diff --git a/spec/generate_interpreter_spec.sh b/spec/generate_interpreter_spec.sh
index f3500115a737..960ab37f48db 100755
--- a/spec/generate_interpreter_spec.sh
+++ b/spec/generate_interpreter_spec.sh
@@ -19,7 +19,7 @@ echo "# $(date --rfc-3339 seconds) This file is autogenerated by \`${command% }\
 run_spec () {
   spec=$1
   require="require \"./${spec##spec/}\""
-  timeout 150 $CRYSTAL_BIN i $spec > /dev/null; exit=$?
+  timeout --signal=KILL 150 $CRYSTAL_BIN i $spec > /dev/null; exit=$?
 
   if [ $exit -eq 0 ] ; then
     echo "$require" >> $OUT_FILE
diff --git a/spec/interpreter_std_spec.cr b/spec/interpreter_std_spec.cr
index 79b8bab3edbc..0bb16eeeb2a1 100644
--- a/spec/interpreter_std_spec.cr
+++ b/spec/interpreter_std_spec.cr
@@ -1,4 +1,4 @@
-# 2023-04-12 22:54:02-05:00 This file is autogenerated by `spec/generate_interpreter_spec.sh std spec/interpreter_std_spec.cr`
+# 2024-03-22 14:01:27+08:00 This file is autogenerated by `./spec/generate_interpreter_spec.sh std spec/interpreter_std_spec.cr 8`
 require "./std/array_spec.cr"
 require "./std/atomic_spec.cr"
 require "./std/base64_spec.cr"
@@ -50,6 +50,7 @@ require "./std/crystal/hasher_spec.cr"
 require "./std/crystal/pointer_linked_list_spec.cr"
 require "./std/crystal/syntax_highlighter/colorize_spec.cr"
 require "./std/crystal/syntax_highlighter/html_spec.cr"
+require "./std/crystal/system_spec.cr"
 require "./std/csv/csv_build_spec.cr"
 require "./std/csv/csv_lex_spec.cr"
 require "./std/csv/csv_parse_spec.cr"
@@ -62,7 +63,7 @@ require "./std/digest/md5_spec.cr"
 require "./std/digest/sha1_spec.cr"
 require "./std/digest/sha256_spec.cr"
 require "./std/digest/sha512_spec.cr"
-# require "./std/dir_spec.cr" (failed to run)
+require "./std/dir_spec.cr"
 require "./std/double_spec.cr"
 require "./std/ecr/ecr_lexer_spec.cr"
 require "./std/ecr/ecr_spec.cr"
@@ -70,8 +71,8 @@ require "./std/enumerable_spec.cr"
 require "./std/enum_spec.cr"
 require "./std/env_spec.cr"
 require "./std/errno_spec.cr"
-# require "./std/exception/call_stack_spec.cr" (failed to run)
-# require "./std/exception_spec.cr" (failed to run)
+require "./std/exception/call_stack_spec.cr"
+require "./std/exception_spec.cr"
 require "./std/fiber_spec.cr"
 require "./std/file_spec.cr"
 require "./std/file/tempfile_spec.cr"
@@ -80,6 +81,7 @@ require "./std/float_printer/diy_fp_spec.cr"
 require "./std/float_printer/grisu3_spec.cr"
 require "./std/float_printer/hexfloat_spec.cr"
 require "./std/float_printer/ieee_spec.cr"
+require "./std/float_printer/ryu_printf_spec.cr"
 require "./std/float_printer/shortest_spec.cr"
 require "./std/float_spec.cr"
 require "./std/gc_spec.cr"
@@ -116,7 +118,7 @@ require "./std/io/argf_spec.cr"
 require "./std/io/buffered_spec.cr"
 require "./std/io/byte_format_spec.cr"
 require "./std/io/delimited_spec.cr"
-# require "./std/io/file_descriptor_spec.cr" (failed to run)
+require "./std/io/file_descriptor_spec.cr"
 require "./std/io/hexdump_spec.cr"
 require "./std/io/io_spec.cr"
 require "./std/io/memory_spec.cr"
@@ -131,7 +133,7 @@ require "./std/json/parser_spec.cr"
 require "./std/json/pull_parser_spec.cr"
 require "./std/json/serializable_spec.cr"
 require "./std/json/serialization_spec.cr"
-# require "./std/kernel_spec.cr" (failed to run)
+require "./std/kernel_spec.cr"
 require "./std/levenshtein_spec.cr"
 # require "./std/llvm/aarch64_spec.cr" (failed to run)
 # require "./std/llvm/arm_abi_spec.cr" (failed to run)
@@ -185,7 +187,7 @@ require "./std/pointer_spec.cr"
 require "./std/pp_spec.cr"
 require "./std/pretty_print_spec.cr"
 require "./std/process/find_executable_spec.cr"
-# require "./std/process_spec.cr" (failed to run)
+require "./std/process_spec.cr"
 require "./std/process/status_spec.cr"
 require "./std/process/utils_spec.cr"
 require "./std/proc_spec.cr"
@@ -201,7 +203,7 @@ require "./std/regex/match_data_spec.cr"
 require "./std/regex_spec.cr"
 require "./std/semantic_version_spec.cr"
 require "./std/set_spec.cr"
-# require "./std/signal_spec.cr" (failed to run)
+require "./std/signal_spec.cr"
 require "./std/slice_spec.cr"
 require "./std/socket/address_spec.cr"
 require "./std/socket/addrinfo_spec.cr"
@@ -215,8 +217,9 @@ require "./std/spec/context_spec.cr"
 require "./std/spec/expectations_spec.cr"
 require "./std/spec/filters_spec.cr"
 require "./std/spec/helpers/iterate_spec.cr"
-# require "./std/spec/hooks_spec.cr" (failed to run)
+require "./std/spec/hooks_spec.cr"
 require "./std/spec/junit_formatter_spec.cr"
+require "./std/spec/list_tags_spec.cr"
 require "./std/spec_spec.cr"
 require "./std/spec/tap_formatter_spec.cr"
 require "./std/sprintf_spec.cr"
@@ -233,16 +236,16 @@ require "./std/symbol_spec.cr"
 # require "./std/syscall_spec.cr" (failed to run)
 require "./std/system_error_spec.cr"
 require "./std/system/group_spec.cr"
-# require "./std/system_spec.cr" (failed to run)
+require "./std/system_spec.cr"
 require "./std/system/user_spec.cr"
-# require "./std/thread/condition_variable_spec.cr" (interpreter must support threads)
-# require "./std/thread/mutex_spec.cr" (interpreter must support threads)
-# require "./std/thread_spec.cr" (interpreter must support threads)
+require "./std/thread/condition_variable_spec.cr"
+require "./std/thread/mutex_spec.cr"
+require "./std/thread_spec.cr"
 require "./std/time/custom_formats_spec.cr"
-require "./std/time/format_spec.cr"
+# require "./std/time/format_spec.cr" (failed to run)
 require "./std/time/location_spec.cr"
 require "./std/time/span_spec.cr"
-require "./std/time/time_spec.cr"
+# require "./std/time/time_spec.cr" (failed to run)
 require "./std/tuple_spec.cr"
 require "./std/uint_spec.cr"
 require "./std/uri/params_spec.cr"
@@ -251,7 +254,7 @@ require "./std/uri_spec.cr"
 require "./std/uuid/json_spec.cr"
 require "./std/uuid_spec.cr"
 require "./std/uuid/yaml_spec.cr"
-# require "./std/va_list_spec.cr" (failed to run)
+require "./std/va_list_spec.cr"
 require "./std/weak_ref_spec.cr"
 require "./std/winerror_spec.cr"
 require "./std/xml/builder_spec.cr"
diff --git a/spec/std/crystal/system_spec.cr b/spec/std/crystal/system_spec.cr
index 06bc789055d4..8e710f860a53 100644
--- a/spec/std/crystal/system_spec.cr
+++ b/spec/std/crystal/system_spec.cr
@@ -1,4 +1,4 @@
-require "spec"
+require "../spec_helper"
 
 private def print_error_to_s(format, *args)
   io = IO::Memory.new
@@ -26,7 +26,8 @@ describe "Crystal::System" do
       print_error_to_s("%x,%x,%x,%x,%x", 0, 0x1234, UInt32::MAX, Int32::MIN, UInt64::MAX).should eq("0,1234,ffffffff,80000000,ffffffff")
     end
 
-    it "supports %p" do
+    # TODO: investigate why this prints `(???)`
+    pending_interpreted "supports %p" do
       print_error_to_s("%p,%p,%p", Pointer(Void).new(0x0), Pointer(Void).new(0x1234), Pointer(Void).new(UInt64::MAX)).should eq("0x0,0x1234,0xffffffffffffffff")
     end
 
@@ -34,7 +35,8 @@ describe "Crystal::System" do
       print_error_to_s("%s,%s,%s", "abc\0def", "ghi".to_unsafe, Pointer(UInt8).null).should eq("abc\0def,ghi,(null)")
     end
 
-    it "supports %l width" do
+    # BUG: missing downcast_distinct from Tuple(Int64 | UInt64, Int64 | UInt64, Int64 | UInt64, Int64 | UInt64) to Tuple(Int64, Int64, Int64, Int64)
+    pending_interpreted "supports %l width" do
       values = {LibC::Long::MIN, LibC::Long::MAX, LibC::LongLong::MIN, LibC::LongLong::MAX}
       print_error_to_s("%ld,%ld,%lld,%lld", *values).should eq(values.join(','))
 
diff --git a/spec/std/dir_spec.cr b/spec/std/dir_spec.cr
index c2d86eff7bb2..439da15becd9 100644
--- a/spec/std/dir_spec.cr
+++ b/spec/std/dir_spec.cr
@@ -631,7 +631,8 @@ describe "Dir" do
   end
 
   describe ".current" do
-    it "matches shell" do
+    # can't use backtick in interpreted code (#12241)
+    pending_interpreted "matches shell" do
       Dir.current.should eq(`#{{{ flag?(:win32) ? "cmd /c cd" : "pwd" }}}`.chomp)
     end
 
diff --git a/spec/std/file_spec.cr b/spec/std/file_spec.cr
index 1e9a9f53ae32..fedbf0889370 100644
--- a/spec/std/file_spec.cr
+++ b/spec/std/file_spec.cr
@@ -79,10 +79,9 @@ describe "File" do
         end
       end
 
-      {% if LibC.has_method?(:mkfifo) && !flag?(:interpreted) %}
-        # spec is disabled when interpreted because the interpreter doesn't
-        # support threads
-        it "opens fifo file as non-blocking" do
+      {% if LibC.has_method?(:mkfifo) %}
+        # interpreter doesn't support threads yet (#14287)
+        pending_interpreted "opens fifo file as non-blocking" do
           path = File.tempname("chardev")
           ret = LibC.mkfifo(path, File::DEFAULT_CREATE_PERMISSIONS)
           raise RuntimeError.from_errno("mkfifo") unless ret == 0
diff --git a/spec/std/file_utils_spec.cr b/spec/std/file_utils_spec.cr
index bc730dde5c01..87591120ff7b 100644
--- a/spec/std/file_utils_spec.cr
+++ b/spec/std/file_utils_spec.cr
@@ -715,9 +715,9 @@ describe "FileUtils" do
       end
     end
 
-    # FIXME: `Process.run` and backtick don't work in the interpreter (#12241)
-    {% if flag?(:unix) && !flag?(:interpreted) %}
-      it "overwrites a destination named pipe" do
+    {% if flag?(:unix) %}
+      # can't use backtick in interpreted code (#12241)
+      pending_interpreted "overwrites a destination named pipe" do
         with_tempfile("ln_sf_src", "ln_sf_dst_pipe_exists") do |path1, path2|
           test_with_string_and_path(path1, path2) do |arg1, arg2|
             FileUtils.touch([path1])
diff --git a/spec/std/process_spec.cr b/spec/std/process_spec.cr
index db3a058a7c44..6388b88fb70c 100644
--- a/spec/std/process_spec.cr
+++ b/spec/std/process_spec.cr
@@ -54,7 +54,8 @@ private def newline
   {% end %}
 end
 
-describe Process do
+# interpreted code doesn't receive SIGCHLD for `#wait` to work (#12241)
+pending_interpreted describe: Process do
   describe ".new" do
     it "raises if command doesn't exist" do
       expect_raises(File::NotFoundError, "Error executing process: 'foobarbaz'") do
diff --git a/spec/std/signal_spec.cr b/spec/std/signal_spec.cr
index d1d3aa3f1643..cae1c5e83834 100644
--- a/spec/std/signal_spec.cr
+++ b/spec/std/signal_spec.cr
@@ -1,9 +1,10 @@
 {% skip_file if flag?(:wasm32) %}
 
-require "spec"
+require "./spec_helper"
 require "signal"
 
-describe "Signal" do
+# interpreted code never receives signals (#12241)
+pending_interpreted describe: "Signal" do
   typeof(Signal::ABRT.reset)
   typeof(Signal::ABRT.ignore)
   typeof(Signal::ABRT.trap { 1 })
diff --git a/spec/std/spec_helper.cr b/spec/std/spec_helper.cr
index 18deaf0260bf..69c80968b117 100644
--- a/spec/std/spec_helper.cr
+++ b/spec/std/spec_helper.cr
@@ -3,6 +3,7 @@ require "../support/tempfile"
 require "../support/fibers"
 require "../support/win32"
 require "../support/wasm32"
+require "../support/interpreted"
 
 def datapath(*components)
   File.join("spec", "std", "data", *components)
@@ -77,6 +78,9 @@ def spawn_and_check(before : Proc(_), file = __FILE__, line = __LINE__, &block :
 end
 
 def compile_file(source_file, *, bin_name = "executable_file", flags = %w(), file = __FILE__, &)
+  # can't use backtick in interpreted code (#12241)
+  pending_interpreted! "Unable to compile Crystal code in interpreted code"
+
   with_temp_executable(bin_name, file: file) do |executable_file|
     compiler = ENV["CRYSTAL_SPEC_COMPILER_BIN"]? || "bin/crystal"
     args = ["build"] + flags + ["-o", executable_file, source_file]
diff --git a/spec/std/system_spec.cr b/spec/std/system_spec.cr
index 7a87b1a238c8..58023f0c0e59 100644
--- a/spec/std/system_spec.cr
+++ b/spec/std/system_spec.cr
@@ -3,7 +3,8 @@ require "system"
 
 describe System do
   describe "hostname" do
-    it "returns current hostname" do
+    # can't use backtick in interpreted code (#12241)
+    pending_interpreted "returns current hostname" do
       shell_hostname = `hostname`.strip
       pending! "`hostname` command was unsuccessful" unless $?.success?
 
@@ -13,7 +14,8 @@ describe System do
   end
 
   describe "cpu_count" do
-    it "returns current CPU count" do
+    # can't use backtick in interpreted code (#12241)
+    pending_interpreted "returns current CPU count" do
       shell_cpus =
         {% if flag?(:win32) %}
           ENV["NUMBER_OF_PROCESSORS"].to_i
diff --git a/spec/std/thread/condition_variable_spec.cr b/spec/std/thread/condition_variable_spec.cr
index 36e1963794b3..ff9c44204bb6 100644
--- a/spec/std/thread/condition_variable_spec.cr
+++ b/spec/std/thread/condition_variable_spec.cr
@@ -6,9 +6,10 @@
   {% skip_file %}
 {% end %}
 
-require "spec"
+require "../spec_helper"
 
-describe Thread::ConditionVariable do
+# interpreter doesn't support threads yet (#14287)
+pending_interpreted describe: Thread::ConditionVariable do
   it "signals" do
     mutex = Thread::Mutex.new
     cond = Thread::ConditionVariable.new
diff --git a/spec/std/thread/mutex_spec.cr b/spec/std/thread/mutex_spec.cr
index d028ffdd8f8a..ff298f318329 100644
--- a/spec/std/thread/mutex_spec.cr
+++ b/spec/std/thread/mutex_spec.cr
@@ -6,9 +6,10 @@
   {% skip_file %}
 {% end %}
 
-require "spec"
+require "../spec_helper"
 
-describe Thread::Mutex do
+# interpreter doesn't support threads yet (#14287)
+pending_interpreted describe: Thread::Mutex do
   it "synchronizes" do
     a = 0
     mutex = Thread::Mutex.new
diff --git a/spec/std/thread_spec.cr b/spec/std/thread_spec.cr
index 136026667137..feb55454b621 100644
--- a/spec/std/thread_spec.cr
+++ b/spec/std/thread_spec.cr
@@ -1,4 +1,4 @@
-require "spec"
+require "./spec_helper"
 
 {% if flag?(:musl) %}
   # FIXME: These thread specs occasionally fail on musl/alpine based ci, so
@@ -8,7 +8,8 @@ require "spec"
   {% skip_file %}
 {% end %}
 
-describe Thread do
+# interpreter doesn't support threads yet (#14287)
+pending_interpreted describe: Thread do
   it "allows passing an argumentless fun to execute" do
     a = 0
     thread = Thread.new { a = 1; 10 }
diff --git a/spec/support/interpreted.cr b/spec/support/interpreted.cr
new file mode 100644
index 000000000000..79f8a688c72b
--- /dev/null
+++ b/spec/support/interpreted.cr
@@ -0,0 +1,26 @@
+require "spec"
+
+{% if flag?(:interpreted) %}
+  def pending_interpreted(description = "assert", file = __FILE__, line = __LINE__, end_line = __END_LINE__, &block)
+    pending("#{description} [interpreted]", file, line, end_line)
+  end
+
+  def pending_interpreted(*, describe, file = __FILE__, line = __LINE__, end_line = __END_LINE__, &block)
+    pending_interpreted(describe, file, line, end_line) { }
+  end
+
+  def pending_interpreted!(msg = "Cannot run example", file = __FILE__, line = __LINE__)
+    pending!(msg, file, line)
+  end
+{% else %}
+  def pending_interpreted(description = "assert", file = __FILE__, line = __LINE__, end_line = __END_LINE__, &block)
+    it(description, file, line, end_line, &block)
+  end
+
+  def pending_interpreted(*, describe, file = __FILE__, line = __LINE__, end_line = __END_LINE__, &block)
+    describe(describe, file, line, end_line, &block)
+  end
+
+  def pending_interpreted!(msg = "Cannot run example", file = __FILE__, line = __LINE__)
+  end
+{% end %}
diff --git a/spec/support/tempfile.cr b/spec/support/tempfile.cr
index a5e0c57d010a..a77070d90e40 100644
--- a/spec/support/tempfile.cr
+++ b/spec/support/tempfile.cr
@@ -1,4 +1,5 @@
 require "file_utils"
+require "./interpreted"
 {% if flag?(:msvc) %}
   require "crystal/system/win32/visual_studio"
 {% end %}
@@ -47,6 +48,9 @@ def with_temp_executable(name, file = __FILE__, &)
 end
 
 def with_temp_c_object_file(c_code, *, filename = "temp_c", file = __FILE__, &)
+  # can't use backtick in interpreted code (#12241)
+  pending_interpreted! "Unable to compile C code in interpreted code"
+
   obj_ext = {{ flag?(:msvc) ? ".obj" : ".o" }}
   with_tempfile("#{filename}.c", "#{filename}#{obj_ext}", file: file) do |c_filename, o_filename|
     File.write(c_filename, c_code)