diff --git a/api/src/main/java/dev/xhyrom/lighteco/api/event/EventBus.java b/api/src/main/java/dev/xhyrom/lighteco/api/event/EventBus.java
new file mode 100644
index 0000000..401c9a3
--- /dev/null
+++ b/api/src/main/java/dev/xhyrom/lighteco/api/event/EventBus.java
@@ -0,0 +1,11 @@
+package dev.xhyrom.lighteco.api.event;
+
+import org.checkerframework.checker.nullness.qual.NonNull;
+
+import java.util.function.Consumer;
+
+public interface EventBus {
+    <T extends LightEcoEvent> @NonNull EventSubscription<T> subscribe(@NonNull Class<T> eventClass, @NonNull Consumer<? super T> subscriber);
+
+    <T extends LightEcoEvent> @NonNull EventSubscription<T> subscribe(Object plugin, @NonNull Class<T> eventClass, @NonNull Consumer<? super T> subscriber);
+}
diff --git a/api/src/main/java/dev/xhyrom/lighteco/api/event/EventSubscription.java b/api/src/main/java/dev/xhyrom/lighteco/api/event/EventSubscription.java
new file mode 100644
index 0000000..b530040
--- /dev/null
+++ b/api/src/main/java/dev/xhyrom/lighteco/api/event/EventSubscription.java
@@ -0,0 +1,13 @@
+package dev.xhyrom.lighteco.api.event;
+
+import org.checkerframework.checker.nullness.qual.NonNull;
+
+import java.util.function.Consumer;
+
+public interface EventSubscription<T extends LightEcoEvent> extends AutoCloseable {
+    @NonNull Class<T> getEventClass();
+
+    boolean isActive();
+
+    @NonNull Consumer<? super T> getHandler();
+}
diff --git a/api/src/main/java/dev/xhyrom/lighteco/api/event/LightEcoEvent.java b/api/src/main/java/dev/xhyrom/lighteco/api/event/LightEcoEvent.java
new file mode 100644
index 0000000..e3ab9c3
--- /dev/null
+++ b/api/src/main/java/dev/xhyrom/lighteco/api/event/LightEcoEvent.java
@@ -0,0 +1,10 @@
+package dev.xhyrom.lighteco.api.event;
+
+import dev.xhyrom.lighteco.api.LightEco;
+import org.checkerframework.checker.nullness.qual.NonNull;
+
+public interface LightEcoEvent {
+    @NonNull LightEco getLightEco();
+
+    @NonNull Class<? extends LightEcoEvent> getEventClass();
+}
diff --git a/api/src/main/java/dev/xhyrom/lighteco/api/event/currency/CurrencyRegisterEvent.java b/api/src/main/java/dev/xhyrom/lighteco/api/event/currency/CurrencyRegisterEvent.java
new file mode 100644
index 0000000..fcdf5fd
--- /dev/null
+++ b/api/src/main/java/dev/xhyrom/lighteco/api/event/currency/CurrencyRegisterEvent.java
@@ -0,0 +1,11 @@
+package dev.xhyrom.lighteco.api.event.currency;
+
+import dev.xhyrom.lighteco.api.event.LightEcoEvent;
+import dev.xhyrom.lighteco.api.event.util.Position;
+import dev.xhyrom.lighteco.api.model.currency.Currency;
+import org.checkerframework.checker.nullness.qual.NonNull;
+
+public interface CurrencyRegisterEvent extends LightEcoEvent {
+    @Position(0)
+    @NonNull Currency<?> getCurrency();
+}
diff --git a/api/src/main/java/dev/xhyrom/lighteco/api/event/util/Position.java b/api/src/main/java/dev/xhyrom/lighteco/api/event/util/Position.java
new file mode 100644
index 0000000..2f43124
--- /dev/null
+++ b/api/src/main/java/dev/xhyrom/lighteco/api/event/util/Position.java
@@ -0,0 +1,21 @@
+package dev.xhyrom.lighteco.api.event.util;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Represents the position (index) of a parameter within an event.
+ * Used for information purposes only.
+ */
+@Target(ElementType.METHOD)
+@Retention(RetentionPolicy.SOURCE)
+public @interface Position {
+    /**
+     * Represents the position (index) of a parameter.
+     *
+     * @return the position (index)
+     */
+    int value();
+}