diff --git a/build.zig b/build.zig
index cd7809d..75d2544 100644
--- a/build.zig
+++ b/build.zig
@@ -12,6 +12,8 @@ fn addEngineSources(c: *std.Build.Step.Compile) void {
             "src/component.c",
             "src/computer.c",
             "src/universe.c",
+            // components
+            "src/components/eeprom.c",
         },
     });
 }
diff --git a/src/components/eeprom.c b/src/components/eeprom.c
new file mode 100644
index 0000000..16d83f5
--- /dev/null
+++ b/src/components/eeprom.c
@@ -0,0 +1,135 @@
+#include "../neonucleus.h"
+
+void nn_eeprom_destroy(void *_, nn_component *component, nn_eeprom *eeprom) {
+    if(atomic_fetch_sub(&eeprom->refc, 1) > 1) return;
+
+    if(eeprom->deinit == NULL) {
+        eeprom->deinit(component, eeprom);
+    }
+}
+
+void nn_eeprom_getSize(nn_eeprom *eeprom, void *_, nn_component *component, nn_computer *computer) {
+    nn_return(computer, nn_values_integer(eeprom->getSize(component, eeprom->userdata)));
+}
+
+void nn_eeprom_getDataSize(nn_eeprom *eeprom, void *_, nn_component *component, nn_computer *computer) {
+    nn_return(computer, nn_values_integer(eeprom->getDataSize(component, eeprom->userdata)));
+}
+
+void nn_eeprom_getLabel(nn_eeprom *eeprom, void *_, nn_component *component, nn_computer *computer) {
+    char buf[NN_LABEL_SIZE];
+    size_t l = NN_LABEL_SIZE;
+    eeprom->getLabel(component, eeprom->userdata, buf, &l);
+    if(l == 0) {
+        nn_return(computer, nn_values_nil());
+    } else {
+        nn_return(computer, nn_values_string(buf, l));
+    }
+}
+
+void nn_eeprom_setLabel(nn_eeprom *eeprom, void *_, nn_component *component, nn_computer *computer) {
+    size_t l = 0;
+    nn_value label = nn_getArgument(computer, 0);
+    const char *buf = nn_toString(label, &l);
+    if(buf == NULL) {
+        nn_setCError(computer, "bad label (string expected)");
+        return;
+    }
+    l = eeprom->setLabel(component, eeprom->userdata, buf, l);
+    nn_return(computer, nn_values_string(buf, l));
+}
+
+void nn_eeprom_get(nn_eeprom *eeprom, void *_, nn_component *component, nn_computer *computer) {
+    size_t cap = eeprom->getSize(component, eeprom->userdata);
+    char *buf = nn_malloc(cap);
+    if(buf == NULL) {
+        nn_setCError(computer, "out of memory");
+        return;
+    }
+    size_t len = eeprom->get(component, eeprom->userdata, buf);
+    nn_return(computer, nn_values_string(buf, len));
+    nn_free(buf);
+}
+
+void nn_eeprom_set(nn_eeprom *eeprom, void *_, nn_component *component, nn_computer *computer) {
+    nn_value data = nn_getArgument(computer, 0);
+    size_t len;
+    const char *buf = nn_toString(data, &len);
+    if(len > eeprom->getSize(component, eeprom->userdata)) {
+
+    }
+    eeprom->set(component, eeprom->userdata, buf, len);
+}
+
+void nn_eeprom_getData(nn_eeprom *eeprom, void *_, nn_component *component, nn_computer *computer) {
+    size_t cap = eeprom->getDataSize(component, eeprom->userdata);
+    char *buf = nn_malloc(cap);
+    if(buf == NULL) {
+        nn_setCError(computer, "out of memory");
+        return;
+    }
+    int len = eeprom->getData(component, eeprom->userdata, buf);
+    if(len < 0) {
+        nn_return(computer, nn_values_nil());
+    } else {
+        nn_return(computer, nn_values_string(buf, len));
+    }
+    nn_free(buf);
+}
+
+void nn_eeprom_setData(nn_eeprom *eeprom, void *_, nn_component *component, nn_computer *computer) {
+    nn_value data = nn_getArgument(computer, 0);
+    size_t len;
+    const char *buf = nn_toString(data, &len);
+    eeprom->setData(component, eeprom->userdata, buf, len);
+}
+
+void nn_eeprom_isReadOnly(nn_eeprom *eeprom, void *_, nn_component *component, nn_computer *computer) {
+    nn_return(computer, nn_values_boolean(eeprom->isReadonly(component, eeprom->userdata)));
+}
+
+void nn_eeprom_makeReadonly(nn_eeprom *eeprom, void *_, nn_component *component, nn_computer *computer) {
+    eeprom->makeReadonly(component, eeprom->userdata);
+}
+
+// TODO: make good
+void nn_eeprom_getChecksum(nn_eeprom *eeprom, void *_, nn_component *component, nn_computer *computer) {
+    size_t cap = eeprom->getDataSize(component, eeprom->userdata);
+    char *buf = nn_malloc(cap);
+    if(buf == NULL) {
+        nn_setCError(computer, "out of memory");
+        return;
+    }
+    size_t len = eeprom->getData(component, eeprom->userdata, buf);
+    size_t sum = 0;
+    for(size_t i = 0; i < len; i++) {
+        sum += buf[i];
+    }
+    nn_free(buf);
+
+    nn_return(computer, nn_values_string((void *)&sum, sizeof(sum)));
+}
+
+void nn_loadEepromTable(nn_universe *universe) {
+    nn_componentTable *eepromTable = nn_newComponentTable("eeprom", NULL, NULL, (void *)nn_eeprom_destroy);
+    nn_storeUserdata(universe, "NN:EEPROM", eepromTable);
+
+    nn_defineMethod(eepromTable, "getSize", true, (void *)nn_eeprom_getSize, NULL, "getSize(): integer - Returns the maximum code capacity of the EEPROM.");
+    nn_defineMethod(eepromTable, "getDataSize", true, (void *)nn_eeprom_getDataSize, NULL, "getDataSize(): integer - Returns the maximum data capacity of the EEPROM.");
+    nn_defineMethod(eepromTable, "getLabel", false, (void *)nn_eeprom_getLabel, NULL, "getLabel(): string - Returns the current label.");
+    nn_defineMethod(eepromTable, "setLabel", false, (void *)nn_eeprom_setLabel, NULL, "setLabel(label: string): string - Sets the new label. Returns the actual label set to, which may be truncated.");
+    nn_defineMethod(eepromTable, "get", false, (void *)nn_eeprom_get, NULL, "get(): string - Reads the current code contents.");
+    nn_defineMethod(eepromTable, "set", false, (void *)nn_eeprom_set, NULL, "set(data: string) - Sets the current code contents.");
+    nn_defineMethod(eepromTable, "getData", false, (void *)nn_eeprom_getData, NULL, "getData(): string - Reads the current data contents.");
+    nn_defineMethod(eepromTable, "setData", false, (void *)nn_eeprom_setData, NULL, "setData(data: string) - Sets the current data contents.");
+    nn_defineMethod(eepromTable, "isReadOnly", false, (void *)nn_eeprom_isReadOnly, NULL, "isReadOnly(): boolean - Returns whether this EEPROM is read-only.");
+    nn_defineMethod(eepromTable, "makeReadOnly", false, (void *)nn_eeprom_makeReadonly, NULL, "makeReadOnly() - Makes the current EEPROM read-only. Normally, this cannot be undone.");
+    nn_defineMethod(eepromTable, "makeReadonly", false, (void *)nn_eeprom_makeReadonly, NULL, "makeReadonly() - Legacy alias to makeReadOnly()");
+    nn_defineMethod(eepromTable, "getChecksum", false, (void *)nn_eeprom_getChecksum, NULL, "getChecksum(): string - Returns a checksum of the data on the EEPROM.");
+}
+
+nn_component *nn_addEeprom(nn_computer *computer, nn_address address, int slot, nn_eeprom *eeprom) {
+    nn_componentTable *eepromTable = nn_queryUserdata(nn_getUniverse(computer), "NN:EEPROM");
+
+    return nn_newComponent(computer, address, slot, eepromTable, eeprom);
+}
diff --git a/src/computer.c b/src/computer.c
index 06e48dd..7313faf 100644
--- a/src/computer.c
+++ b/src/computer.c
@@ -44,6 +44,8 @@ nn_computer *nn_newComputer(nn_universe *universe, nn_address address, nn_archit
     c->temperature = 30;
     c->roomTemperature = 30;
     c->temperatureCoefficient = 1;
+    c->callCost = 0;
+    c->callBudget = 256;
 
     // Setup Architecture
     c->archState = c->arch->setup(c, c->arch->userdata);
@@ -58,6 +60,10 @@ nn_computer *nn_newComputer(nn_universe *universe, nn_address address, nn_archit
     return c;
 }
 
+nn_universe *nn_getUniverse(nn_computer *computer) {
+    return computer->universe;
+}
+
 void nn_setTmpAddress(nn_computer *computer, nn_address tmp) {
     nn_free(computer->tmpAddress);
     computer->tmpAddress = nn_strdup(tmp);
@@ -72,6 +78,7 @@ nn_address nn_getTmpAddress(nn_computer *computer) {
 }
 
 int nn_tickComputer(nn_computer *computer) {
+    computer->callCost = 0;
     computer->state = NN_STATE_RUNNING;
     nn_clearError(computer);
     computer->arch->tick(computer, computer->archState, computer->arch->userdata);
@@ -206,6 +213,26 @@ bool nn_isUser(nn_computer *computer, const char *name) {
     return false;
 }
 
+void nn_setCallBudget(nn_computer *computer, size_t callBudget) {
+    computer->callBudget = callBudget;
+}
+
+size_t nn_getCallBudget(nn_computer *computer) {
+    return computer->callBudget;
+}
+
+void nn_callCost(nn_computer *computer, size_t cost) {
+    computer->callCost += cost;
+}
+
+size_t nn_getCallCost(nn_computer *computer) {
+    return computer->callCost;
+}
+
+bool nn_isOverworked(nn_computer *computer) {
+    return computer->callCost >= computer->callBudget;
+}
+
 int nn_getState(nn_computer *computer) {
     return computer->state;
 }
@@ -335,9 +362,9 @@ nn_component *nn_newComponent(nn_computer *computer, nn_address address, int slo
     c->slot = slot;
     c->computer = computer;
     if(table->constructor == NULL) {
-        c->statePtr = NULL;
+        c->statePtr = userdata;
     } else {
-        c->statePtr = table->constructor(table->userdata);
+        c->statePtr = table->constructor(table->userdata, userdata);
     }
     return c;
 }
@@ -353,7 +380,7 @@ void nn_removeComponent(nn_computer *computer, nn_address address) {
 void nn_destroyComponent(nn_component *component) {
     nn_free(component->address);
     if(component->table->destructor != NULL) {
-        component->table->destructor(component->table->userdata, component->statePtr);
+        component->table->destructor(component->table->userdata, component, component->statePtr);
     }
     component->address = NULL; // marks component as freed
 }
diff --git a/src/computer.h b/src/computer.h
index 1e4ed8b..60fa5ba 100644
--- a/src/computer.h
+++ b/src/computer.h
@@ -40,6 +40,8 @@ typedef struct nn_computer {
     double temperature;
     double temperatureCoefficient;
     double roomTemperature;
+    size_t callCost;
+    size_t callBudget;
 } nn_computer;
 
 #endif
diff --git a/src/emulator.c b/src/emulator.c
index ee06bee..1ed238f 100644
--- a/src/emulator.c
+++ b/src/emulator.c
@@ -4,17 +4,61 @@
 #include <string.h>
 #include "neonucleus.h"
 #include "testLuaArch.h"
-
-void emulator_debugPrint(void *componentUserdata, void *methodUserdata, nn_component *component, nn_computer *computer) {
-    nn_value msg = nn_getArgument(computer, 0);
-    const char *m = nn_toCString(msg);
-    printf("[DEBUG] %s\n", m);
-    nn_return(computer, nn_values_integer(strlen(m)));
+    
+size_t ne_eeprom_getSize(nn_component *component, void *_) {
+    return 4096;
 }
 
+size_t ne_eeprom_getDataSize(nn_component *component, void *_) {
+    return 1024;
+}
+
+void ne_eeprom_getLabel(nn_component *component, void *_, char *buf, size_t *buflen) {
+    *buflen = 0;
+}
+
+size_t ne_eeprom_setLabel(nn_component *component, void *_, const char *buf, size_t buflen) {
+    return 0;
+}
+
+const char *ne_eeprom_location(nn_address address) {
+    static char buffer[256];
+    snprintf(buffer, 256, "data/%s", address);
+    return buffer;
+}
+
+size_t ne_eeprom_get(nn_component *component, void *_, char *buf) {
+    FILE *f = fopen(ne_eeprom_location(nn_getComponentAddress(component)), "rb");
+    fseek(f, 0, SEEK_END);
+    size_t len = ftell(f);
+    fseek(f, 0, SEEK_SET);
+    fread(buf, sizeof(char), len, f);
+    fclose(f);
+    return len;
+}
+
+void ne_eeprom_set(nn_component *component, void *_, const char *buf, size_t len) {
+    FILE *f = fopen(ne_eeprom_location(nn_getComponentAddress(component)), "wb");
+    fwrite(buf, sizeof(char), len, f);
+    fclose(f);
+}
+
+int ne_eeprom_getData(nn_component *component, void *_, char *buf) {
+    return -1;
+}
+
+void ne_eeprom_setData(nn_component *component, void *_, const char *buf, size_t len) {}
+    
+bool ne_eeprom_isReadonly(nn_component *component, void *userdata) {
+    return false;
+}
+
+void ne_eeprom_makeReadonly(nn_component *component, void *userdata) {}
+
 int main() {
     printf("Setting up universe\n");
     nn_universe *universe = nn_newUniverse();
+    nn_loadCoreComponentTables(universe);
 
     nn_architecture *arch = testLuaArch_getArchitecture("src/sandbox.lua");
     assert(arch != NULL && "Loading architecture failed");
@@ -24,10 +68,23 @@ int main() {
     nn_setEnergyInfo(computer, 5000, 5000);
     nn_addSupportedArchitecture(computer, arch);
 
-    nn_componentTable *t = nn_newComponentTable("debugPrint", NULL, NULL, NULL);
-    nn_defineMethod(t, "log", false, emulator_debugPrint, NULL, "logs stuff");
+    nn_eeprom genericEEPROM = {
+        .userdata = NULL,
+        .refc = 1,
+        .deinit = NULL,
+        .getSize = ne_eeprom_getSize,
+        .getDataSize = ne_eeprom_getDataSize,
+        .getLabel = ne_eeprom_getLabel,
+        .setLabel = ne_eeprom_setLabel,
+        .get = ne_eeprom_get,
+        .set = ne_eeprom_set,
+        .getData = ne_eeprom_getData,
+        .setData = ne_eeprom_setData,
+        .isReadonly = ne_eeprom_isReadonly,
+        .makeReadonly = ne_eeprom_makeReadonly,
+    };
 
-    nn_newComponent(computer, "debugPrint", -1, t, NULL);
+    nn_addEeprom(computer, "luaBios.lua", 0, &genericEEPROM);
 
     double lastTime = nn_realTime();
     while(true) {
diff --git a/src/lock.c b/src/lock.c
index 6fc672d..c0985e1 100644
--- a/src/lock.c
+++ b/src/lock.c
@@ -13,13 +13,16 @@ nn_guard *nn_newGuard() {
 }
 
 void nn_lock(nn_guard *guard) {
+    if(guard == NULL) return;
     mtx_lock(&guard->m);
 }
 
 void nn_unlock(nn_guard *guard) {
+    if(guard == NULL) return;
     mtx_unlock(&guard->m);
 }
 
 void nn_deleteGuard(nn_guard *guard) {
+    if(guard == NULL) return;
     mtx_destroy(&guard->m);
 }
diff --git a/src/neonucleus.h b/src/neonucleus.h
index bb1a195..39b8718 100644
--- a/src/neonucleus.h
+++ b/src/neonucleus.h
@@ -4,6 +4,7 @@
 #include <stddef.h>
 #include <stdint.h>
 #include <stdbool.h>
+#include <stdatomic.h>
 
 // Based off https://stackoverflow.com/questions/5919996/how-to-detect-reliably-mac-os-x-ios-linux-windows-in-c-preprocessor
 #if defined(WIN32) || defined(_WIN32) || defined(__WIN32__) || defined(__NT__)
@@ -58,6 +59,9 @@
 #define NN_MAX_USER_SIZE 128
 #define NN_MAX_SIGNAL_SIZE 8192
 #define NN_OVERHEAT_MIN 100
+#define NN_CALL_HEAT 0.05
+#define NN_CALL_COST 1
+#define NN_LABEL_SIZE 128
 
 typedef struct nn_guard nn_guard;
 typedef struct nn_universe nn_universe;
@@ -151,6 +155,7 @@ void nn_setClock(nn_universe *universe, nn_clock_t *clock, void *userdata);
 double nn_getTime(nn_universe *universe);
 
 nn_computer *nn_newComputer(nn_universe *universe, nn_address address, nn_architecture *arch, void *userdata, size_t memoryLimit, size_t componentLimit);
+nn_universe *nn_getUniverse(nn_computer *computer);
 int nn_tickComputer(nn_computer *computer);
 double nn_getUptime(nn_computer *computer);
 size_t nn_getComputerMemoryUsed(nn_computer *computer);
@@ -170,6 +175,11 @@ const char *nn_addUser(nn_computer *computer, const char *name);
 void nn_deleteUser(nn_computer *computer, const char *name);
 const char *nn_indexUser(nn_computer *computer, size_t idx);
 bool nn_isUser(nn_computer *computer, const char *name);
+void nn_setCallBudget(nn_computer *computer, size_t callBudget);
+size_t nn_getCallBudget(nn_computer *computer);
+void nn_callCost(nn_computer *computer, size_t cost);
+size_t nn_getCallCost(nn_computer *computer);
+bool nn_isOverworked(nn_computer *computer);
 
 /* The memory returned can be freed with nn_free() */
 char *nn_serializeProgram(nn_computer *computer, size_t *len);
@@ -259,8 +269,8 @@ nn_component **nn_listComponent(nn_computer *computer, size_t *len);
 
 // Component VTable stuff
 
-typedef void *nn_componentConstructor(void *userdata);
-typedef void *nn_componentDestructor(void *tableUserdata, void *componentUserdata);
+typedef void *nn_componentConstructor(void *tableUserdata, void *componentUserdata);
+typedef void *nn_componentDestructor(void *tableUserdata, nn_component *component, void *componentUserdata);
 typedef void nn_componentMethod(void *componentUserdata, void *methodUserdata, nn_component *component, nn_computer *computer);
 
 nn_componentTable *nn_newComponentTable(const char *typeName, void *userdata, nn_componentConstructor *constructor, nn_componentDestructor *destructor);
@@ -314,4 +324,34 @@ const char *nn_toString(nn_value val, size_t *len);
  */
 size_t nn_measurePacketSize(nn_value *vals, size_t len);
 
+// COMPONENTS
+
+/* Loads the vtables for the default implementations of those components */
+void nn_loadCoreComponentTables(nn_universe *universe);
+
+// loading each component
+void nn_loadEepromTable(nn_universe *universe);
+
+// the helpers
+
+// EEPROM
+typedef struct nn_eeprom {
+    void *userdata;
+    atomic_size_t refc;
+    void (*deinit)(nn_component *component, void *userdata);
+
+    // methods
+    size_t (*getSize)(nn_component *component, void *userdata);
+    size_t (*getDataSize)(nn_component *component, void *userdata);
+    void (*getLabel)(nn_component *component, void *userdata, char *buf, size_t *buflen);
+    size_t (*setLabel)(nn_component *component, void *userdata, const char *buf, size_t buflen);
+    size_t (*get)(nn_component *component, void *userdata, char *buf);
+    void (*set)(nn_component *component, void *userdata, const char *buf, size_t len);
+    int (*getData)(nn_component *component, void *userdata, char *buf);
+    void (*setData)(nn_component *component, void *userdata, const char *buf, size_t len);
+    bool (*isReadonly)(nn_component *component, void *userdata);
+    void (*makeReadonly)(nn_component *component, void *userdata);
+} nn_eeprom;
+nn_component *nn_addEeprom(nn_computer *computer, nn_address address, int slot, nn_eeprom *eeprom);
+
 #endif
diff --git a/src/sandbox.lua b/src/sandbox.lua
index 3eb1946..5dc6f79 100644
--- a/src/sandbox.lua
+++ b/src/sandbox.lua
@@ -1,11 +1,35 @@
-print(component.doc("debugPrint", "log"))
-print(component.invoke("debugPrint", "log", "Absolute cinema"))
+-- sandbox stuff
 
-computer.pushSignal("stuff", 123, "a", false, nil)
-computer.pushSignal("stuf2", 456, "b", true, "shit")
-computer.pushSignal("stuf3", 789, "c", false, -13)
+local clist = component.list
+function component.list(type, exact)
+    local m = clist()
+    if not type then return m end
+    local t = {}
+    for addr, kind in pairs(m) do
+        if exact then
+            if type == kind then
+                t[addr] = kind
+            end
+        else
+            if string.match(kind, type) then
+                t[addr] = kind
+            end
+        end
+    end
+    setmetatable(t, {
+        __call = function()
+            return next(t)
+        end,
+    })
+    return t
+end
 
-print(computer.popSignal())
-print(computer.popSignal())
-print(computer.popSignal())
-print(computer.popSignal())
+for addr, kind in pairs(component.list()) do
+    if kind == "eeprom" then
+        local data = component.invoke(addr, "get")
+        assert(load(data, "=eeprom"))()
+        return
+    end
+end
+
+error("no bios")
diff --git a/src/testLuaArch.c b/src/testLuaArch.c
index 914bef1..9a83239 100644
--- a/src/testLuaArch.c
+++ b/src/testLuaArch.c
@@ -254,10 +254,27 @@ static int testLuaArch_computer_popSignal(lua_State *L) {
     return retc;
 }
 
+static int testLuaArch_computer_users(lua_State *L) {
+    nn_computer *c = testLuaArch_getComputer(L);
+    size_t i = 0;
+    while(true) {
+        const char *name = nn_indexUser(c, i);
+        if(name == NULL) break;
+        lua_pushstring(L, name);
+        i++;
+    }
+    return i;
+}
+
 static int testLuaArch_component_list(lua_State *L) {
     nn_computer *c = testLuaArch_getComputer(L);
     size_t len = 0;
     nn_component **components = nn_listComponent(c, &len);
+    if(components == NULL) {
+        lua_pushnil(L);
+        lua_pushstring(L, "out of memory");
+        return 2;
+    }
     lua_createtable(L, 0, len);
     int list = lua_gettop(L);
     for(size_t i = 0; i < len; i++) {
@@ -292,6 +309,62 @@ static int testLuaArch_component_doc(lua_State *L) {
     return 1;
 }
 
+static int testLuaArch_component_fields(lua_State *L) {
+    lua_createtable(L, 0, 0);
+    return 1;
+}
+
+static int testLuaArch_component_methods(lua_State *L) {
+    nn_computer *c = testLuaArch_getComputer(L);
+    const char *addr = luaL_checkstring(L, 1);
+    nn_component *component = nn_findComponent(c, (char *)addr);
+    if(component == NULL) {
+        lua_pushnil(L);
+        lua_pushstring(L, "no such component");
+        return 2;
+    }
+    nn_componentTable *table = nn_getComponentTable(component);
+    lua_createtable(L, 0, 0);
+    int methods = lua_gettop(L);
+
+    size_t i = 0;
+    while(true) {
+        bool direct = false;
+        const char *name = nn_getTableMethod(table, i, &direct);
+        if(name == NULL) break;
+        i++;
+        lua_pushboolean(L, direct);
+        lua_setfield(L, methods, name);
+    }
+
+    return 1;
+}
+
+static int testLuaArch_component_slot(lua_State *L) {
+    nn_computer *c = testLuaArch_getComputer(L);
+    const char *addr = luaL_checkstring(L, 1);
+    nn_component *component = nn_findComponent(c, (char *)addr);
+    if(component == NULL) {
+        lua_pushnil(L);
+        lua_pushstring(L, "no such component");
+        return 2;
+    }
+    lua_pushinteger(L, nn_getComponentSlot(component));
+    return 1;
+}
+
+static int testLuaArch_component_type(lua_State *L) {
+    nn_computer *c = testLuaArch_getComputer(L);
+    const char *addr = luaL_checkstring(L, 1);
+    nn_component *component = nn_findComponent(c, (char *)addr);
+    if(component == NULL) {
+        lua_pushnil(L);
+        lua_pushstring(L, "no such component");
+        return 2;
+    }
+    lua_pushstring(L, nn_getComponentType(nn_getComponentTable(component)));
+    return 1;
+}
 
 static int testLuaArch_component_invoke(lua_State *L) {
     nn_computer *c = testLuaArch_getComputer(L);
@@ -314,6 +387,10 @@ static int testLuaArch_component_invoke(lua_State *L) {
         lua_pushstring(L, "no such method");
         return 2;
     }
+    if(nn_getError(c) != NULL) {
+        nn_resetCall(c);
+        luaL_error(L, "%s", nn_getError(c));
+    }
     size_t retc = nn_getReturnCount(c);
     for(size_t i = 0; i < retc; i++) {
         testLuaArch_pushValue(L, nn_getReturn(c, i));
@@ -359,6 +436,8 @@ void testLuaArch_loadEnv(lua_State *L) {
     lua_setfield(L, computer, "pushSignal");
     lua_pushcfunction(L, testLuaArch_computer_popSignal);
     lua_setfield(L, computer, "popSignal");
+    lua_pushcfunction(L, testLuaArch_computer_users);
+    lua_setfield(L, computer, "users");
     lua_setglobal(L, "computer");
 
     lua_createtable(L, 0, 10);
@@ -367,8 +446,16 @@ void testLuaArch_loadEnv(lua_State *L) {
     lua_setfield(L, component, "list");
     lua_pushcfunction(L, testLuaArch_component_doc);
     lua_setfield(L, component, "doc");
+    lua_pushcfunction(L, testLuaArch_component_fields);
+    lua_setfield(L, component, "fields");
+    lua_pushcfunction(L, testLuaArch_component_methods);
+    lua_setfield(L, component, "methods");
     lua_pushcfunction(L, testLuaArch_component_invoke);
     lua_setfield(L, component, "invoke");
+    lua_pushcfunction(L, testLuaArch_component_slot);
+    lua_setfield(L, component, "slot");
+    lua_pushcfunction(L, testLuaArch_component_type);
+    lua_setfield(L, component, "type");
     lua_setglobal(L, "component");
 }
 
diff --git a/src/universe.c b/src/universe.c
index 12384de..d8cfb4b 100644
--- a/src/universe.c
+++ b/src/universe.c
@@ -43,3 +43,7 @@ void nn_storeUserdata(nn_universe *universe, const char *name, void *data) {
 double nn_getTime(nn_universe *universe) {
     return universe->currentClock(universe->clockUserdata);
 }
+
+void nn_loadCoreComponentTables(nn_universe *universe) {
+    nn_loadEepromTable(universe);
+}