diff --git a/Makefile b/Makefile
index fe714d2ba393..c15648d7fc37 100644
--- a/Makefile
+++ b/Makefile
@@ -39,9 +39,9 @@ override FLAGS += -D strict_multi_assign -D preview_overload_order $(if $(releas
 SPEC_WARNINGS_OFF := --exclude-warnings spec/std --exclude-warnings spec/compiler --exclude-warnings spec/primitives
 SPEC_FLAGS := $(if $(verbose),-v )$(if $(junit_output),--junit_output $(junit_output) )$(if $(order),--order=$(order) )
 CRYSTAL_CONFIG_LIBRARY_PATH := '$$ORIGIN/../lib/crystal'
-CRYSTAL_CONFIG_BUILD_COMMIT := $(shell git rev-parse --short HEAD 2> /dev/null)
+CRYSTAL_CONFIG_BUILD_COMMIT ?= $(shell git rev-parse --short HEAD 2> /dev/null)
 CRYSTAL_CONFIG_PATH := '$$ORIGIN/../share/crystal/src'
-SOURCE_DATE_EPOCH := $(shell (git show -s --format=%ct HEAD || stat -c "%Y" Makefile || stat -f "%m" Makefile) 2> /dev/null)
+SOURCE_DATE_EPOCH ?= $(shell (git show -s --format=%ct HEAD || stat -c "%Y" Makefile || stat -f "%m" Makefile) 2> /dev/null)
 ifeq ($(shell command -v ld.lld >/dev/null && uname -s),Linux)
   EXPORT_CC ?= CC="$(CC) -fuse-ld=lld"
 endif
diff --git a/src/compiler/crystal/config.cr b/src/compiler/crystal/config.cr
index eb77b9e8886f..2f71aa49815c 100644
--- a/src/compiler/crystal/config.cr
+++ b/src/compiler/crystal/config.cr
@@ -15,13 +15,17 @@ module Crystal
     end
 
     def self.description
-      formatted_sha = "[#{build_commit}] " if build_commit
-      <<-DOC
-        Crystal #{version} #{formatted_sha}(#{date})
+      String.build do |io|
+        io << "Crystal " << version
+        io << " [" << build_commit << "]" if build_commit
+        io << " (" << date << ")" unless date.empty?
 
-        LLVM: #{llvm_version}
-        Default target: #{self.host_target}
-        DOC
+        io << "\n\nThe compiler was not built in release mode." unless release_mode?
+
+        io << "\n\nLLVM: " << llvm_version
+        io << "\nDefault target: " << host_target
+        io << "\n"
+      end
     end
 
     def self.build_commit
@@ -40,6 +44,10 @@ module Crystal
       end
     end
 
+    def self.release_mode?
+      {{ flag?(:release) }}
+    end
+
     @@host_target : Crystal::Codegen::Target?
 
     def self.host_target : Crystal::Codegen::Target