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diff --git a/include/serd/event.h b/include/serd/event.h
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+++ b/include/serd/event.h
@@ -0,0 +1,99 @@
+// Copyright 2011-2022 David Robillard <d@drobilla.net>
+// SPDX-License-Identifier: ISC
+
+#ifndef SERD_EVENT_H
+#define SERD_EVENT_H
+
+#include "serd/attributes.h"
+#include "serd/node.h"
+#include "serd/statement.h"
+#include "serd/status.h"
+
+SERD_BEGIN_DECLS
+
+/**
+   @defgroup serd_event Events
+   @ingroup serd_streaming
+   @{
+*/
+
+/// Type of a SerdEvent
+typedef enum {
+  SERD_BASE      = 1, ///< Base URI changed
+  SERD_PREFIX    = 2, ///< New URI prefix
+  SERD_STATEMENT = 3, ///< Statement
+  SERD_END       = 4, ///< End of anonymous node
+} SerdEventType;
+
+/**
+   Event for base URI changes.
+
+   Emitted whenever the base URI changes.
+*/
+typedef struct {
+  SerdEventType                type; ///< #SERD_BASE
+  const SerdNode* SERD_NONNULL uri;  ///< Base URI
+} SerdBaseEvent;
+
+/**
+   Event for namespace definitions.
+
+   Emitted whenever a prefix is defined.
+*/
+typedef struct {
+  SerdEventType                type; ///< #SERD_PREFIX
+  const SerdNode* SERD_NONNULL name; ///< Prefix name
+  const SerdNode* SERD_NONNULL uri;  ///< Namespace URI
+} SerdPrefixEvent;
+
+/**
+   Event for statements.
+
+   Emitted for every statement.
+*/
+typedef struct {
+  SerdEventType                     type;      ///< #SERD_STATEMENT
+  SerdStatementFlags                flags;     ///< Flags for pretty-printing
+  const SerdStatement* SERD_NONNULL statement; ///< Statement
+} SerdStatementEvent;
+
+/**
+   Event for the end of anonymous node descriptions.
+
+   This is emitted to indicate that the given anonymous node will no longer be
+   described.  This is used by the writer which may, for example, need to
+   write a delimiter.
+*/
+typedef struct {
+  SerdEventType                type; ///< #SERD_END
+  const SerdNode* SERD_NONNULL node; ///< Anonymous node that is finished
+} SerdEndEvent;
+
+/**
+   An event in a data stream.
+
+   Streams of data are represented as a series of events.  Events represent
+   everything that can occur in an RDF document, and are used to plumb together
+   different components.  For example, when parsing a document, a reader emits
+   a stream of events which can be sent to a writer to rewrite a document, or
+   to an inserter to build a model in memory.
+*/
+typedef union {
+  SerdEventType      type;      ///< Event type (always set)
+  SerdBaseEvent      base;      ///< Base URI changed
+  SerdPrefixEvent    prefix;    ///< New namespace prefix
+  SerdStatementEvent statement; ///< Statement
+  SerdEndEvent       end;       ///< End of anonymous node
+} SerdEvent;
+
+/// Function for handling events
+typedef SerdStatus (*SerdEventFunc)(void* SERD_NULLABLE           handle,
+                                    const SerdEvent* SERD_NONNULL event);
+
+/**
+   @}
+*/
+
+SERD_END_DECLS
+
+#endif // SERD_EVENT_H