diff --git a/devel/immer/Makefile b/devel/immer/Makefile
index 1ea1d45b4818..0ce19bf82890 100644
--- a/devel/immer/Makefile
+++ b/devel/immer/Makefile
@@ -1,36 +1,36 @@
 PORTNAME=	immer
 DISTVERSIONPREFIX=	v
-DISTVERSION=	0.8.1
+DISTVERSION=	0.9.0
 CATEGORIES=	devel
 
 MAINTAINER=	jhale@FreeBSD.org
 COMMENT=	Postmodern immutable and persistent data structures for C++
 WWW=		https://sinusoid.es/immer/
 
 LICENSE=	BSL
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
-USES=		cmake
+USES=		cmake pkgconfig
 USE_GITHUB=	yes
 GH_ACCOUNT=	arximboldi
 
 CMAKE_ON=	DISABLE_WERROR
 CMAKE_OFF=	immer_BUILD_DOCS \
 		immer_BUILD_EXTRAS
 
 NO_ARCH=	yes
 
 OPTIONS_DEFINE=	TEST
 
 TEST_BUILD_DEPENDS=	boehm-gc>=0:devel/boehm-gc \
 			boehm-gc-threaded>=0:devel/boehm-gc-threaded \
 			boost-libs>=0:devel/boost-libs \
 			catch>=0:devel/catch
 TEST_USES=		compiler:c++14-lang pkgconfig
 TEST_CMAKE_BOOL=	immer_BUILD_EXAMPLES \
 			immer_BUILD_TESTS
 TEST_ALL_TARGET=	install examples tests
 TEST_ALL_TARGET_OFF=	install
 TEST_TEST_TARGET=	test
 
 .include <bsd.port.mk>
diff --git a/devel/immer/distinfo b/devel/immer/distinfo
index ca28e20f5aed..65a65a74453a 100644
--- a/devel/immer/distinfo
+++ b/devel/immer/distinfo
@@ -1,3 +1,3 @@
-TIMESTAMP = 1696411685
-SHA256 (arximboldi-immer-v0.8.1_GH0.tar.gz) = de8411c84830864604bb685dc8f2e3c0dbdc40b95b2f6726092f7dcc85e75209
-SIZE (arximboldi-immer-v0.8.1_GH0.tar.gz) = 654638
+TIMESTAMP = 1766279467
+SHA256 (arximboldi-immer-v0.9.0_GH0.tar.gz) = 4e9f9a9018ac6c12f5fa92540feeedffb0a0a7db0de98c07ee62688cc329085a
+SIZE (arximboldi-immer-v0.9.0_GH0.tar.gz) = 745053
diff --git a/devel/immer/files/patch-cmake_FindBoehmGC.cmake b/devel/immer/files/patch-cmake_FindBoehmGC.cmake
index 8bc34f5c5e21..de43409ed283 100644
--- a/devel/immer/files/patch-cmake_FindBoehmGC.cmake
+++ b/devel/immer/files/patch-cmake_FindBoehmGC.cmake
@@ -1,11 +1,16 @@
---- cmake/FindBoehmGC.cmake.orig	2023-10-04 09:47:41 UTC
+CMake Error at cmake/FindBoehmGC.cmake:67 (check_c_source_runs):
+  Unknown CMake command "check_c_source_runs".
+
+https://github.com/arximboldi/immer/pull/315
+
+--- cmake/FindBoehmGC.cmake.orig	2025-12-02 21:25:10 UTC
 +++ cmake/FindBoehmGC.cmake
-@@ -57,7 +57,7 @@ IF (${CMAKE_SYSTEM_NAME} STREQUAL "FreeBSD")
- IF (${CMAKE_SYSTEM_NAME} STREQUAL "FreeBSD")
-   # checks if 'gc' supports 'GC_get_parallel' and if it does
-   # then use it
--  INCLUDE(${CMAKE_ROOT}/Modules/CheckCSourceCompiles.cmake)
-+  INCLUDE(${CMAKE_ROOT}/Modules/CheckCSourceRuns.cmake)
+@@ -52,7 +52,7 @@ if(${CMAKE_SYSTEM_NAME} STREQUAL "FreeBSD")
+ # For FreeBSD we need to use gc-threaded
+ if(${CMAKE_SYSTEM_NAME} STREQUAL "FreeBSD")
+   # checks if 'gc' supports 'GC_get_parallel' and if it does then use it
+-  include(${CMAKE_ROOT}/Modules/CheckCSourceCompiles.cmake)
++  include(${CMAKE_ROOT}/Modules/CheckCSourceRuns.cmake)
    # not sure if this links properly...
-   FIND_LIBRARY(BOEHM_GC_LIBRARIES NAMES gc
-     HINTS ${PC_BDW_GC_LIBDIR} ${PC_BDW_GC_LIBRARY_DIRS})
+   find_library(
+     BOEHM_GC_LIBRARIES
diff --git a/devel/immer/pkg-plist b/devel/immer/pkg-plist
index 9b67648df9bd..3a0256223e74 100644
--- a/devel/immer/pkg-plist
+++ b/devel/immer/pkg-plist
@@ -1,63 +1,102 @@
 include/immer/algorithm.hpp
 include/immer/array.hpp
 include/immer/array_transient.hpp
 include/immer/atom.hpp
 include/immer/box.hpp
 include/immer/config.hpp
 include/immer/detail/arrays/no_capacity.hpp
 include/immer/detail/arrays/node.hpp
 include/immer/detail/arrays/with_capacity.hpp
 include/immer/detail/combine_standard_layout.hpp
 include/immer/detail/hamts/bits.hpp
 include/immer/detail/hamts/champ.hpp
 include/immer/detail/hamts/champ_iterator.hpp
 include/immer/detail/hamts/node.hpp
 include/immer/detail/iterator_facade.hpp
 include/immer/detail/rbts/bits.hpp
 include/immer/detail/rbts/node.hpp
 include/immer/detail/rbts/operations.hpp
 include/immer/detail/rbts/position.hpp
 include/immer/detail/rbts/rbtree.hpp
 include/immer/detail/rbts/rbtree_iterator.hpp
 include/immer/detail/rbts/rrbtree.hpp
 include/immer/detail/rbts/rrbtree_iterator.hpp
 include/immer/detail/rbts/visitor.hpp
 include/immer/detail/ref_count_base.hpp
 include/immer/detail/type_traits.hpp
 include/immer/detail/util.hpp
 include/immer/experimental/detail/dvektor_impl.hpp
 include/immer/experimental/dvektor.hpp
+include/immer/extra/cereal/immer_array.hpp
+include/immer/extra/cereal/immer_box.hpp
+include/immer/extra/cereal/immer_map.hpp
+include/immer/extra/cereal/immer_set.hpp
+include/immer/extra/cereal/immer_table.hpp
+include/immer/extra/cereal/immer_vector.hpp
+include/immer/extra/io.hpp
+include/immer/extra/persist/cereal/archives.hpp
+include/immer/extra/persist/cereal/load.hpp
+include/immer/extra/persist/cereal/policy.hpp
+include/immer/extra/persist/cereal/save.hpp
+include/immer/extra/persist/detail/alias.hpp
+include/immer/extra/persist/detail/array/pool.hpp
+include/immer/extra/persist/detail/box/pool.hpp
+include/immer/extra/persist/detail/cereal/compact_map.hpp
+include/immer/extra/persist/detail/cereal/input_archive_util.hpp
+include/immer/extra/persist/detail/cereal/persistable.hpp
+include/immer/extra/persist/detail/cereal/pools.hpp
+include/immer/extra/persist/detail/cereal/wrap.hpp
+include/immer/extra/persist/detail/champ/champ.hpp
+include/immer/extra/persist/detail/champ/input.hpp
+include/immer/extra/persist/detail/champ/output.hpp
+include/immer/extra/persist/detail/champ/pool.hpp
+include/immer/extra/persist/detail/champ/traits.hpp
+include/immer/extra/persist/detail/common/pool.hpp
+include/immer/extra/persist/detail/names.hpp
+include/immer/extra/persist/detail/node_ptr.hpp
+include/immer/extra/persist/detail/rbts/input.hpp
+include/immer/extra/persist/detail/rbts/output.hpp
+include/immer/extra/persist/detail/rbts/pool.hpp
+include/immer/extra/persist/detail/rbts/traits.hpp
+include/immer/extra/persist/detail/rbts/traverse.hpp
+include/immer/extra/persist/detail/traits.hpp
+include/immer/extra/persist/detail/transform.hpp
+include/immer/extra/persist/detail/type_traverse.hpp
+include/immer/extra/persist/errors.hpp
+include/immer/extra/persist/hash_container_conversion.hpp
+include/immer/extra/persist/transform.hpp
+include/immer/extra/persist/types.hpp
+include/immer/extra/persist/xxhash/xxhash.hpp
+include/immer/extra/persist/xxhash/xxhash_64.cpp
 include/immer/flex_vector.hpp
 include/immer/flex_vector_transient.hpp
 include/immer/heap/cpp_heap.hpp
 include/immer/heap/debug_size_heap.hpp
 include/immer/heap/free_list_heap.hpp
-include/immer/heap/free_list_node.hpp
 include/immer/heap/gc_heap.hpp
 include/immer/heap/heap_policy.hpp
 include/immer/heap/identity_heap.hpp
 include/immer/heap/malloc_heap.hpp
 include/immer/heap/split_heap.hpp
 include/immer/heap/tags.hpp
 include/immer/heap/thread_local_free_list_heap.hpp
 include/immer/heap/unsafe_free_list_heap.hpp
-include/immer/heap/with_data.hpp
 include/immer/lock/no_lock_policy.hpp
 include/immer/lock/spinlock_policy.hpp
 include/immer/map.hpp
 include/immer/map_transient.hpp
 include/immer/memory_policy.hpp
 include/immer/refcount/enable_intrusive_ptr.hpp
 include/immer/refcount/no_refcount_policy.hpp
 include/immer/refcount/refcount_policy.hpp
 include/immer/refcount/unsafe_refcount_policy.hpp
 include/immer/set.hpp
 include/immer/set_transient.hpp
 include/immer/table.hpp
 include/immer/table_transient.hpp
 include/immer/transience/gc_transience_policy.hpp
 include/immer/transience/no_transience_policy.hpp
 include/immer/vector.hpp
 include/immer/vector_transient.hpp
 lib/cmake/Immer/ImmerConfig.cmake
 lib/cmake/Immer/ImmerConfigVersion.cmake