diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 9a8eaa78..3424d5b1 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -34,13 +34,13 @@ jobs:
       if: runner.os == 'Linux'
       run: |
         sudo apt install tinyproxy
-        LIBSSH2_VERSION=1.11.1 LIBGIT2_VERSION=1.8.4 /bin/sh build.sh test
+        LIBSSH2_VERSION=1.11.1 LIBGIT2_VERSION=1.9.0 /bin/sh build.sh test
 
     - name: macOS
       if: runner.os == 'macOS'
       run: |
         export OPENSSL_PREFIX=`brew --prefix openssl@1.1`
-        LIBSSH2_VERSION=1.11.1 LIBGIT2_VERSION=1.8.4 /bin/sh build.sh test
+        LIBSSH2_VERSION=1.11.1 LIBGIT2_VERSION=1.9.0 /bin/sh build.sh test
 
   aarch64:
     runs-on: ubuntu-24.04
@@ -57,7 +57,7 @@ jobs:
           apt-get update -q -y
           apt-get install -q -y cmake libssl-dev python3-dev python3-venv wget
         run: |
-          LIBSSH2_VERSION=1.11.1 LIBGIT2_VERSION=1.8.4 /bin/sh build.sh test
+          LIBSSH2_VERSION=1.11.1 LIBGIT2_VERSION=1.9.0 /bin/sh build.sh test
 
   s390x:
     runs-on: ubuntu-24.04
@@ -75,5 +75,5 @@ jobs:
           apt-get update -q -y
           apt-get install -q -y cmake libssl-dev python3-dev python3-venv wget
         run: |
-          LIBSSH2_VERSION=1.11.1 LIBGIT2_VERSION=1.8.4 /bin/sh build.sh test
+          LIBSSH2_VERSION=1.11.1 LIBGIT2_VERSION=1.9.0 /bin/sh build.sh test
       continue-on-error: true # Tests are expected to fail, see issue #812
diff --git a/Makefile b/Makefile
index b8a4cfc1..1cc945bb 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 .PHONY: build html
 
 build:
-	OPENSSL_VERSION=3.2.3 LIBSSH2_VERSION=1.11.1 LIBGIT2_VERSION=1.8.4 sh build.sh
+	OPENSSL_VERSION=3.2.3 LIBSSH2_VERSION=1.11.1 LIBGIT2_VERSION=1.9.0 sh build.sh
 
 html: build
 	make -C docs html
diff --git a/appveyor.yml b/appveyor.yml
index 76a1f4fa..1cc54798 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -35,7 +35,7 @@ build_script:
 # Clone, build and install libgit2
 - cmd: |
     set LIBGIT2=%APPVEYOR_BUILD_FOLDER%\venv
-    git clone --depth=1 -b v1.8.1 https://github.com/libgit2/libgit2.git libgit2
+    git clone --depth=1 -b v1.9.0 https://github.com/libgit2/libgit2.git libgit2
     cd libgit2
     cmake . -DBUILD_TESTS=OFF -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX="%LIBGIT2%" -G "%GENERATOR%"
     cmake --build . --target install
diff --git a/build.sh b/build.sh
index 944ed052..646e46a1 100644
--- a/build.sh
+++ b/build.sh
@@ -22,14 +22,14 @@
 #
 #   sh build.sh
 #
-# Build libgit2 1.8.4 (will use libssh2 if available), then build pygit2
+# Build libgit2 1.9.0 (will use libssh2 if available), then build pygit2
 # inplace:
 #
-#   LIBGIT2_VERSION=1.8.4 sh build.sh
+#   LIBGIT2_VERSION=1.9.0 sh build.sh
 #
-# Build libssh2 1.11.1 and libgit2 1.8.4, then build pygit2 inplace:
+# Build libssh2 1.11.1 and libgit2 1.9.0, then build pygit2 inplace:
 #
-#   LIBSSH2_VERSION=1.11.1 LIBGIT2_VERSION=1.8.4 sh build.sh
+#   LIBSSH2_VERSION=1.11.1 LIBGIT2_VERSION=1.9.0 sh build.sh
 #
 # Build inplace and run the tests:
 #
diff --git a/docs/install.rst b/docs/install.rst
index c0fe7087..bdfbbd86 100644
--- a/docs/install.rst
+++ b/docs/install.rst
@@ -57,7 +57,7 @@ Python requirements (these are specified in ``setup.py``):
 
 - cffi 1.17.0 or later
 
-Libgit2 **v1.8.x**; binary wheels already include libgit2, so you only need to
+Libgit2 **v1.9.x**; binary wheels already include libgit2, so you only need to
 worry about this if you install the source package.
 
 Optional libgit2 dependecies to support ssh and https:
@@ -86,6 +86,10 @@ of Python and the required libgit2 version.
 +-----------+----------------+------------+
 | pygit2    | Python         | libgit2    |
 +-----------+----------------+------------+
+| 1.17      | 3.10 - 3.13    | 1.9        |
++-----------+----------------+------------+
+| 1.16      | 3.10 - 3.13    | 1.8        |
++-----------+----------------+------------+
 | 1.15      | 3.9 - 3.12     | 1.8        |
 +-----------+----------------+------------+
 | 1.14      | 3.9 - 3.12     | 1.7        |
@@ -143,9 +147,9 @@ directory, do:
 
 .. code-block:: sh
 
-   $ wget https://github.com/libgit2/libgit2/archive/refs/tags/v1.8.1.tar.gz -O libgit2-1.8.1.tar.gz
-   $ tar xzf libgit2-1.8.1.tar.gz
-   $ cd libgit2-1.8.1/
+   $ wget https://github.com/libgit2/libgit2/archive/refs/tags/v1.9.0.tar.gz -O libgit2-1.9.0.tar.gz
+   $ tar xzf libgit2-1.9.0.tar.gz
+   $ cd libgit2-1.9.0/
    $ cmake .
    $ make
    $ sudo make install
@@ -227,9 +231,9 @@ Install libgit2 (see we define the installation prefix):
 
 .. code-block:: sh
 
-   $ wget https://github.com/libgit2/libgit2/archive/refs/tags/v1.8.1.tar.gz -O libgit2-1.8.1.tar.gz
-   $ tar xzf libgit2-1.8.1.tar.gz
-   $ cd libgit2-1.8.1/
+   $ wget https://github.com/libgit2/libgit2/archive/refs/tags/v1.9.0.tar.gz -O libgit2-1.9.0.tar.gz
+   $ tar xzf libgit2-1.9.0.tar.gz
+   $ cd libgit2-1.9.0/
    $ cmake . -DCMAKE_INSTALL_PREFIX=$LIBGIT2
    $ cmake --build . --target install
 
@@ -286,7 +290,7 @@ variable.  The following recipe shows you how to do it from a bash shell:
 .. code-block:: sh
 
    $ export LIBGIT2=C:/Dev/libgit2
-   $ git clone --depth=1 -b v1.8.1 https://github.com/libgit2/libgit2.git
+   $ git clone --depth=1 -b v1.9.0 https://github.com/libgit2/libgit2.git
    $ cd libgit2
    $ cmake . -DCMAKE_INSTALL_PREFIX=$LIBGIT2 -G "Visual Studio 14 Win64"
    $ cmake --build . --config release --target install
diff --git a/pygit2/decl/blame.h b/pygit2/decl/blame.h
index 5ccc8dd3..36205840 100644
--- a/pygit2/decl/blame.h
+++ b/pygit2/decl/blame.h
@@ -18,12 +18,15 @@ typedef struct git_blame_hunk {
 	git_oid final_commit_id;
 	size_t final_start_line_number;
 	git_signature *final_signature;
+	git_signature *final_committer;
 
 	git_oid orig_commit_id;
 	const char *orig_path;
 	size_t orig_start_line_number;
 	git_signature *orig_signature;
+	git_signature *orig_committer;
 
+	const char *summary;
 	char boundary;
 } git_blame_hunk;
 
diff --git a/pygit2/decl/config.h b/pygit2/decl/config.h
index 5cba6f7f..82003d73 100644
--- a/pygit2/decl/config.h
+++ b/pygit2/decl/config.h
@@ -18,7 +18,6 @@ typedef struct git_config_entry {
 	const char *origin_path;
 	unsigned int include_depth;
 	git_config_level_t level;
-	void (*free)(struct git_config_entry *entry);
 } git_config_entry;
 
 void git_config_entry_free(git_config_entry *);
diff --git a/pygit2/decl/remote.h b/pygit2/decl/remote.h
index 64b96442..d0e2c141 100644
--- a/pygit2/decl/remote.h
+++ b/pygit2/decl/remote.h
@@ -48,6 +48,7 @@ struct git_remote_callbacks {
 	git_remote_ready_cb remote_ready;
 	void *payload;
 	git_url_resolve_cb resolve_url;
+	int (*update_refs)(const char *refname, const git_oid *a, const git_oid *b, git_refspec *spec, void *data);
 };
 
 typedef struct {
diff --git a/pygit2/enums.py b/pygit2/enums.py
index e5bd54d9..b9c7b979 100644
--- a/pygit2/enums.py
+++ b/pygit2/enums.py
@@ -65,16 +65,16 @@ class BlameFlag(IntFlag):
     'Normal blame, the default'
 
     TRACK_COPIES_SAME_FILE = _pygit2.GIT_BLAME_TRACK_COPIES_SAME_FILE
-    'Not yet implemented and reserved for future use (as of libgit2 1.8.0).'
+    'Not yet implemented and reserved for future use (as of libgit2 1.9.0).'
 
     TRACK_COPIES_SAME_COMMIT_MOVES = _pygit2.GIT_BLAME_TRACK_COPIES_SAME_COMMIT_MOVES
-    'Not yet implemented and reserved for future use (as of libgit2 1.8.0).'
+    'Not yet implemented and reserved for future use (as of libgit2 1.9.0).'
 
     TRACK_COPIES_SAME_COMMIT_COPIES = _pygit2.GIT_BLAME_TRACK_COPIES_SAME_COMMIT_COPIES
-    'Not yet implemented and reserved for future use (as of libgit2 1.8.0).'
+    'Not yet implemented and reserved for future use (as of libgit2 1.9.0).'
 
     TRACK_COPIES_ANY_COMMIT_COPIES = _pygit2.GIT_BLAME_TRACK_COPIES_ANY_COMMIT_COPIES
-    'Not yet implemented and reserved for future use (as of libgit2 1.8.0).'
+    'Not yet implemented and reserved for future use (as of libgit2 1.9.0).'
 
     FIRST_PARENT = _pygit2.GIT_BLAME_FIRST_PARENT
     'Restrict the search of commits to those reachable following only the first parents.'
diff --git a/pyproject.toml b/pyproject.toml
index 20d4b61a..93feb5b7 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -7,7 +7,7 @@ skip = "pp3* *musllinux_aarch64 *musllinux_ppc64le"
 archs = ["auto"]
 build-frontend = "default"
 dependency-versions = "pinned"
-environment = {LIBGIT2_VERSION="1.8.4", LIBSSH2_VERSION="1.11.1", OPENSSL_VERSION="3.2.3", LIBGIT2="/project/ci"}
+environment = {LIBGIT2_VERSION="1.9.0", LIBSSH2_VERSION="1.11.1", OPENSSL_VERSION="3.2.3", LIBGIT2="/project/ci"}
 
 before-all = "sh build.sh"
 
@@ -21,7 +21,7 @@ repair-wheel-command = "LD_LIBRARY_PATH=/project/ci/lib auditwheel repair -w {de
 
 [tool.cibuildwheel.macos]
 archs = ["universal2"]
-environment = {LIBGIT2_VERSION="1.8.4", LIBSSH2_VERSION="1.11.1", OPENSSL_VERSION="3.2.3", LIBGIT2="/Users/runner/work/pygit2/pygit2/ci"}
+environment = {LIBGIT2_VERSION="1.9.0", LIBSSH2_VERSION="1.11.1", OPENSSL_VERSION="3.2.3", LIBGIT2="/Users/runner/work/pygit2/pygit2/ci"}
 repair-wheel-command = "DYLD_LIBRARY_PATH=/Users/runner/work/pygit2/pygit2/ci/lib delocate-wheel --require-archs {delocate_archs} -w {dest_dir} {wheel}"
 
 [tool.ruff]
diff --git a/src/types.h b/src/types.h
index c70c7eb7..ed070a01 100644
--- a/src/types.h
+++ b/src/types.h
@@ -33,8 +33,8 @@
 #include <git2.h>
 #include <git2/sys/filter.h>
 
-#if !(LIBGIT2_VER_MAJOR == 1 && LIBGIT2_VER_MINOR == 8)
-#error You need a compatible libgit2 version (1.8.x)
+#if !(LIBGIT2_VER_MAJOR == 1 && LIBGIT2_VER_MINOR == 9)
+#error You need a compatible libgit2 version (1.9.x)
 #endif
 
 /*