_map_size __pyx_mstate_global->__pyx_n_s_map_size
 #define __pyx_n_s_memview __pyx_mstate_global->__pyx_n_s_memview
-#define __pyx_n_s_mettagrid_c_grid __pyx_mstate_global->__pyx_n_s_mettagrid_c_grid
 #define __pyx_n_s_mode __pyx_mstate_global->__pyx_n_s_mode
 #define __pyx_n_s_name __pyx_mstate_global->__pyx_n_s_name
 #define __pyx_n_s_name_2 __pyx_mstate_global->__pyx_n_s_name_2
@@ -17588,7 +17609,7 @@ static PyObject *__pyx_unpickle_Enum__set_state(struct __pyx_MemviewEnum_obj *__
   return __pyx_r;
 }
 
-/* "mettagrid/c_grid.pyx":33
+/* "env/mettagrid/c_grid.pyx":33
  *         unsigned int[:, :] spawn_position_cands
  * 
  *     def __init__(self, grid, agent_positions, spawn_position_cands, observations,             # <<<<<<<<<<<<<<
@@ -17597,8 +17618,8 @@ static PyObject *__pyx_unpickle_Enum__set_state(struct __pyx_MemviewEnum_obj *__
  */
 
 /* Python wrapper */
-static int __pyx_pw_9mettagrid_6c_grid_11Environment_1__init__(PyObject *__pyx_v_self, PyObject *__pyx_args, PyObject *__pyx_kwds); /*proto*/
-static int __pyx_pw_9mettagrid_6c_grid_11Environment_1__init__(PyObject *__pyx_v_self, PyObject *__pyx_args, PyObject *__pyx_kwds) {
+static int __pyx_pw_3env_9mettagrid_6c_grid_11Environment_1__init__(PyObject *__pyx_v_self, PyObject *__pyx_args, PyObject *__pyx_kwds); /*proto*/
+static int __pyx_pw_3env_9mettagrid_6c_grid_11Environment_1__init__(PyObject *__pyx_v_self, PyObject *__pyx_args, PyObject *__pyx_kwds) {
   PyObject *__pyx_v_grid = 0;
   PyObject *__pyx_v_agent_positions = 0;
   PyObject *__pyx_v_spawn_position_cands = 0;
@@ -17763,11 +17784,11 @@ static int __pyx_pw_9mettagrid_6c_grid_11Environment_1__init__(PyObject *__pyx_v
       __Pyx_Arg_XDECREF_VARARGS(values[__pyx_temp]);
     }
   }
-  __Pyx_AddTraceback("mettagrid.c_grid.Environment.__init__", __pyx_clineno, __pyx_lineno, __pyx_filename);
+  __Pyx_AddTraceback("env.mettagrid.c_grid.Environment.__init__", __pyx_clineno, __pyx_lineno, __pyx_filename);
   __Pyx_RefNannyFinishContext();
   return -1;
   __pyx_L4_argument_unpacking_done:;
-  __pyx_r = __pyx_pf_9mettagrid_6c_grid_11Environment___init__(((struct __pyx_obj_9mettagrid_6c_grid_Environment *)__pyx_v_self), __pyx_v_grid, __pyx_v_agent_positions, __pyx_v_spawn_position_cands, __pyx_v_observations, __pyx_v_map_size, __pyx_v_num_agents, __pyx_v_horizon, __pyx_v_vision_range);
+  __pyx_r = __pyx_pf_3env_9mettagrid_6c_grid_11Environment___init__(((struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *)__pyx_v_self), __pyx_v_grid, __pyx_v_agent_positions, __pyx_v_spawn_position_cands, __pyx_v_observations, __pyx_v_map_size, __pyx_v_num_agents, __pyx_v_horizon, __pyx_v_vision_range);
 
   /* function exit code */
   {
@@ -17780,7 +17801,7 @@ static int __pyx_pw_9mettagrid_6c_grid_11Environment_1__init__(PyObject *__pyx_v
   return __pyx_r;
 }
 
-static int __pyx_pf_9mettagrid_6c_grid_11Environment___init__(struct __pyx_obj_9mettagrid_6c_grid_Environment *__pyx_v_self, PyObject *__pyx_v_grid, PyObject *__pyx_v_agent_positions, PyObject *__pyx_v_spawn_position_cands, PyObject *__pyx_v_observations, int __pyx_v_map_size, int __pyx_v_num_agents, int __pyx_v_horizon, int __pyx_v_vision_range) {
+static int __pyx_pf_3env_9mettagrid_6c_grid_11Environment___init__(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *__pyx_v_self, PyObject *__pyx_v_grid, PyObject *__pyx_v_agent_positions, PyObject *__pyx_v_spawn_position_cands, PyObject *__pyx_v_observations, int __pyx_v_map_size, int __pyx_v_num_agents, int __pyx_v_horizon, int __pyx_v_vision_range) {
   int __pyx_r;
   __Pyx_memviewslice __pyx_t_1 = { 0, 0, { 0 }, { 0 }, { 0 } };
   __Pyx_memviewslice __pyx_t_2 = { 0, 0, { 0 }, { 0 }, { 0 } };
@@ -17789,7 +17810,7 @@ static int __pyx_pf_9mettagrid_6c_grid_11Environment___init__(struct __pyx_obj_9
   const char *__pyx_filename = NULL;
   int __pyx_clineno = 0;
 
-  /* "mettagrid/c_grid.pyx":35
+  /* "env/mettagrid/c_grid.pyx":35
  *     def __init__(self, grid, agent_positions, spawn_position_cands, observations,
  *             int map_size, int num_agents, int horizon, int vision_range):
  *         self.map_size = map_size             # <<<<<<<<<<<<<<
@@ -17798,7 +17819,7 @@ static int __pyx_pf_9mettagrid_6c_grid_11Environment___init__(struct __pyx_obj_9
  */
   __pyx_v_self->map_size = __pyx_v_map_size;
 
-  /* "mettagrid/c_grid.pyx":36
+  /* "env/mettagrid/c_grid.pyx":36
  *             int map_size, int num_agents, int horizon, int vision_range):
  *         self.map_size = map_size
  *         self.num_agents = num_agents             # <<<<<<<<<<<<<<
@@ -17807,7 +17828,7 @@ static int __pyx_pf_9mettagrid_6c_grid_11Environment___init__(struct __pyx_obj_9
  */
   __pyx_v_self->num_agents = __pyx_v_num_agents;
 
-  /* "mettagrid/c_grid.pyx":37
+  /* "env/mettagrid/c_grid.pyx":37
  *         self.map_size = map_size
  *         self.num_agents = num_agents
  *         self.horizon = horizon             # <<<<<<<<<<<<<<
@@ -17816,7 +17837,7 @@ static int __pyx_pf_9mettagrid_6c_grid_11Environment___init__(struct __pyx_obj_9
  */
   __pyx_v_self->horizon = __pyx_v_horizon;
 
-  /* "mettagrid/c_grid.pyx":38
+  /* "env/mettagrid/c_grid.pyx":38
  *         self.num_agents = num_agents
  *         self.horizon = horizon
  *         self.vision_range = vision_range             # <<<<<<<<<<<<<<
@@ -17825,7 +17846,7 @@ static int __pyx_pf_9mettagrid_6c_grid_11Environment___init__(struct __pyx_obj_9
  */
   __pyx_v_self->vision_range = __pyx_v_vision_range;
 
-  /* "mettagrid/c_grid.pyx":39
+  /* "env/mettagrid/c_grid.pyx":39
  *         self.horizon = horizon
  *         self.vision_range = vision_range
  *         self.obs_size = 2*self.vision_range + 1             # <<<<<<<<<<<<<<
@@ -17834,7 +17855,7 @@ static int __pyx_pf_9mettagrid_6c_grid_11Environment___init__(struct __pyx_obj_9
  */
   __pyx_v_self->obs_size = ((2 * __pyx_v_self->vision_range) + 1);
 
-  /* "mettagrid/c_grid.pyx":41
+  /* "env/mettagrid/c_grid.pyx":41
  *         self.obs_size = 2*self.vision_range + 1
  * 
  *         self.grid = grid             # <<<<<<<<<<<<<<
@@ -17847,7 +17868,7 @@ static int __pyx_pf_9mettagrid_6c_grid_11Environment___init__(struct __pyx_obj_9
   __pyx_t_1.memview = NULL;
   __pyx_t_1.data = NULL;
 
-  /* "mettagrid/c_grid.pyx":42
+  /* "env/mettagrid/c_grid.pyx":42
  * 
  *         self.grid = grid
  *         self.observations = observations             # <<<<<<<<<<<<<<
@@ -17860,7 +17881,7 @@ static int __pyx_pf_9mettagrid_6c_grid_11Environment___init__(struct __pyx_obj_9
   __pyx_t_2.memview = NULL;
   __pyx_t_2.data = NULL;
 
-  /* "mettagrid/c_grid.pyx":43
+  /* "env/mettagrid/c_grid.pyx":43
  *         self.grid = grid
  *         self.observations = observations
  *         self.agent_positions = agent_positions             # <<<<<<<<<<<<<<
@@ -17873,7 +17894,7 @@ static int __pyx_pf_9mettagrid_6c_grid_11Environment___init__(struct __pyx_obj_9
   __pyx_t_3.memview = NULL;
   __pyx_t_3.data = NULL;
 
-  /* "mettagrid/c_grid.pyx":44
+  /* "env/mettagrid/c_grid.pyx":44
  *         self.observations = observations
  *         self.agent_positions = agent_positions
  *         self.spawn_position_cands = spawn_position_cands             # <<<<<<<<<<<<<<
@@ -17886,7 +17907,7 @@ static int __pyx_pf_9mettagrid_6c_grid_11Environment___init__(struct __pyx_obj_9
   __pyx_t_3.memview = NULL;
   __pyx_t_3.data = NULL;
 
-  /* "mettagrid/c_grid.pyx":33
+  /* "env/mettagrid/c_grid.pyx":33
  *         unsigned int[:, :] spawn_position_cands
  * 
  *     def __init__(self, grid, agent_positions, spawn_position_cands, observations,             # <<<<<<<<<<<<<<
@@ -17901,13 +17922,13 @@ static int __pyx_pf_9mettagrid_6c_grid_11Environment___init__(struct __pyx_obj_9
   __PYX_XCLEAR_MEMVIEW(&__pyx_t_1, 1);
   __PYX_XCLEAR_MEMVIEW(&__pyx_t_2, 1);
   __PYX_XCLEAR_MEMVIEW(&__pyx_t_3, 1);
-  __Pyx_AddTraceback("mettagrid.c_grid.Environment.__init__", __pyx_clineno, __pyx_lineno, __pyx_filename);
+  __Pyx_AddTraceback("env.mettagrid.c_grid.Environment.__init__", __pyx_clineno, __pyx_lineno, __pyx_filename);
   __pyx_r = -1;
   __pyx_L0:;
   return __pyx_r;
 }
 
-/* "mettagrid/c_grid.pyx":46
+/* "env/mettagrid/c_grid.pyx":46
  *         self.spawn_position_cands = spawn_position_cands
  * 
  *     cdef void _compute_observations(self):             # <<<<<<<<<<<<<<
@@ -17915,7 +17936,7 @@ static int __pyx_pf_9mettagrid_6c_grid_11Environment___init__(struct __pyx_obj_9
  *         for agent_idx in range(self.num_agents):
  */
 
-static void __pyx_f_9mettagrid_6c_grid_11Environment__compute_observations(struct __pyx_obj_9mettagrid_6c_grid_Environment *__pyx_v_self) {
+static void __pyx_f_3env_9mettagrid_6c_grid_11Environment__compute_observations(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *__pyx_v_self) {
   int __pyx_v_r;
   int __pyx_v_c;
   int __pyx_v_agent_idx;
@@ -17931,7 +17952,7 @@ static void __pyx_f_9mettagrid_6c_grid_11Environment__compute_observations(struc
   const char *__pyx_filename = NULL;
   int __pyx_clineno = 0;
 
-  /* "mettagrid/c_grid.pyx":48
+  /* "env/mettagrid/c_grid.pyx":48
  *     cdef void _compute_observations(self):
  *         cdef int r, c, agent_idx
  *         for agent_idx in range(self.num_agents):             # <<<<<<<<<<<<<<
@@ -17943,7 +17964,7 @@ static void __pyx_f_9mettagrid_6c_grid_11Environment__compute_observations(struc
   for (__pyx_t_3 = 0; __pyx_t_3 < __pyx_t_2; __pyx_t_3+=1) {
     __pyx_v_agent_idx = __pyx_t_3;
 
-    /* "mettagrid/c_grid.pyx":49
+    /* "env/mettagrid/c_grid.pyx":49
  *         cdef int r, c, agent_idx
  *         for agent_idx in range(self.num_agents):
  *             r = self.agent_positions[agent_idx, 0]             # <<<<<<<<<<<<<<
@@ -17954,7 +17975,7 @@ static void __pyx_f_9mettagrid_6c_grid_11Environment__compute_observations(struc
     __pyx_t_5 = 0;
     __pyx_v_r = (*((unsigned int *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->agent_positions.data + __pyx_t_4 * __pyx_v_self->agent_positions.strides[0]) ) + __pyx_t_5 * __pyx_v_self->agent_positions.strides[1]) )));
 
-    /* "mettagrid/c_grid.pyx":50
+    /* "env/mettagrid/c_grid.pyx":50
  *         for agent_idx in range(self.num_agents):
  *             r = self.agent_positions[agent_idx, 0]
  *             c = self.agent_positions[agent_idx, 1]             # <<<<<<<<<<<<<<
@@ -17965,7 +17986,7 @@ static void __pyx_f_9mettagrid_6c_grid_11Environment__compute_observations(struc
     __pyx_t_4 = 1;
     __pyx_v_c = (*((unsigned int *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->agent_positions.data + __pyx_t_5 * __pyx_v_self->agent_positions.strides[0]) ) + __pyx_t_4 * __pyx_v_self->agent_positions.strides[1]) )));
 
-    /* "mettagrid/c_grid.pyx":51
+    /* "env/mettagrid/c_grid.pyx":51
  *             r = self.agent_positions[agent_idx, 0]
  *             c = self.agent_positions[agent_idx, 1]
  *             self.observations[agent_idx, :] = self.grid[             # <<<<<<<<<<<<<<
@@ -18034,7 +18055,7 @@ if (unlikely((__pyx_memoryview_copy_contents(__pyx_t_6, __pyx_t_8, 2, 2, 0) < 0)
     __pyx_t_6.memview = NULL; __pyx_t_6.data = NULL;
   }
 
-  /* "mettagrid/c_grid.pyx":46
+  /* "env/mettagrid/c_grid.pyx":46
  *         self.spawn_position_cands = spawn_position_cands
  * 
  *     cdef void _compute_observations(self):             # <<<<<<<<<<<<<<
@@ -18047,11 +18068,11 @@ if (unlikely((__pyx_memoryview_copy_contents(__pyx_t_6, __pyx_t_8, 2, 2, 0) < 0)
   __pyx_L1_error:;
   __PYX_XCLEAR_MEMVIEW(&__pyx_t_6, 1);
   __PYX_XCLEAR_MEMVIEW(&__pyx_t_8, 1);
-  __Pyx_AddTraceback("mettagrid.c_grid.Environment._compute_observations", __pyx_clineno, __pyx_lineno, __pyx_filename);
+  __Pyx_AddTraceback("env.mettagrid.c_grid.Environment._compute_observations", __pyx_clineno, __pyx_lineno, __pyx_filename);
   __pyx_L0:;
 }
 
-/* "mettagrid/c_grid.pyx":56
+/* "env/mettagrid/c_grid.pyx":56
  *             ]
  * 
  *     def reset(self, observations, seed=0):             # <<<<<<<<<<<<<<
@@ -18060,15 +18081,15 @@ if (unlikely((__pyx_memoryview_copy_contents(__pyx_t_6, __pyx_t_8, 2, 2, 0) < 0)
  */
 
 /* Python wrapper */
-static PyObject *__pyx_pw_9mettagrid_6c_grid_11Environment_3reset(PyObject *__pyx_v_self, 
+static PyObject *__pyx_pw_3env_9mettagrid_6c_grid_11Environment_3reset(PyObject *__pyx_v_self, 
 #if CYTHON_METH_FASTCALL
 PyObject *const *__pyx_args, Py_ssize_t __pyx_nargs, PyObject *__pyx_kwds
 #else
 PyObject *__pyx_args, PyObject *__pyx_kwds
 #endif
 ); /*proto*/
-static PyMethodDef __pyx_mdef_9mettagrid_6c_grid_11Environment_3reset = {"reset", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_9mettagrid_6c_grid_11Environment_3reset, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0};
-static PyObject *__pyx_pw_9mettagrid_6c_grid_11Environment_3reset(PyObject *__pyx_v_self, 
+static PyMethodDef __pyx_mdef_3env_9mettagrid_6c_grid_11Environment_3reset = {"reset", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_3env_9mettagrid_6c_grid_11Environment_3reset, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0};
+static PyObject *__pyx_pw_3env_9mettagrid_6c_grid_11Environment_3reset(PyObject *__pyx_v_self, 
 #if CYTHON_METH_FASTCALL
 PyObject *const *__pyx_args, Py_ssize_t __pyx_nargs, PyObject *__pyx_kwds
 #else
@@ -18154,11 +18175,11 @@ PyObject *__pyx_args, PyObject *__pyx_kwds
       __Pyx_Arg_XDECREF_FASTCALL(values[__pyx_temp]);
     }
   }
-  __Pyx_AddTraceback("mettagrid.c_grid.Environment.reset", __pyx_clineno, __pyx_lineno, __pyx_filename);
+  __Pyx_AddTraceback("env.mettagrid.c_grid.Environment.reset", __pyx_clineno, __pyx_lineno, __pyx_filename);
   __Pyx_RefNannyFinishContext();
   return NULL;
   __pyx_L4_argument_unpacking_done:;
-  __pyx_r = __pyx_pf_9mettagrid_6c_grid_11Environment_2reset(((struct __pyx_obj_9mettagrid_6c_grid_Environment *)__pyx_v_self), __pyx_v_observations, __pyx_v_seed);
+  __pyx_r = __pyx_pf_3env_9mettagrid_6c_grid_11Environment_2reset(((struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *)__pyx_v_self), __pyx_v_observations, __pyx_v_seed);
 
   /* function exit code */
   {
@@ -18171,7 +18192,7 @@ PyObject *__pyx_args, PyObject *__pyx_kwds
   return __pyx_r;
 }
 
-static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_2reset(struct __pyx_obj_9mettagrid_6c_grid_Environment *__pyx_v_self, PyObject *__pyx_v_observations, CYTHON_UNUSED PyObject *__pyx_v_seed) {
+static PyObject *__pyx_pf_3env_9mettagrid_6c_grid_11Environment_2reset(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *__pyx_v_self, PyObject *__pyx_v_observations, CYTHON_UNUSED PyObject *__pyx_v_seed) {
   int __pyx_v_left;
   int __pyx_v_right;
   int __pyx_v_spawn_idx;
@@ -18193,7 +18214,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_2reset(struct __pyx_o
   int __pyx_clineno = 0;
   __Pyx_RefNannySetupContext("reset", 1);
 
-  /* "mettagrid/c_grid.pyx":57
+  /* "env/mettagrid/c_grid.pyx":57
  * 
  *     def reset(self, observations, seed=0):
  *         self.observations = observations             # <<<<<<<<<<<<<<
@@ -18206,7 +18227,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_2reset(struct __pyx_o
   __pyx_t_1.memview = NULL;
   __pyx_t_1.data = NULL;
 
-  /* "mettagrid/c_grid.pyx":60
+  /* "env/mettagrid/c_grid.pyx":60
  * 
  *         # Add borders
  *         cdef int left = self.vision_range             # <<<<<<<<<<<<<<
@@ -18216,7 +18237,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_2reset(struct __pyx_o
   __pyx_t_2 = __pyx_v_self->vision_range;
   __pyx_v_left = __pyx_t_2;
 
-  /* "mettagrid/c_grid.pyx":61
+  /* "env/mettagrid/c_grid.pyx":61
  *         # Add borders
  *         cdef int left = self.vision_range
  *         cdef int right = self.map_size - self.vision_range - 1             # <<<<<<<<<<<<<<
@@ -18225,7 +18246,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_2reset(struct __pyx_o
  */
   __pyx_v_right = ((__pyx_v_self->map_size - __pyx_v_self->vision_range) - 1);
 
-  /* "mettagrid/c_grid.pyx":62
+  /* "env/mettagrid/c_grid.pyx":62
  *         cdef int left = self.vision_range
  *         cdef int right = self.map_size - self.vision_range - 1
  *         self.grid[:left, :] = WALL             # <<<<<<<<<<<<<<
@@ -18258,7 +18279,7 @@ __pyx_t_3.strides[1] = __pyx_v_self->grid.strides[1];
     __pyx_t_3.suboffsets[1] = -1;
 
 {
-      unsigned char __pyx_temp_scalar = __pyx_v_9mettagrid_6c_grid_WALL;
+      unsigned char __pyx_temp_scalar = __pyx_v_3env_9mettagrid_6c_grid_WALL;
       {
           Py_ssize_t __pyx_temp_extent_0 = __pyx_t_3.shape[0];
           Py_ssize_t __pyx_temp_stride_0 = __pyx_t_3.strides[0];
@@ -18282,7 +18303,7 @@ __pyx_t_3.strides[1] = __pyx_v_self->grid.strides[1];
   __PYX_XCLEAR_MEMVIEW(&__pyx_t_3, 1);
   __pyx_t_3.memview = NULL; __pyx_t_3.data = NULL;
 
-  /* "mettagrid/c_grid.pyx":63
+  /* "env/mettagrid/c_grid.pyx":63
  *         cdef int right = self.map_size - self.vision_range - 1
  *         self.grid[:left, :] = WALL
  *         self.grid[right:, :] = WALL             # <<<<<<<<<<<<<<
@@ -18315,7 +18336,7 @@ __pyx_t_3.strides[1] = __pyx_v_self->grid.strides[1];
     __pyx_t_3.suboffsets[1] = -1;
 
 {
-      unsigned char __pyx_temp_scalar = __pyx_v_9mettagrid_6c_grid_WALL;
+      unsigned char __pyx_temp_scalar = __pyx_v_3env_9mettagrid_6c_grid_WALL;
       {
           Py_ssize_t __pyx_temp_extent_0 = __pyx_t_3.shape[0];
           Py_ssize_t __pyx_temp_stride_0 = __pyx_t_3.strides[0];
@@ -18339,7 +18360,7 @@ __pyx_t_3.strides[1] = __pyx_v_self->grid.strides[1];
   __PYX_XCLEAR_MEMVIEW(&__pyx_t_3, 1);
   __pyx_t_3.memview = NULL; __pyx_t_3.data = NULL;
 
-  /* "mettagrid/c_grid.pyx":64
+  /* "env/mettagrid/c_grid.pyx":64
  *         self.grid[:left, :] = WALL
  *         self.grid[right:, :] = WALL
  *         self.grid[:, :left] = WALL             # <<<<<<<<<<<<<<
@@ -18372,7 +18393,7 @@ __pyx_t_2 = -1;
 }
 
 {
-      unsigned char __pyx_temp_scalar = __pyx_v_9mettagrid_6c_grid_WALL;
+      unsigned char __pyx_temp_scalar = __pyx_v_3env_9mettagrid_6c_grid_WALL;
       {
           Py_ssize_t __pyx_temp_extent_0 = __pyx_t_3.shape[0];
           Py_ssize_t __pyx_temp_stride_0 = __pyx_t_3.strides[0];
@@ -18396,7 +18417,7 @@ __pyx_t_2 = -1;
   __PYX_XCLEAR_MEMVIEW(&__pyx_t_3, 1);
   __pyx_t_3.memview = NULL; __pyx_t_3.data = NULL;
 
-  /* "mettagrid/c_grid.pyx":65
+  /* "env/mettagrid/c_grid.pyx":65
  *         self.grid[right:, :] = WALL
  *         self.grid[:, :left] = WALL
  *         self.grid[:, right:] = WALL             # <<<<<<<<<<<<<<
@@ -18429,7 +18450,7 @@ __pyx_t_2 = -1;
 }
 
 {
-      unsigned char __pyx_temp_scalar = __pyx_v_9mettagrid_6c_grid_WALL;
+      unsigned char __pyx_temp_scalar = __pyx_v_3env_9mettagrid_6c_grid_WALL;
       {
           Py_ssize_t __pyx_temp_extent_0 = __pyx_t_3.shape[0];
           Py_ssize_t __pyx_temp_stride_0 = __pyx_t_3.strides[0];
@@ -18453,7 +18474,7 @@ __pyx_t_2 = -1;
   __PYX_XCLEAR_MEMVIEW(&__pyx_t_3, 1);
   __pyx_t_3.memview = NULL; __pyx_t_3.data = NULL;
 
-  /* "mettagrid/c_grid.pyx":69
+  /* "env/mettagrid/c_grid.pyx":69
  *         # Agent spawning
  *         cdef int spawn_idx, r, c
  *         cdef int agent_idx = 0             # <<<<<<<<<<<<<<
@@ -18462,7 +18483,7 @@ __pyx_t_2 = -1;
  */
   __pyx_v_agent_idx = 0;
 
-  /* "mettagrid/c_grid.pyx":70
+  /* "env/mettagrid/c_grid.pyx":70
  *         cdef int spawn_idx, r, c
  *         cdef int agent_idx = 0
  *         for spawn_idx in range(self.map_size**2):             # <<<<<<<<<<<<<<
@@ -18474,7 +18495,7 @@ __pyx_t_2 = -1;
   for (__pyx_t_2 = 0; __pyx_t_2 < __pyx_t_5; __pyx_t_2+=1) {
     __pyx_v_spawn_idx = __pyx_t_2;
 
-    /* "mettagrid/c_grid.pyx":71
+    /* "env/mettagrid/c_grid.pyx":71
  *         cdef int agent_idx = 0
  *         for spawn_idx in range(self.map_size**2):
  *             r = self.spawn_position_cands[spawn_idx, 0]             # <<<<<<<<<<<<<<
@@ -18485,7 +18506,7 @@ __pyx_t_2 = -1;
     __pyx_t_7 = 0;
     __pyx_v_r = (*((unsigned int *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->spawn_position_cands.data + __pyx_t_6 * __pyx_v_self->spawn_position_cands.strides[0]) ) + __pyx_t_7 * __pyx_v_self->spawn_position_cands.strides[1]) )));
 
-    /* "mettagrid/c_grid.pyx":72
+    /* "env/mettagrid/c_grid.pyx":72
  *         for spawn_idx in range(self.map_size**2):
  *             r = self.spawn_position_cands[spawn_idx, 0]
  *             c = self.spawn_position_cands[spawn_idx, 1]             # <<<<<<<<<<<<<<
@@ -18496,7 +18517,7 @@ __pyx_t_2 = -1;
     __pyx_t_6 = 1;
     __pyx_v_c = (*((unsigned int *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->spawn_position_cands.data + __pyx_t_7 * __pyx_v_self->spawn_position_cands.strides[0]) ) + __pyx_t_6 * __pyx_v_self->spawn_position_cands.strides[1]) )));
 
-    /* "mettagrid/c_grid.pyx":73
+    /* "env/mettagrid/c_grid.pyx":73
  *             r = self.spawn_position_cands[spawn_idx, 0]
  *             c = self.spawn_position_cands[spawn_idx, 1]
  *             if self.grid[r, c] == 0:             # <<<<<<<<<<<<<<
@@ -18508,7 +18529,7 @@ __pyx_t_2 = -1;
     __pyx_t_8 = ((*((unsigned char *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->grid.data + __pyx_t_6 * __pyx_v_self->grid.strides[0]) ) + __pyx_t_7 * __pyx_v_self->grid.strides[1]) ))) == 0);
     if (__pyx_t_8) {
 
-      /* "mettagrid/c_grid.pyx":74
+      /* "env/mettagrid/c_grid.pyx":74
  *             c = self.spawn_position_cands[spawn_idx, 1]
  *             if self.grid[r, c] == 0:
  *                 self.grid[r, c] = AGENT             # <<<<<<<<<<<<<<
@@ -18517,9 +18538,9 @@ __pyx_t_2 = -1;
  */
       __pyx_t_7 = __pyx_v_r;
       __pyx_t_6 = __pyx_v_c;
-      *((unsigned char *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->grid.data + __pyx_t_7 * __pyx_v_self->grid.strides[0]) ) + __pyx_t_6 * __pyx_v_self->grid.strides[1]) )) = __pyx_v_9mettagrid_6c_grid_AGENT;
+      *((unsigned char *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->grid.data + __pyx_t_7 * __pyx_v_self->grid.strides[0]) ) + __pyx_t_6 * __pyx_v_self->grid.strides[1]) )) = __pyx_v_3env_9mettagrid_6c_grid_AGENT;
 
-      /* "mettagrid/c_grid.pyx":75
+      /* "env/mettagrid/c_grid.pyx":75
  *             if self.grid[r, c] == 0:
  *                 self.grid[r, c] = AGENT
  *                 self.agent_positions[agent_idx, 0] = r             # <<<<<<<<<<<<<<
@@ -18530,7 +18551,7 @@ __pyx_t_2 = -1;
       __pyx_t_7 = 0;
       *((unsigned int *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->agent_positions.data + __pyx_t_6 * __pyx_v_self->agent_positions.strides[0]) ) + __pyx_t_7 * __pyx_v_self->agent_positions.strides[1]) )) = __pyx_v_r;
 
-      /* "mettagrid/c_grid.pyx":76
+      /* "env/mettagrid/c_grid.pyx":76
  *                 self.grid[r, c] = AGENT
  *                 self.agent_positions[agent_idx, 0] = r
  *                 self.agent_positions[agent_idx, 1] = c             # <<<<<<<<<<<<<<
@@ -18541,7 +18562,7 @@ __pyx_t_2 = -1;
       __pyx_t_6 = 1;
       *((unsigned int *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->agent_positions.data + __pyx_t_7 * __pyx_v_self->agent_positions.strides[0]) ) + __pyx_t_6 * __pyx_v_self->agent_positions.strides[1]) )) = __pyx_v_c;
 
-      /* "mettagrid/c_grid.pyx":77
+      /* "env/mettagrid/c_grid.pyx":77
  *                 self.agent_positions[agent_idx, 0] = r
  *                 self.agent_positions[agent_idx, 1] = c
  *                 agent_idx += 1             # <<<<<<<<<<<<<<
@@ -18550,7 +18571,7 @@ __pyx_t_2 = -1;
  */
       __pyx_v_agent_idx = (__pyx_v_agent_idx + 1);
 
-      /* "mettagrid/c_grid.pyx":78
+      /* "env/mettagrid/c_grid.pyx":78
  *                 self.agent_positions[agent_idx, 1] = c
  *                 agent_idx += 1
  *                 if agent_idx == self.num_agents:             # <<<<<<<<<<<<<<
@@ -18560,7 +18581,7 @@ __pyx_t_2 = -1;
       __pyx_t_8 = (__pyx_v_agent_idx == __pyx_v_self->num_agents);
       if (__pyx_t_8) {
 
-        /* "mettagrid/c_grid.pyx":79
+        /* "env/mettagrid/c_grid.pyx":79
  *                 agent_idx += 1
  *                 if agent_idx == self.num_agents:
  *                     break             # <<<<<<<<<<<<<<
@@ -18569,7 +18590,7 @@ __pyx_t_2 = -1;
  */
         goto __pyx_L4_break;
 
-        /* "mettagrid/c_grid.pyx":78
+        /* "env/mettagrid/c_grid.pyx":78
  *                 self.agent_positions[agent_idx, 1] = c
  *                 agent_idx += 1
  *                 if agent_idx == self.num_agents:             # <<<<<<<<<<<<<<
@@ -18578,7 +18599,7 @@ __pyx_t_2 = -1;
  */
       }
 
-      /* "mettagrid/c_grid.pyx":73
+      /* "env/mettagrid/c_grid.pyx":73
  *             r = self.spawn_position_cands[spawn_idx, 0]
  *             c = self.spawn_position_cands[spawn_idx, 1]
  *             if self.grid[r, c] == 0:             # <<<<<<<<<<<<<<
@@ -18589,16 +18610,16 @@ __pyx_t_2 = -1;
   }
   __pyx_L4_break:;
 
-  /* "mettagrid/c_grid.pyx":81
+  /* "env/mettagrid/c_grid.pyx":81
  *                     break
  * 
  *         self._compute_observations()             # <<<<<<<<<<<<<<
  * 
  *     def step(self, np_actions):
  */
-  ((struct __pyx_vtabstruct_9mettagrid_6c_grid_Environment *)__pyx_v_self->__pyx_vtab)->_compute_observations(__pyx_v_self); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 81, __pyx_L1_error)
+  ((struct __pyx_vtabstruct_3env_9mettagrid_6c_grid_Environment *)__pyx_v_self->__pyx_vtab)->_compute_observations(__pyx_v_self); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 81, __pyx_L1_error)
 
-  /* "mettagrid/c_grid.pyx":56
+  /* "env/mettagrid/c_grid.pyx":56
  *             ]
  * 
  *     def reset(self, observations, seed=0):             # <<<<<<<<<<<<<<
@@ -18612,7 +18633,7 @@ __pyx_t_2 = -1;
   __pyx_L1_error:;
   __PYX_XCLEAR_MEMVIEW(&__pyx_t_1, 1);
   __PYX_XCLEAR_MEMVIEW(&__pyx_t_3, 1);
-  __Pyx_AddTraceback("mettagrid.c_grid.Environment.reset", __pyx_clineno, __pyx_lineno, __pyx_filename);
+  __Pyx_AddTraceback("env.mettagrid.c_grid.Environment.reset", __pyx_clineno, __pyx_lineno, __pyx_filename);
   __pyx_r = NULL;
   __pyx_L0:;
   __Pyx_XGIVEREF(__pyx_r);
@@ -18620,7 +18641,7 @@ __pyx_t_2 = -1;
   return __pyx_r;
 }
 
-/* "mettagrid/c_grid.pyx":83
+/* "env/mettagrid/c_grid.pyx":83
  *         self._compute_observations()
  * 
  *     def step(self, np_actions):             # <<<<<<<<<<<<<<
@@ -18629,15 +18650,15 @@ __pyx_t_2 = -1;
  */
 
 /* Python wrapper */
-static PyObject *__pyx_pw_9mettagrid_6c_grid_11Environment_5step(PyObject *__pyx_v_self, 
+static PyObject *__pyx_pw_3env_9mettagrid_6c_grid_11Environment_5step(PyObject *__pyx_v_self, 
 #if CYTHON_METH_FASTCALL
 PyObject *const *__pyx_args, Py_ssize_t __pyx_nargs, PyObject *__pyx_kwds
 #else
 PyObject *__pyx_args, PyObject *__pyx_kwds
 #endif
 ); /*proto*/
-static PyMethodDef __pyx_mdef_9mettagrid_6c_grid_11Environment_5step = {"step", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_9mettagrid_6c_grid_11Environment_5step, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0};
-static PyObject *__pyx_pw_9mettagrid_6c_grid_11Environment_5step(PyObject *__pyx_v_self, 
+static PyMethodDef __pyx_mdef_3env_9mettagrid_6c_grid_11Environment_5step = {"step", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_3env_9mettagrid_6c_grid_11Environment_5step, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0};
+static PyObject *__pyx_pw_3env_9mettagrid_6c_grid_11Environment_5step(PyObject *__pyx_v_self, 
 #if CYTHON_METH_FASTCALL
 PyObject *const *__pyx_args, Py_ssize_t __pyx_nargs, PyObject *__pyx_kwds
 #else
@@ -18707,11 +18728,11 @@ PyObject *__pyx_args, PyObject *__pyx_kwds
       __Pyx_Arg_XDECREF_FASTCALL(values[__pyx_temp]);
     }
   }
-  __Pyx_AddTraceback("mettagrid.c_grid.Environment.step", __pyx_clineno, __pyx_lineno, __pyx_filename);
+  __Pyx_AddTraceback("env.mettagrid.c_grid.Environment.step", __pyx_clineno, __pyx_lineno, __pyx_filename);
   __Pyx_RefNannyFinishContext();
   return NULL;
   __pyx_L4_argument_unpacking_done:;
-  __pyx_r = __pyx_pf_9mettagrid_6c_grid_11Environment_4step(((struct __pyx_obj_9mettagrid_6c_grid_Environment *)__pyx_v_self), __pyx_v_np_actions);
+  __pyx_r = __pyx_pf_3env_9mettagrid_6c_grid_11Environment_4step(((struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *)__pyx_v_self), __pyx_v_np_actions);
 
   /* function exit code */
   {
@@ -18724,7 +18745,7 @@ PyObject *__pyx_args, PyObject *__pyx_kwds
   return __pyx_r;
 }
 
-static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_obj_9mettagrid_6c_grid_Environment *__pyx_v_self, PyObject *__pyx_v_np_actions) {
+static PyObject *__pyx_pf_3env_9mettagrid_6c_grid_11Environment_4step(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *__pyx_v_self, PyObject *__pyx_v_np_actions) {
   __Pyx_memviewslice __pyx_v_actions = { 0, 0, { 0 }, { 0 }, { 0 } };
   int __pyx_v_agent_idx;
   int __pyx_v_atn;
@@ -18750,7 +18771,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
   int __pyx_clineno = 0;
   __Pyx_RefNannySetupContext("step", 1);
 
-  /* "mettagrid/c_grid.pyx":84
+  /* "env/mettagrid/c_grid.pyx":84
  * 
  *     def step(self, np_actions):
  *         cdef unsigned int[:] actions = np_actions             # <<<<<<<<<<<<<<
@@ -18762,7 +18783,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
   __pyx_t_1.memview = NULL;
   __pyx_t_1.data = NULL;
 
-  /* "mettagrid/c_grid.pyx":86
+  /* "env/mettagrid/c_grid.pyx":86
  *         cdef unsigned int[:] actions = np_actions
  *         cdef int agent_idx, atn, r, c, dr, dc, dest_r, dest_c
  *         for agent_idx in range(self.num_agents):             # <<<<<<<<<<<<<<
@@ -18774,7 +18795,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
   for (__pyx_t_4 = 0; __pyx_t_4 < __pyx_t_3; __pyx_t_4+=1) {
     __pyx_v_agent_idx = __pyx_t_4;
 
-    /* "mettagrid/c_grid.pyx":87
+    /* "env/mettagrid/c_grid.pyx":87
  *         cdef int agent_idx, atn, r, c, dr, dc, dest_r, dest_c
  *         for agent_idx in range(self.num_agents):
  *             r = self.agent_positions[agent_idx, 0]             # <<<<<<<<<<<<<<
@@ -18785,7 +18806,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
     __pyx_t_6 = 0;
     __pyx_v_r = (*((unsigned int *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->agent_positions.data + __pyx_t_5 * __pyx_v_self->agent_positions.strides[0]) ) + __pyx_t_6 * __pyx_v_self->agent_positions.strides[1]) )));
 
-    /* "mettagrid/c_grid.pyx":88
+    /* "env/mettagrid/c_grid.pyx":88
  *         for agent_idx in range(self.num_agents):
  *             r = self.agent_positions[agent_idx, 0]
  *             c = self.agent_positions[agent_idx, 1]             # <<<<<<<<<<<<<<
@@ -18796,7 +18817,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
     __pyx_t_5 = 1;
     __pyx_v_c = (*((unsigned int *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->agent_positions.data + __pyx_t_6 * __pyx_v_self->agent_positions.strides[0]) ) + __pyx_t_5 * __pyx_v_self->agent_positions.strides[1]) )));
 
-    /* "mettagrid/c_grid.pyx":89
+    /* "env/mettagrid/c_grid.pyx":89
  *             r = self.agent_positions[agent_idx, 0]
  *             c = self.agent_positions[agent_idx, 1]
  *             atn = actions[agent_idx]             # <<<<<<<<<<<<<<
@@ -18806,7 +18827,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
     __pyx_t_5 = __pyx_v_agent_idx;
     __pyx_v_atn = (*((unsigned int *) ( /* dim=0 */ (__pyx_v_actions.data + __pyx_t_5 * __pyx_v_actions.strides[0]) )));
 
-    /* "mettagrid/c_grid.pyx":90
+    /* "env/mettagrid/c_grid.pyx":90
  *             c = self.agent_positions[agent_idx, 1]
  *             atn = actions[agent_idx]
  *             dr = 0             # <<<<<<<<<<<<<<
@@ -18815,7 +18836,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
  */
     __pyx_v_dr = 0;
 
-    /* "mettagrid/c_grid.pyx":91
+    /* "env/mettagrid/c_grid.pyx":91
  *             atn = actions[agent_idx]
  *             dr = 0
  *             dc = 0             # <<<<<<<<<<<<<<
@@ -18824,17 +18845,17 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
  */
     __pyx_v_dc = 0;
 
-    /* "mettagrid/c_grid.pyx":92
+    /* "env/mettagrid/c_grid.pyx":92
  *             dr = 0
  *             dc = 0
  *             if atn == PASS:             # <<<<<<<<<<<<<<
  *                 continue
  *             elif atn == NORTH:
  */
-    __pyx_t_7 = (__pyx_v_atn == __pyx_v_9mettagrid_6c_grid_PASS);
+    __pyx_t_7 = (__pyx_v_atn == __pyx_v_3env_9mettagrid_6c_grid_PASS);
     if (__pyx_t_7) {
 
-      /* "mettagrid/c_grid.pyx":93
+      /* "env/mettagrid/c_grid.pyx":93
  *             dc = 0
  *             if atn == PASS:
  *                 continue             # <<<<<<<<<<<<<<
@@ -18843,7 +18864,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
  */
       goto __pyx_L3_continue;
 
-      /* "mettagrid/c_grid.pyx":92
+      /* "env/mettagrid/c_grid.pyx":92
  *             dr = 0
  *             dc = 0
  *             if atn == PASS:             # <<<<<<<<<<<<<<
@@ -18852,17 +18873,17 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
  */
     }
 
-    /* "mettagrid/c_grid.pyx":94
+    /* "env/mettagrid/c_grid.pyx":94
  *             if atn == PASS:
  *                 continue
  *             elif atn == NORTH:             # <<<<<<<<<<<<<<
  *                 dr = -1
  *             elif atn == SOUTH:
  */
-    __pyx_t_7 = (__pyx_v_atn == __pyx_v_9mettagrid_6c_grid_NORTH);
+    __pyx_t_7 = (__pyx_v_atn == __pyx_v_3env_9mettagrid_6c_grid_NORTH);
     if (__pyx_t_7) {
 
-      /* "mettagrid/c_grid.pyx":95
+      /* "env/mettagrid/c_grid.pyx":95
  *                 continue
  *             elif atn == NORTH:
  *                 dr = -1             # <<<<<<<<<<<<<<
@@ -18871,7 +18892,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
  */
       __pyx_v_dr = -1;
 
-      /* "mettagrid/c_grid.pyx":94
+      /* "env/mettagrid/c_grid.pyx":94
  *             if atn == PASS:
  *                 continue
  *             elif atn == NORTH:             # <<<<<<<<<<<<<<
@@ -18881,17 +18902,17 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
       goto __pyx_L5;
     }
 
-    /* "mettagrid/c_grid.pyx":96
+    /* "env/mettagrid/c_grid.pyx":96
  *             elif atn == NORTH:
  *                 dr = -1
  *             elif atn == SOUTH:             # <<<<<<<<<<<<<<
  *                 dr = 1
  *             elif atn == EAST:
  */
-    __pyx_t_7 = (__pyx_v_atn == __pyx_v_9mettagrid_6c_grid_SOUTH);
+    __pyx_t_7 = (__pyx_v_atn == __pyx_v_3env_9mettagrid_6c_grid_SOUTH);
     if (__pyx_t_7) {
 
-      /* "mettagrid/c_grid.pyx":97
+      /* "env/mettagrid/c_grid.pyx":97
  *                 dr = -1
  *             elif atn == SOUTH:
  *                 dr = 1             # <<<<<<<<<<<<<<
@@ -18900,7 +18921,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
  */
       __pyx_v_dr = 1;
 
-      /* "mettagrid/c_grid.pyx":96
+      /* "env/mettagrid/c_grid.pyx":96
  *             elif atn == NORTH:
  *                 dr = -1
  *             elif atn == SOUTH:             # <<<<<<<<<<<<<<
@@ -18910,17 +18931,17 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
       goto __pyx_L5;
     }
 
-    /* "mettagrid/c_grid.pyx":98
+    /* "env/mettagrid/c_grid.pyx":98
  *             elif atn == SOUTH:
  *                 dr = 1
  *             elif atn == EAST:             # <<<<<<<<<<<<<<
  *                 dc = 1
  *             elif atn == WEST:
  */
-    __pyx_t_7 = (__pyx_v_atn == __pyx_v_9mettagrid_6c_grid_EAST);
+    __pyx_t_7 = (__pyx_v_atn == __pyx_v_3env_9mettagrid_6c_grid_EAST);
     if (__pyx_t_7) {
 
-      /* "mettagrid/c_grid.pyx":99
+      /* "env/mettagrid/c_grid.pyx":99
  *                 dr = 1
  *             elif atn == EAST:
  *                 dc = 1             # <<<<<<<<<<<<<<
@@ -18929,7 +18950,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
  */
       __pyx_v_dc = 1;
 
-      /* "mettagrid/c_grid.pyx":98
+      /* "env/mettagrid/c_grid.pyx":98
  *             elif atn == SOUTH:
  *                 dr = 1
  *             elif atn == EAST:             # <<<<<<<<<<<<<<
@@ -18939,17 +18960,17 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
       goto __pyx_L5;
     }
 
-    /* "mettagrid/c_grid.pyx":100
+    /* "env/mettagrid/c_grid.pyx":100
  *             elif atn == EAST:
  *                 dc = 1
  *             elif atn == WEST:             # <<<<<<<<<<<<<<
  *                 dc = -1
  *             else:
  */
-    __pyx_t_7 = (__pyx_v_atn == __pyx_v_9mettagrid_6c_grid_WEST);
+    __pyx_t_7 = (__pyx_v_atn == __pyx_v_3env_9mettagrid_6c_grid_WEST);
     if (likely(__pyx_t_7)) {
 
-      /* "mettagrid/c_grid.pyx":101
+      /* "env/mettagrid/c_grid.pyx":101
  *                 dc = 1
  *             elif atn == WEST:
  *                 dc = -1             # <<<<<<<<<<<<<<
@@ -18958,7 +18979,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
  */
       __pyx_v_dc = -1;
 
-      /* "mettagrid/c_grid.pyx":100
+      /* "env/mettagrid/c_grid.pyx":100
  *             elif atn == EAST:
  *                 dc = 1
  *             elif atn == WEST:             # <<<<<<<<<<<<<<
@@ -18968,7 +18989,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
       goto __pyx_L5;
     }
 
-    /* "mettagrid/c_grid.pyx":103
+    /* "env/mettagrid/c_grid.pyx":103
  *                 dc = -1
  *             else:
  *                 raise ValueError(f'Invalid action: {atn}')             # <<<<<<<<<<<<<<
@@ -18990,7 +19011,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
     }
     __pyx_L5:;
 
-    /* "mettagrid/c_grid.pyx":105
+    /* "env/mettagrid/c_grid.pyx":105
  *                 raise ValueError(f'Invalid action: {atn}')
  * 
  *             dest_r = r + dr             # <<<<<<<<<<<<<<
@@ -18999,7 +19020,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
  */
     __pyx_v_dest_r = (__pyx_v_r + __pyx_v_dr);
 
-    /* "mettagrid/c_grid.pyx":106
+    /* "env/mettagrid/c_grid.pyx":106
  * 
  *             dest_r = r + dr
  *             dest_c = c + dc             # <<<<<<<<<<<<<<
@@ -19008,7 +19029,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
  */
     __pyx_v_dest_c = (__pyx_v_c + __pyx_v_dc);
 
-    /* "mettagrid/c_grid.pyx":108
+    /* "env/mettagrid/c_grid.pyx":108
  *             dest_c = c + dc
  * 
  *             if self.grid[dest_r, dest_c] == 0:             # <<<<<<<<<<<<<<
@@ -19020,7 +19041,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
     __pyx_t_7 = ((*((unsigned char *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->grid.data + __pyx_t_5 * __pyx_v_self->grid.strides[0]) ) + __pyx_t_6 * __pyx_v_self->grid.strides[1]) ))) == 0);
     if (__pyx_t_7) {
 
-      /* "mettagrid/c_grid.pyx":109
+      /* "env/mettagrid/c_grid.pyx":109
  * 
  *             if self.grid[dest_r, dest_c] == 0:
  *                 self.grid[r, c] = EMPTY             # <<<<<<<<<<<<<<
@@ -19029,9 +19050,9 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
  */
       __pyx_t_6 = __pyx_v_r;
       __pyx_t_5 = __pyx_v_c;
-      *((unsigned char *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->grid.data + __pyx_t_6 * __pyx_v_self->grid.strides[0]) ) + __pyx_t_5 * __pyx_v_self->grid.strides[1]) )) = __pyx_v_9mettagrid_6c_grid_EMPTY;
+      *((unsigned char *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->grid.data + __pyx_t_6 * __pyx_v_self->grid.strides[0]) ) + __pyx_t_5 * __pyx_v_self->grid.strides[1]) )) = __pyx_v_3env_9mettagrid_6c_grid_EMPTY;
 
-      /* "mettagrid/c_grid.pyx":110
+      /* "env/mettagrid/c_grid.pyx":110
  *             if self.grid[dest_r, dest_c] == 0:
  *                 self.grid[r, c] = EMPTY
  *                 self.grid[dest_r, dest_c] = AGENT             # <<<<<<<<<<<<<<
@@ -19040,9 +19061,9 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
  */
       __pyx_t_5 = __pyx_v_dest_r;
       __pyx_t_6 = __pyx_v_dest_c;
-      *((unsigned char *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->grid.data + __pyx_t_5 * __pyx_v_self->grid.strides[0]) ) + __pyx_t_6 * __pyx_v_self->grid.strides[1]) )) = __pyx_v_9mettagrid_6c_grid_AGENT;
+      *((unsigned char *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->grid.data + __pyx_t_5 * __pyx_v_self->grid.strides[0]) ) + __pyx_t_6 * __pyx_v_self->grid.strides[1]) )) = __pyx_v_3env_9mettagrid_6c_grid_AGENT;
 
-      /* "mettagrid/c_grid.pyx":111
+      /* "env/mettagrid/c_grid.pyx":111
  *                 self.grid[r, c] = EMPTY
  *                 self.grid[dest_r, dest_c] = AGENT
  *                 self.agent_positions[agent_idx, 0] = dest_r             # <<<<<<<<<<<<<<
@@ -19053,7 +19074,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
       __pyx_t_5 = 0;
       *((unsigned int *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->agent_positions.data + __pyx_t_6 * __pyx_v_self->agent_positions.strides[0]) ) + __pyx_t_5 * __pyx_v_self->agent_positions.strides[1]) )) = __pyx_v_dest_r;
 
-      /* "mettagrid/c_grid.pyx":112
+      /* "env/mettagrid/c_grid.pyx":112
  *                 self.grid[dest_r, dest_c] = AGENT
  *                 self.agent_positions[agent_idx, 0] = dest_r
  *                 self.agent_positions[agent_idx, 1] = dest_c             # <<<<<<<<<<<<<<
@@ -19064,7 +19085,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
       __pyx_t_6 = 1;
       *((unsigned int *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self->agent_positions.data + __pyx_t_5 * __pyx_v_self->agent_positions.strides[0]) ) + __pyx_t_6 * __pyx_v_self->agent_positions.strides[1]) )) = __pyx_v_dest_c;
 
-      /* "mettagrid/c_grid.pyx":108
+      /* "env/mettagrid/c_grid.pyx":108
  *             dest_c = c + dc
  * 
  *             if self.grid[dest_r, dest_c] == 0:             # <<<<<<<<<<<<<<
@@ -19075,14 +19096,14 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
     __pyx_L3_continue:;
   }
 
-  /* "mettagrid/c_grid.pyx":114
+  /* "env/mettagrid/c_grid.pyx":114
  *                 self.agent_positions[agent_idx, 1] = dest_c
  * 
  *         self._compute_observations()             # <<<<<<<<<<<<<<
  */
-  ((struct __pyx_vtabstruct_9mettagrid_6c_grid_Environment *)__pyx_v_self->__pyx_vtab)->_compute_observations(__pyx_v_self); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 114, __pyx_L1_error)
+  ((struct __pyx_vtabstruct_3env_9mettagrid_6c_grid_Environment *)__pyx_v_self->__pyx_vtab)->_compute_observations(__pyx_v_self); if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 114, __pyx_L1_error)
 
-  /* "mettagrid/c_grid.pyx":83
+  /* "env/mettagrid/c_grid.pyx":83
  *         self._compute_observations()
  * 
  *     def step(self, np_actions):             # <<<<<<<<<<<<<<
@@ -19097,7 +19118,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
   __PYX_XCLEAR_MEMVIEW(&__pyx_t_1, 1);
   __Pyx_XDECREF(__pyx_t_8);
   __Pyx_XDECREF(__pyx_t_9);
-  __Pyx_AddTraceback("mettagrid.c_grid.Environment.step", __pyx_clineno, __pyx_lineno, __pyx_filename);
+  __Pyx_AddTraceback("env.mettagrid.c_grid.Environment.step", __pyx_clineno, __pyx_lineno, __pyx_filename);
   __pyx_r = NULL;
   __pyx_L0:;
   __PYX_XCLEAR_MEMVIEW(&__pyx_v_actions, 1);
@@ -19113,15 +19134,15 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
  */
 
 /* Python wrapper */
-static PyObject *__pyx_pw_9mettagrid_6c_grid_11Environment_7__reduce_cython__(PyObject *__pyx_v_self, 
+static PyObject *__pyx_pw_3env_9mettagrid_6c_grid_11Environment_7__reduce_cython__(PyObject *__pyx_v_self, 
 #if CYTHON_METH_FASTCALL
 PyObject *const *__pyx_args, Py_ssize_t __pyx_nargs, PyObject *__pyx_kwds
 #else
 PyObject *__pyx_args, PyObject *__pyx_kwds
 #endif
 ); /*proto*/
-static PyMethodDef __pyx_mdef_9mettagrid_6c_grid_11Environment_7__reduce_cython__ = {"__reduce_cython__", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_9mettagrid_6c_grid_11Environment_7__reduce_cython__, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0};
-static PyObject *__pyx_pw_9mettagrid_6c_grid_11Environment_7__reduce_cython__(PyObject *__pyx_v_self, 
+static PyMethodDef __pyx_mdef_3env_9mettagrid_6c_grid_11Environment_7__reduce_cython__ = {"__reduce_cython__", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_3env_9mettagrid_6c_grid_11Environment_7__reduce_cython__, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0};
+static PyObject *__pyx_pw_3env_9mettagrid_6c_grid_11Environment_7__reduce_cython__(PyObject *__pyx_v_self, 
 #if CYTHON_METH_FASTCALL
 PyObject *const *__pyx_args, Py_ssize_t __pyx_nargs, PyObject *__pyx_kwds
 #else
@@ -19146,14 +19167,14 @@ PyObject *__pyx_args, PyObject *__pyx_kwds
   if (unlikely(__pyx_nargs > 0)) {
     __Pyx_RaiseArgtupleInvalid("__reduce_cython__", 1, 0, 0, __pyx_nargs); return NULL;}
   if (unlikely(__pyx_kwds) && __Pyx_NumKwargs_FASTCALL(__pyx_kwds) && unlikely(!__Pyx_CheckKeywordStrings(__pyx_kwds, "__reduce_cython__", 0))) return NULL;
-  __pyx_r = __pyx_pf_9mettagrid_6c_grid_11Environment_6__reduce_cython__(((struct __pyx_obj_9mettagrid_6c_grid_Environment *)__pyx_v_self));
+  __pyx_r = __pyx_pf_3env_9mettagrid_6c_grid_11Environment_6__reduce_cython__(((struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *)__pyx_v_self));
 
   /* function exit code */
   __Pyx_RefNannyFinishContext();
   return __pyx_r;
 }
 
-static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_6__reduce_cython__(struct __pyx_obj_9mettagrid_6c_grid_Environment *__pyx_v_self) {
+static PyObject *__pyx_pf_3env_9mettagrid_6c_grid_11Environment_6__reduce_cython__(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *__pyx_v_self) {
   PyObject *__pyx_v_state = 0;
   PyObject *__pyx_v__dict = 0;
   int __pyx_v_use_setstate;
@@ -19410,7 +19431,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_6__reduce_cython__(st
   __Pyx_XDECREF(__pyx_t_8);
   __Pyx_XDECREF(__pyx_t_9);
   __Pyx_XDECREF(__pyx_t_10);
-  __Pyx_AddTraceback("mettagrid.c_grid.Environment.__reduce_cython__", __pyx_clineno, __pyx_lineno, __pyx_filename);
+  __Pyx_AddTraceback("env.mettagrid.c_grid.Environment.__reduce_cython__", __pyx_clineno, __pyx_lineno, __pyx_filename);
   __pyx_r = NULL;
   __pyx_L0:;
   __Pyx_XDECREF(__pyx_v_state);
@@ -19428,15 +19449,15 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_6__reduce_cython__(st
  */
 
 /* Python wrapper */
-static PyObject *__pyx_pw_9mettagrid_6c_grid_11Environment_9__setstate_cython__(PyObject *__pyx_v_self, 
+static PyObject *__pyx_pw_3env_9mettagrid_6c_grid_11Environment_9__setstate_cython__(PyObject *__pyx_v_self, 
 #if CYTHON_METH_FASTCALL
 PyObject *const *__pyx_args, Py_ssize_t __pyx_nargs, PyObject *__pyx_kwds
 #else
 PyObject *__pyx_args, PyObject *__pyx_kwds
 #endif
 ); /*proto*/
-static PyMethodDef __pyx_mdef_9mettagrid_6c_grid_11Environment_9__setstate_cython__ = {"__setstate_cython__", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_9mettagrid_6c_grid_11Environment_9__setstate_cython__, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0};
-static PyObject *__pyx_pw_9mettagrid_6c_grid_11Environment_9__setstate_cython__(PyObject *__pyx_v_self, 
+static PyMethodDef __pyx_mdef_3env_9mettagrid_6c_grid_11Environment_9__setstate_cython__ = {"__setstate_cython__", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_3env_9mettagrid_6c_grid_11Environment_9__setstate_cython__, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0};
+static PyObject *__pyx_pw_3env_9mettagrid_6c_grid_11Environment_9__setstate_cython__(PyObject *__pyx_v_self, 
 #if CYTHON_METH_FASTCALL
 PyObject *const *__pyx_args, Py_ssize_t __pyx_nargs, PyObject *__pyx_kwds
 #else
@@ -19506,11 +19527,11 @@ PyObject *__pyx_args, PyObject *__pyx_kwds
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-  __Pyx_AddTraceback("mettagrid.c_grid.Environment.__setstate_cython__", __pyx_clineno, __pyx_lineno, __pyx_filename);
+  __Pyx_AddTraceback("env.mettagrid.c_grid.Environment.__setstate_cython__", __pyx_clineno, __pyx_lineno, __pyx_filename);
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+  __pyx_r = __pyx_pf_3env_9mettagrid_6c_grid_11Environment_8__setstate_cython__(((struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *)__pyx_v_self), __pyx_v___pyx_state);
 
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+static PyObject *__pyx_pf_3env_9mettagrid_6c_grid_11Environment_8__setstate_cython__(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *__pyx_v_self, PyObject *__pyx_v___pyx_state) {
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+  __pyx_t_1 = __pyx_f_3env_9mettagrid_6c_grid___pyx_unpickle_Environment__set_state(__pyx_v_self, ((PyObject*)__pyx_v___pyx_state)); if (unlikely(!__pyx_t_1)) __PYX_ERR(1, 17, __pyx_L1_error)
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@@ -19554,7 +19575,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_8__setstate_cython__(
   goto __pyx_L0;
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-  __Pyx_AddTraceback("mettagrid.c_grid.Environment.__setstate_cython__", __pyx_clineno, __pyx_lineno, __pyx_filename);
+  __Pyx_AddTraceback("env.mettagrid.c_grid.Environment.__setstate_cython__", __pyx_clineno, __pyx_lineno, __pyx_filename);
   __pyx_r = NULL;
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   __Pyx_XGIVEREF(__pyx_r);
@@ -19569,15 +19590,15 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_8__setstate_cython__(
  */
 
 /* Python wrapper */
-static PyObject *__pyx_pw_9mettagrid_6c_grid_1__pyx_unpickle_Environment(PyObject *__pyx_self, 
+static PyObject *__pyx_pw_3env_9mettagrid_6c_grid_1__pyx_unpickle_Environment(PyObject *__pyx_self, 
 #if CYTHON_METH_FASTCALL
 PyObject *const *__pyx_args, Py_ssize_t __pyx_nargs, PyObject *__pyx_kwds
 #else
 PyObject *__pyx_args, PyObject *__pyx_kwds
 #endif
 ); /*proto*/
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-static PyObject *__pyx_pw_9mettagrid_6c_grid_1__pyx_unpickle_Environment(PyObject *__pyx_self, 
+static PyMethodDef __pyx_mdef_3env_9mettagrid_6c_grid_1__pyx_unpickle_Environment = {"__pyx_unpickle_Environment", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_3env_9mettagrid_6c_grid_1__pyx_unpickle_Environment, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0};
+static PyObject *__pyx_pw_3env_9mettagrid_6c_grid_1__pyx_unpickle_Environment(PyObject *__pyx_self, 
 #if CYTHON_METH_FASTCALL
 PyObject *const *__pyx_args, Py_ssize_t __pyx_nargs, PyObject *__pyx_kwds
 #else
@@ -19677,11 +19698,11 @@ PyObject *__pyx_args, PyObject *__pyx_kwds
       __Pyx_Arg_XDECREF_FASTCALL(values[__pyx_temp]);
     }
   }
-  __Pyx_AddTraceback("mettagrid.c_grid.__pyx_unpickle_Environment", __pyx_clineno, __pyx_lineno, __pyx_filename);
+  __Pyx_AddTraceback("env.mettagrid.c_grid.__pyx_unpickle_Environment", __pyx_clineno, __pyx_lineno, __pyx_filename);
   __Pyx_RefNannyFinishContext();
   return NULL;
   __pyx_L4_argument_unpacking_done:;
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+  __pyx_r = __pyx_pf_3env_9mettagrid_6c_grid___pyx_unpickle_Environment(__pyx_self, __pyx_v___pyx_type, __pyx_v___pyx_checksum, __pyx_v___pyx_state);
 
   /* function exit code */
   {
@@ -19694,7 +19715,7 @@ PyObject *__pyx_args, PyObject *__pyx_kwds
   return __pyx_r;
 }
 
-static PyObject *__pyx_pf_9mettagrid_6c_grid___pyx_unpickle_Environment(CYTHON_UNUSED PyObject *__pyx_self, PyObject *__pyx_v___pyx_type, long __pyx_v___pyx_checksum, PyObject *__pyx_v___pyx_state) {
+static PyObject *__pyx_pf_3env_9mettagrid_6c_grid___pyx_unpickle_Environment(CYTHON_UNUSED PyObject *__pyx_self, PyObject *__pyx_v___pyx_type, long __pyx_v___pyx_checksum, PyObject *__pyx_v___pyx_state) {
   PyObject *__pyx_v___pyx_PickleError = 0;
   PyObject *__pyx_v___pyx_result = 0;
   PyObject *__pyx_r = NULL;
@@ -19776,7 +19797,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid___pyx_unpickle_Environment(CYTHON_U
  *     if __pyx_state is not None:
  *         __pyx_unpickle_Environment__set_state(<Environment> __pyx_result, __pyx_state)
  */
-  __pyx_t_3 = __Pyx_PyObject_GetAttrStr(((PyObject *)__pyx_ptype_9mettagrid_6c_grid_Environment), __pyx_n_s_new); if (unlikely(!__pyx_t_3)) __PYX_ERR(1, 7, __pyx_L1_error)
+  __pyx_t_3 = __Pyx_PyObject_GetAttrStr(((PyObject *)__pyx_ptype_3env_9mettagrid_6c_grid_Environment), __pyx_n_s_new); if (unlikely(!__pyx_t_3)) __PYX_ERR(1, 7, __pyx_L1_error)
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   __pyx_t_4 = NULL;
   __pyx_t_5 = 0;
@@ -19821,7 +19842,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid___pyx_unpickle_Environment(CYTHON_U
  * cdef __pyx_unpickle_Environment__set_state(Environment __pyx_result, tuple __pyx_state):
  */
     if (!(likely(PyTuple_CheckExact(__pyx_v___pyx_state))||((__pyx_v___pyx_state) == Py_None) || __Pyx_RaiseUnexpectedTypeError("tuple", __pyx_v___pyx_state))) __PYX_ERR(1, 9, __pyx_L1_error)
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+    __pyx_t_1 = __pyx_f_3env_9mettagrid_6c_grid___pyx_unpickle_Environment__set_state(((struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *)__pyx_v___pyx_result), ((PyObject*)__pyx_v___pyx_state)); if (unlikely(!__pyx_t_1)) __PYX_ERR(1, 9, __pyx_L1_error)
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@@ -19857,7 +19878,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid___pyx_unpickle_Environment(CYTHON_U
   __Pyx_XDECREF(__pyx_t_1);
   __Pyx_XDECREF(__pyx_t_3);
   __Pyx_XDECREF(__pyx_t_4);
-  __Pyx_AddTraceback("mettagrid.c_grid.__pyx_unpickle_Environment", __pyx_clineno, __pyx_lineno, __pyx_filename);
+  __Pyx_AddTraceback("env.mettagrid.c_grid.__pyx_unpickle_Environment", __pyx_clineno, __pyx_lineno, __pyx_filename);
   __pyx_r = NULL;
   __pyx_L0:;
   __Pyx_XDECREF(__pyx_v___pyx_PickleError);
@@ -19875,7 +19896,7 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid___pyx_unpickle_Environment(CYTHON_U
  *     if len(__pyx_state) > 9 and hasattr(__pyx_result, '__dict__'):
  */
 
-static PyObject *__pyx_f_9mettagrid_6c_grid___pyx_unpickle_Environment__set_state(struct __pyx_obj_9mettagrid_6c_grid_Environment *__pyx_v___pyx_result, PyObject *__pyx_v___pyx_state) {
+static PyObject *__pyx_f_3env_9mettagrid_6c_grid___pyx_unpickle_Environment__set_state(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *__pyx_v___pyx_result, PyObject *__pyx_v___pyx_state) {
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   __Pyx_memviewslice __pyx_t_1 = { 0, 0, { 0 }, { 0 }, { 0 } };
@@ -20053,17 +20074,17 @@ static PyObject *__pyx_f_9mettagrid_6c_grid___pyx_unpickle_Environment__set_stat
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   __Pyx_XDECREF(__pyx_t_9);
   __Pyx_XDECREF(__pyx_t_10);
-  __Pyx_AddTraceback("mettagrid.c_grid.__pyx_unpickle_Environment__set_state", __pyx_clineno, __pyx_lineno, __pyx_filename);
+  __Pyx_AddTraceback("env.mettagrid.c_grid.__pyx_unpickle_Environment__set_state", __pyx_clineno, __pyx_lineno, __pyx_filename);
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   __pyx_L0:;
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   return __pyx_r;
 }
-static struct __pyx_vtabstruct_9mettagrid_6c_grid_Environment __pyx_vtable_9mettagrid_6c_grid_Environment;
+static struct __pyx_vtabstruct_3env_9mettagrid_6c_grid_Environment __pyx_vtable_3env_9mettagrid_6c_grid_Environment;
 
-static PyObject *__pyx_tp_new_9mettagrid_6c_grid_Environment(PyTypeObject *t, CYTHON_UNUSED PyObject *a, CYTHON_UNUSED PyObject *k) {
-  struct __pyx_obj_9mettagrid_6c_grid_Environment *p;
+static PyObject *__pyx_tp_new_3env_9mettagrid_6c_grid_Environment(PyTypeObject *t, CYTHON_UNUSED PyObject *a, CYTHON_UNUSED PyObject *k) {
+  struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *p;
   PyObject *o;
   #if CYTHON_COMPILING_IN_LIMITED_API
   allocfunc alloc_func = (allocfunc)PyType_GetSlot(t, Py_tp_alloc);
@@ -20076,8 +20097,8 @@ static PyObject *__pyx_tp_new_9mettagrid_6c_grid_Environment(PyTypeObject *t, CY
   }
   if (unlikely(!o)) return 0;
   #endif
-  p = ((struct __pyx_obj_9mettagrid_6c_grid_Environment *)o);
-  p->__pyx_vtab = __pyx_vtabptr_9mettagrid_6c_grid_Environment;
+  p = ((struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *)o);
+  p->__pyx_vtab = __pyx_vtabptr_3env_9mettagrid_6c_grid_Environment;
   p->grid.data = NULL;
   p->grid.memview = NULL;
   p->observations.data = NULL;
@@ -20089,11 +20110,11 @@ static PyObject *__pyx_tp_new_9mettagrid_6c_grid_Environment(PyTypeObject *t, CY
   return o;
 }
 
-static void __pyx_tp_dealloc_9mettagrid_6c_grid_Environment(PyObject *o) {
-  struct __pyx_obj_9mettagrid_6c_grid_Environment *p = (struct __pyx_obj_9mettagrid_6c_grid_Environment *)o;
+static void __pyx_tp_dealloc_3env_9mettagrid_6c_grid_Environment(PyObject *o) {
+  struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *p = (struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *)o;
   #if CYTHON_USE_TP_FINALIZE
   if (unlikely((PY_VERSION_HEX >= 0x03080000 || __Pyx_PyType_HasFeature(Py_TYPE(o), Py_TPFLAGS_HAVE_FINALIZE)) && __Pyx_PyObject_GetSlot(o, tp_finalize, destructor)) && (!PyType_IS_GC(Py_TYPE(o)) || !__Pyx_PyObject_GC_IsFinalized(o))) {
-    if (__Pyx_PyObject_GetSlot(o, tp_dealloc, destructor) == __pyx_tp_dealloc_9mettagrid_6c_grid_Environment) {
+    if (__Pyx_PyObject_GetSlot(o, tp_dealloc, destructor) == __pyx_tp_dealloc_3env_9mettagrid_6c_grid_Environment) {
       if (PyObject_CallFinalizerFromDealloc(o)) return;
     }
   }
@@ -20116,36 +20137,36 @@ static void __pyx_tp_dealloc_9mettagrid_6c_grid_Environment(PyObject *o) {
   #endif
 }
 
-static PyMethodDef __pyx_methods_9mettagrid_6c_grid_Environment[] = {
-  {"reset", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_9mettagrid_6c_grid_11Environment_3reset, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0},
-  {"step", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_9mettagrid_6c_grid_11Environment_5step, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0},
-  {"__reduce_cython__", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_9mettagrid_6c_grid_11Environment_7__reduce_cython__, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0},
-  {"__setstate_cython__", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_9mettagrid_6c_grid_11Environment_9__setstate_cython__, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0},
+static PyMethodDef __pyx_methods_3env_9mettagrid_6c_grid_Environment[] = {
+  {"reset", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_3env_9mettagrid_6c_grid_11Environment_3reset, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0},
+  {"step", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_3env_9mettagrid_6c_grid_11Environment_5step, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0},
+  {"__reduce_cython__", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_3env_9mettagrid_6c_grid_11Environment_7__reduce_cython__, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0},
+  {"__setstate_cython__", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_3env_9mettagrid_6c_grid_11Environment_9__setstate_cython__, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0},
   {0, 0, 0, 0}
 };
 #if CYTHON_USE_TYPE_SPECS
-static PyType_Slot __pyx_type_9mettagrid_6c_grid_Environment_slots[] = {
-  {Py_tp_dealloc, (void *)__pyx_tp_dealloc_9mettagrid_6c_grid_Environment},
-  {Py_tp_methods, (void *)__pyx_methods_9mettagrid_6c_grid_Environment},
-  {Py_tp_init, (void *)__pyx_pw_9mettagrid_6c_grid_11Environment_1__init__},
-  {Py_tp_new, (void *)__pyx_tp_new_9mettagrid_6c_grid_Environment},
+static PyType_Slot __pyx_type_3env_9mettagrid_6c_grid_Environment_slots[] = {
+  {Py_tp_dealloc, (void *)__pyx_tp_dealloc_3env_9mettagrid_6c_grid_Environment},
+  {Py_tp_methods, (void *)__pyx_methods_3env_9mettagrid_6c_grid_Environment},
+  {Py_tp_init, (void *)__pyx_pw_3env_9mettagrid_6c_grid_11Environment_1__init__},
+  {Py_tp_new, (void *)__pyx_tp_new_3env_9mettagrid_6c_grid_Environment},
   {0, 0},
 };
-static PyType_Spec __pyx_type_9mettagrid_6c_grid_Environment_spec = {
-  "mettagrid.c_grid.Environment",
-  sizeof(struct __pyx_obj_9mettagrid_6c_grid_Environment),
+static PyType_Spec __pyx_type_3env_9mettagrid_6c_grid_Environment_spec = {
+  "env.mettagrid.c_grid.Environment",
+  sizeof(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment),
   0,
   Py_TPFLAGS_DEFAULT|Py_TPFLAGS_HAVE_VERSION_TAG|Py_TPFLAGS_CHECKTYPES|Py_TPFLAGS_HAVE_NEWBUFFER|Py_TPFLAGS_BASETYPE,
-  __pyx_type_9mettagrid_6c_grid_Environment_slots,
+  __pyx_type_3env_9mettagrid_6c_grid_Environment_slots,
 };
 #else
 
-static PyTypeObject __pyx_type_9mettagrid_6c_grid_Environment = {
+static PyTypeObject __pyx_type_3env_9mettagrid_6c_grid_Environment = {
   PyVarObject_HEAD_INIT(0, 0)
-  "mettagrid.c_grid.""Environment", /*tp_name*/
-  sizeof(struct __pyx_obj_9mettagrid_6c_grid_Environment), /*tp_basicsize*/
+  "env.mettagrid.c_grid.""Environment", /*tp_name*/
+  sizeof(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment), /*tp_basicsize*/
   0, /*tp_itemsize*/
-  __pyx_tp_dealloc_9mettagrid_6c_grid_Environment, /*tp_dealloc*/
+  __pyx_tp_dealloc_3env_9mettagrid_6c_grid_Environment, /*tp_dealloc*/
   #if PY_VERSION_HEX < 0x030800b4
   0, /*tp_print*/
   #endif
@@ -20178,7 +20199,7 @@ static PyTypeObject __pyx_type_9mettagrid_6c_grid_Environment = {
   0, /*tp_weaklistoffset*/
   0, /*tp_iter*/
   0, /*tp_iternext*/
-  __pyx_methods_9mettagrid_6c_grid_Environment, /*tp_methods*/
+  __pyx_methods_3env_9mettagrid_6c_grid_Environment, /*tp_methods*/
   0, /*tp_members*/
   0, /*tp_getset*/
   0, /*tp_base*/
@@ -20188,9 +20209,9 @@ static PyTypeObject __pyx_type_9mettagrid_6c_grid_Environment = {
   #if !CYTHON_USE_TYPE_SPECS
   0, /*tp_dictoffset*/
   #endif
-  __pyx_pw_9mettagrid_6c_grid_11Environment_1__init__, /*tp_init*/
+  __pyx_pw_3env_9mettagrid_6c_grid_11Environment_1__init__, /*tp_init*/
   0, /*tp_alloc*/
-  __pyx_tp_new_9mettagrid_6c_grid_Environment, /*tp_new*/
+  __pyx_tp_new_3env_9mettagrid_6c_grid_Environment, /*tp_new*/
   0, /*tp_free*/
   0, /*tp_is_gc*/
   0, /*tp_bases*/
@@ -20359,7 +20380,7 @@ static PyType_Slot __pyx_type___pyx_array_slots[] = {
   {0, 0},
 };
 static PyType_Spec __pyx_type___pyx_array_spec = {
-  "mettagrid.c_grid.array",
+  "env.mettagrid.c_grid.array",
   sizeof(struct __pyx_array_obj),
   0,
   Py_TPFLAGS_DEFAULT|Py_TPFLAGS_HAVE_VERSION_TAG|Py_TPFLAGS_CHECKTYPES|Py_TPFLAGS_HAVE_NEWBUFFER|Py_TPFLAGS_BASETYPE|Py_TPFLAGS_SEQUENCE,
@@ -20405,7 +20426,7 @@ static PyBufferProcs __pyx_tp_as_buffer_array = {
 
 static PyTypeObject __pyx_type___pyx_array = {
   PyVarObject_HEAD_INIT(0, 0)
-  "mettagrid.c_grid.""array", /*tp_name*/
+  "env.mettagrid.c_grid.""array", /*tp_name*/
   sizeof(struct __pyx_array_obj), /*tp_basicsize*/
   0, /*tp_itemsize*/
   __pyx_tp_dealloc_array, /*tp_dealloc*/
@@ -20565,7 +20586,7 @@ static PyType_Slot __pyx_type___pyx_MemviewEnum_slots[] = {
   {0, 0},
 };
 static PyType_Spec __pyx_type___pyx_MemviewEnum_spec = {
-  "mettagrid.c_grid.Enum",
+  "env.mettagrid.c_grid.Enum",
   sizeof(struct __pyx_MemviewEnum_obj),
   0,
   Py_TPFLAGS_DEFAULT|Py_TPFLAGS_HAVE_VERSION_TAG|Py_TPFLAGS_CHECKTYPES|Py_TPFLAGS_HAVE_NEWBUFFER|Py_TPFLAGS_BASETYPE|Py_TPFLAGS_HAVE_GC,
@@ -20575,7 +20596,7 @@ static PyType_Spec __pyx_type___pyx_MemviewEnum_spec = {
 
 static PyTypeObject __pyx_type___pyx_MemviewEnum = {
   PyVarObject_HEAD_INIT(0, 0)
-  "mettagrid.c_grid.""Enum", /*tp_name*/
+  "env.mettagrid.c_grid.""Enum", /*tp_name*/
   sizeof(struct __pyx_MemviewEnum_obj), /*tp_basicsize*/
   0, /*tp_itemsize*/
   __pyx_tp_dealloc_Enum, /*tp_dealloc*/
@@ -20872,7 +20893,7 @@ static PyType_Slot __pyx_type___pyx_memoryview_slots[] = {
   {0, 0},
 };
 static PyType_Spec __pyx_type___pyx_memoryview_spec = {
-  "mettagrid.c_grid.memoryview",
+  "env.mettagrid.c_grid.memoryview",
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+static PyObject *__pyx_pf_3env_9mettagrid_6c_grid_11Environment_2reset(struct __pyx_obj_3env_9mettagrid_6c_grid_Environment *__pyx_v_self, PyObject *__pyx_v_observations, CYTHON_UNUSED PyObject *__pyx_v_seed) {
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-  <span class='pyx_c_api'>__Pyx_AddTraceback</span>("mettagrid.c_grid.Environment.reset", __pyx_clineno, __pyx_lineno, __pyx_filename);
+  <span class='pyx_c_api'>__Pyx_AddTraceback</span>("env.mettagrid.c_grid.Environment.reset", __pyx_clineno, __pyx_lineno, __pyx_filename);
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 {
-      unsigned char __pyx_temp_scalar = __pyx_v_9mettagrid_6c_grid_WALL;
+      unsigned char __pyx_temp_scalar = __pyx_v_3env_9mettagrid_6c_grid_WALL;
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 {
-      unsigned char __pyx_temp_scalar = __pyx_v_9mettagrid_6c_grid_WALL;
+      unsigned char __pyx_temp_scalar = __pyx_v_3env_9mettagrid_6c_grid_WALL;
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 {
-      unsigned char __pyx_temp_scalar = __pyx_v_9mettagrid_6c_grid_WALL;
+      unsigned char __pyx_temp_scalar = __pyx_v_3env_9mettagrid_6c_grid_WALL;
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-      unsigned char __pyx_temp_scalar = __pyx_v_9mettagrid_6c_grid_WALL;
+      unsigned char __pyx_temp_scalar = __pyx_v_3env_9mettagrid_6c_grid_WALL;
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 <pre class='cython code score-55 '>/* Python wrapper */
-static PyObject *__pyx_pw_9mettagrid_6c_grid_11Environment_5step(PyObject *__pyx_v_self, 
+static PyObject *__pyx_pw_3env_9mettagrid_6c_grid_11Environment_5step(PyObject *__pyx_v_self, 
 #if CYTHON_METH_FASTCALL
 PyObject *const *__pyx_args, Py_ssize_t __pyx_nargs, PyObject *__pyx_kwds
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 PyObject *__pyx_args, PyObject *__pyx_kwds
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-static PyObject *__pyx_pw_9mettagrid_6c_grid_11Environment_5step(PyObject *__pyx_v_self, 
+static PyMethodDef __pyx_mdef_3env_9mettagrid_6c_grid_11Environment_5step = {"step", (PyCFunction)(void*)(__Pyx_PyCFunction_FastCallWithKeywords)__pyx_pw_3env_9mettagrid_6c_grid_11Environment_5step, __Pyx_METH_FASTCALL|METH_KEYWORDS, 0};
+static PyObject *__pyx_pw_3env_9mettagrid_6c_grid_11Environment_5step(PyObject *__pyx_v_self, 
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 PyObject *const *__pyx_args, Py_ssize_t __pyx_nargs, PyObject *__pyx_kwds
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 </pre><pre class="cython line score-0" onclick="(function(s){s.display=s.display==='block'?'none':'block'})(this.nextElementSibling.style)">+<span class="">099</span>:                 <span class="n">dc</span> <span class="o">=</span> <span class="mf">1</span></pre>
 <pre class='cython code score-0 '>      __pyx_v_dc = 1;
 </pre><pre class="cython line score-0" onclick="(function(s){s.display=s.display==='block'?'none':'block'})(this.nextElementSibling.style)">+<span class="">100</span>:             <span class="k">elif</span> <span class="n">atn</span> <span class="o">==</span> <span class="n">WEST</span><span class="p">:</span></pre>
-<pre class='cython code score-0 '>    __pyx_t_7 = (__pyx_v_atn == __pyx_v_9mettagrid_6c_grid_WEST);
+<pre class='cython code score-0 '>    __pyx_t_7 = (__pyx_v_atn == __pyx_v_3env_9mettagrid_6c_grid_WEST);
     if (likely(__pyx_t_7)) {
 /* … */
       goto __pyx_L5;
@@ -1413,11 +1412,11 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
 </pre><pre class="cython line score-0" onclick="(function(s){s.display=s.display==='block'?'none':'block'})(this.nextElementSibling.style)">+<span class="">109</span>:                 <span class="bp">self</span><span class="o">.</span><span class="n">grid</span><span class="p">[</span><span class="n">r</span><span class="p">,</span> <span class="n">c</span><span class="p">]</span> <span class="o">=</span> <span class="n">EMPTY</span></pre>
 <pre class='cython code score-0 '>      __pyx_t_6 = __pyx_v_r;
       __pyx_t_5 = __pyx_v_c;
-      *((unsigned char *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self-&gt;grid.data + __pyx_t_6 * __pyx_v_self-&gt;grid.strides[0]) ) + __pyx_t_5 * __pyx_v_self-&gt;grid.strides[1]) )) = __pyx_v_9mettagrid_6c_grid_EMPTY;
+      *((unsigned char *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self-&gt;grid.data + __pyx_t_6 * __pyx_v_self-&gt;grid.strides[0]) ) + __pyx_t_5 * __pyx_v_self-&gt;grid.strides[1]) )) = __pyx_v_3env_9mettagrid_6c_grid_EMPTY;
 </pre><pre class="cython line score-0" onclick="(function(s){s.display=s.display==='block'?'none':'block'})(this.nextElementSibling.style)">+<span class="">110</span>:                 <span class="bp">self</span><span class="o">.</span><span class="n">grid</span><span class="p">[</span><span class="n">dest_r</span><span class="p">,</span> <span class="n">dest_c</span><span class="p">]</span> <span class="o">=</span> <span class="n">AGENT</span></pre>
 <pre class='cython code score-0 '>      __pyx_t_5 = __pyx_v_dest_r;
       __pyx_t_6 = __pyx_v_dest_c;
-      *((unsigned char *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self-&gt;grid.data + __pyx_t_5 * __pyx_v_self-&gt;grid.strides[0]) ) + __pyx_t_6 * __pyx_v_self-&gt;grid.strides[1]) )) = __pyx_v_9mettagrid_6c_grid_AGENT;
+      *((unsigned char *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self-&gt;grid.data + __pyx_t_5 * __pyx_v_self-&gt;grid.strides[0]) ) + __pyx_t_6 * __pyx_v_self-&gt;grid.strides[1]) )) = __pyx_v_3env_9mettagrid_6c_grid_AGENT;
 </pre><pre class="cython line score-0" onclick="(function(s){s.display=s.display==='block'?'none':'block'})(this.nextElementSibling.style)">+<span class="">111</span>:                 <span class="bp">self</span><span class="o">.</span><span class="n">agent_positions</span><span class="p">[</span><span class="n">agent_idx</span><span class="p">,</span> <span class="mf">0</span><span class="p">]</span> <span class="o">=</span> <span class="n">dest_r</span></pre>
 <pre class='cython code score-0 '>      __pyx_t_6 = __pyx_v_agent_idx;
       __pyx_t_5 = 0;
@@ -1428,5 +1427,5 @@ static PyObject *__pyx_pf_9mettagrid_6c_grid_11Environment_4step(struct __pyx_ob
       *((unsigned int *) ( /* dim=1 */ (( /* dim=0 */ (__pyx_v_self-&gt;agent_positions.data + __pyx_t_5 * __pyx_v_self-&gt;agent_positions.strides[0]) ) + __pyx_t_6 * __pyx_v_self-&gt;agent_positions.strides[1]) )) = __pyx_v_dest_c;
 </pre><pre class="cython line score-0">&#xA0;<span class="">113</span>: </pre>
 <pre class="cython line score-0" onclick="(function(s){s.display=s.display==='block'?'none':'block'})(this.nextElementSibling.style)">+<span class="">114</span>:         <span class="bp">self</span><span class="o">.</span><span class="n">_compute_observations</span><span class="p">()</span></pre>
-<pre class='cython code score-0 '>  ((struct __pyx_vtabstruct_9mettagrid_6c_grid_Environment *)__pyx_v_self-&gt;__pyx_vtab)-&gt;_compute_observations(__pyx_v_self);<span class='error_goto'> if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 114, __pyx_L1_error)</span>
+<pre class='cython code score-0 '>  ((struct __pyx_vtabstruct_3env_9mettagrid_6c_grid_Environment *)__pyx_v_self-&gt;__pyx_vtab)-&gt;_compute_observations(__pyx_v_self);<span class='error_goto'> if (unlikely(PyErr_Occurred())) __PYX_ERR(0, 114, __pyx_L1_error)</span>
 </pre></div></body></html>
diff --git a/third_party/pufferlib b/third_party/pufferlib
--- a/third_party/pufferlib
+++ b/third_party/pufferlib
@@ -1 +1 @@
-Subproject commit 1460b4d5b58a17b6d494bf8cfae631690bf023a4
+Subproject commit 1460b4d5b58a17b6d494bf8cfae631690bf023a4-dirty
diff --git a/third_party/sample_factory b/third_party/sample_factory
index 5ffcbcc..9d990ea 160000
--- a/third_party/sample_factory
+++ b/third_party/sample_factory
@@ -1 +1 @@
-Subproject commit 5ffcbcc19482a8c5e63570591b45da62822ee87b
+Subproject commit 9d990eaf3fd40c635febe5b3e67d5c7d3bb7a9cb