diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index f01338e..6a73789 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -5,9 +5,22 @@ find_package(Boost 1.62 REQUIRED COMPONENTS filesystem log)
 find_package(jsoncpp REQUIRED CONFIG) # 1.7.4 (Debian buster) has no version.
 find_package(CURL 7.52 REQUIRED)
 find_package(Threads REQUIRED)
-find_package(restclient-cpp 0.5 REQUIRED CONFIG)
+find_package(restclient-cpp 0.5 CONFIG)
 find_package(mastodon-cpp REQUIRED CONFIG)
 
+if(NOT ${restclient-cpp_FOUND})
+  find_file(restclient_h NAMES "restclient-cpp/restclient.h"
+    PATHS "${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_INCLUDEDIR}")
+  if("${restclient_h}" STREQUAL "restclient_h-NOTFOUND")
+    message(FATAL_ERROR "Could not find restclient-cpp.")
+  else()
+    message(WARNING
+      "Your distribution of restclient-cpp doesn't contain the *Config.cmake "
+      "recipes, but the files seem to be in the standard directories. "
+      "Let's hope this works.")
+  endif()
+endif()
+
 # Write version in header.
 configure_file (
   "${PROJECT_SOURCE_DIR}/src/version.hpp.in"