diff -Nru s2n-tls-1.1.1.orig/CMakeLists.txt s2n-tls-1.1.1/CMakeLists.txt
--- s2n-tls-1.1.1.orig/CMakeLists.txt	2021-10-05 00:47:12.000000000 +0000
+++ s2n-tls-1.1.1/CMakeLists.txt	2021-10-11 08:49:14.435094522 +0000
@@ -456,6 +456,10 @@
 
 target_link_libraries(${PROJECT_NAME} PUBLIC ${OS_LIBS} m)
 
+# Our ABI is not yet stable
+set_target_properties(${CMAKE_PROJECT_NAME} PROPERTIES VERSION 1.0.0)
+set_target_properties(${CMAKE_PROJECT_NAME} PROPERTIES SOVERSION 0unstable)
+
 target_include_directories(${PROJECT_NAME} PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>)
 target_include_directories(${PROJECT_NAME} PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/api> $<INSTALL_INTERFACE:include>)