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diff --git a/include/git2/graph.h b/include/git2/graph.h
new file mode 100644
index 0000000..56edb2f
--- /dev/null
+++ b/include/git2/graph.h
@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+#ifndef INCLUDE_git_graph_h__
+#define INCLUDE_git_graph_h__
+
+#include "common.h"
+#include "types.h"
+#include "oid.h"
+
+/**
+ * @file git2/graph.h
+ * @brief Git graph traversal routines
+ * @defgroup git_revwalk Git graph traversal routines
+ * @ingroup Git
+ * @{
+ */
+GIT_BEGIN_DECL
+
+/**
+ * Count the number of unique commits between two commit objects
+ *
+ * There is no need for branches containing the commits to have any
+ * upstream relationship, but it helps to think of one as a branch and
+ * the other as its upstream, the `ahead` and `behind` values will be
+ * what git would report for the branches.
+ *
+ * @param ahead number of unique from commits in `upstream`
+ * @param behind number of unique from commits in `local`
+ * @param repo the repository where the commits exist
+ * @param local the commit for local
+ * @param upstream the commit for upstream
+ * @return 0 or an error code.
+ */
+GIT_EXTERN(int) git_graph_ahead_behind(size_t *ahead, size_t *behind, git_repository *repo, const git_oid *local, const git_oid *upstream);
+
+
+/**
+ * Determine if a commit is the descendant of another commit.
+ *
+ * Note that a commit is not considered a descendant of itself, in contrast
+ * to `git merge-base --is-ancestor`.
+ *
+ * @param repo the repository where the commits exist
+ * @param commit a previously loaded commit
+ * @param ancestor a potential ancestor commit
+ * @return 1 if the given commit is a descendant of the potential ancestor,
+ * 0 if not, error code otherwise.
+ */
+GIT_EXTERN(int) git_graph_descendant_of(
+	git_repository *repo,
+	const git_oid *commit,
+	const git_oid *ancestor);
+
+/**
+ * Determine if a commit is reachable from any of a list of commits by
+ * following parent edges.
+ *
+ * @param repo the repository where the commits exist
+ * @param commit a previously loaded commit
+ * @param length the number of commits in the provided `descendant_array`
+ * @param descendant_array oids of the commits
+ * @return 1 if the given commit is an ancestor of any of the given potential
+ * descendants, 0 if not, error code otherwise.
+ */
+GIT_EXTERN(int) git_graph_reachable_from_any(
+	git_repository *repo,
+	const git_oid *commit,
+	const git_oid descendant_array[],
+	size_t length);
+
+/** @} */
+GIT_END_DECL
+#endif