diff --git a/GNUmakefile.llvm b/GNUmakefile.llvm
index 65786d8b0e..0845ae3a20 100644
--- a/GNUmakefile.llvm
+++ b/GNUmakefile.llvm
@@ -46,7 +46,7 @@ LLVMVER  = $(shell $(LLVM_CONFIG) --version 2>/dev/null | sed 's/git//' | sed 's
 LLVM_MAJOR = $(shell $(LLVM_CONFIG) --version 2>/dev/null | sed 's/\..*//' )
 LLVM_MINOR = $(shell $(LLVM_CONFIG) --version 2>/dev/null | sed 's/.*\.//' | sed 's/git//' | sed 's/svn//' | sed 's/ .*//' )
 LLVM_UNSUPPORTED = $(shell $(LLVM_CONFIG) --version 2>/dev/null | grep -E -q '^[0-2]\.|^3.[0-7]\.' && echo 1 || echo 0 )
-LLVM_TOO_NEW = $(shell $(LLVM_CONFIG) --version 2>/dev/null | grep -E -q '^1[7-9]' && echo 1 || echo 0 )
+LLVM_TOO_NEW = $(shell $(LLVM_CONFIG) --version 2>/dev/null | grep -E -q '^1[8-9]|^2[0-9]' && echo 1 || echo 0 )
 LLVM_TOO_OLD = $(shell $(LLVM_CONFIG) --version 2>/dev/null | grep -E -q '^[1-9]\.|^1[012]\.' && echo 1 || echo 0 )
 LLVM_NEW_API = $(shell $(LLVM_CONFIG) --version 2>/dev/null | grep -E -q '^1[0-9]' && echo 1 || echo 0 )
 LLVM_NEWER_API = $(shell $(LLVM_CONFIG) --version 2>/dev/null | grep -E -q '^1[6-9]' && echo 1 || echo 0 )
diff --git a/TODO.md b/TODO.md
index ac24fe071b..9bdb2c5518 100644
--- a/TODO.md
+++ b/TODO.md
@@ -1,14 +1,19 @@
 # TODO list for AFL++
 
-## Should
+## Must
 
+ - adapt MOpt to new mutation engine
+ - Update afl->pending_not_fuzzed for MOpt
+ - cmplog rtn sanity check on fixed length? + no length 1
  - afl-showmap -f support
  - afl-fuzz multicore wrapper script
- - add value_profile but only enable after 15 minutes without finds
+
+## Should
+
+ - add value_profile but only enable after 15 minutes without finds?
  - afl-crash-analysis
  - support persistent and deferred fork server in afl-showmap?
  - better autodetection of shifting runtime timeout values
- - Update afl->pending_not_fuzzed for MOpt
  - afl-plot to support multiple plot_data
  - parallel builds for source-only targets
  - get rid of check_binary, replace with more forkserver communication
@@ -27,8 +32,7 @@ QEMU mode/FRIDA mode:
  - non colliding instrumentation
  - rename qemu specific envs to AFL_QEMU (AFL_ENTRYPOINT, AFL_CODE_START/END,
    AFL_COMPCOV_LEVEL?)
- - add AFL_QEMU_EXITPOINT (maybe multiple?), maybe pointless as there is
-   persistent mode
+ - add AFL_QEMU_EXITPOINT (maybe multiple?)
 
 ## Ideas
 
diff --git a/include/envs.h b/include/envs.h
index 4259d6ddd5..734b1707ae 100644
--- a/include/envs.h
+++ b/include/envs.h
@@ -179,6 +179,7 @@ static char *afl_environment_variables[] = {
     "AFL_NO_COLOUR",
 #endif
     "AFL_NO_CPU_RED",
+    "AFL_NO_CFG_FUZZING",  // afl.rs rust crate option
     "AFL_NO_CRASH_README",
     "AFL_NO_FORKSRV",
     "AFL_NO_UI",
diff --git a/include/forkserver.h b/include/forkserver.h
index 5e498c5635..f6230fe8c4 100644
--- a/include/forkserver.h
+++ b/include/forkserver.h
@@ -197,6 +197,7 @@ typedef struct afl_forkserver {
   u32                   nyx_id;          /* nyx runner id (0 -> master)      */
   u32                   nyx_bind_cpu_id; /* nyx runner cpu id                */
   char                 *nyx_aux_string;
+  u32                   nyx_aux_string_len;
   bool                  nyx_use_tmp_workdir;
   char                 *nyx_tmp_workdir_path;
   s32                   nyx_log_fd;
diff --git a/instrumentation/SanitizerCoveragePCGUARD.so.cc b/instrumentation/SanitizerCoveragePCGUARD.so.cc
index 98c5973cf9..588eb95057 100644
--- a/instrumentation/SanitizerCoveragePCGUARD.so.cc
+++ b/instrumentation/SanitizerCoveragePCGUARD.so.cc
@@ -214,7 +214,11 @@ llvmGetPassPluginInfo() {
 #if LLVM_VERSION_MAJOR == 13
             using OptimizationLevel = typename PassBuilder::OptimizationLevel;
 #endif
+#if LLVM_VERSION_MAJOR >= 16
+            PB.registerOptimizerEarlyEPCallback(
+#else
             PB.registerOptimizerLastEPCallback(
+#endif
                 [](ModulePassManager &MPM, OptimizationLevel OL) {
 
                   MPM.addPass(ModuleSanitizerCoverageAFL());
diff --git a/instrumentation/afl-compiler-rt.o.c b/instrumentation/afl-compiler-rt.o.c
index 85ee9f717d..c3197c8a34 100644
--- a/instrumentation/afl-compiler-rt.o.c
+++ b/instrumentation/afl-compiler-rt.o.c
@@ -666,6 +666,7 @@ static void __afl_map_shm(void) {
   }
 
   if (id_str) {
+
     // /dev/null doesn't work so we use /dev/urandom
     if ((__afl_dummy_fd[1] = open("/dev/urandom", O_WRONLY)) < 0) {
 
diff --git a/instrumentation/afl-llvm-pass.so.cc b/instrumentation/afl-llvm-pass.so.cc
index c59324fdfd..052488a9ab 100644
--- a/instrumentation/afl-llvm-pass.so.cc
+++ b/instrumentation/afl-llvm-pass.so.cc
@@ -552,7 +552,7 @@ bool AFLCoverage::runOnModule(Module &M) {
 #endif
         {
 
-          // load the context ID of the previous function and write to to a
+          // load the context ID of the previous function and write to a
           // local variable on the stack
           LoadInst *PrevCtxLoad = IRB.CreateLoad(
 #if LLVM_VERSION_MAJOR >= 14
@@ -634,7 +634,7 @@ bool AFLCoverage::runOnModule(Module &M) {
 
 /* There is a problem with Ubuntu 18.04 and llvm 6.0 (see issue #63).
    The inline function successors() is not inlined and also not found at runtime
-   :-( As I am unable to detect Ubuntu18.04 heree, the next best thing is to
+   :-( As I am unable to detect Ubuntu18.04 here, the next best thing is to
    disable this optional optimization for LLVM 6.0.0 and Linux */
 #if !(LLVM_VERSION_MAJOR == 6 && LLVM_VERSION_MINOR == 0) || !defined __linux__
       // only instrument if this basic block is the destination of a previous
diff --git a/src/afl-forkserver.c b/src/afl-forkserver.c
index 07f5a1a94b..9b710733ce 100644
--- a/src/afl-forkserver.c
+++ b/src/afl-forkserver.c
@@ -615,8 +615,10 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv,
 
     if (getenv("AFL_NYX_AUX_SIZE") != NULL) {
 
+      fsrv->nyx_aux_string_len = atoi(getenv("AFL_NYX_AUX_SIZE"));
+
       if (fsrv->nyx_handlers->nyx_config_set_aux_buffer_size(
-              nyx_config, atoi(getenv("AFL_NYX_AUX_SIZE"))) != 1) {
+              nyx_config, fsrv->nyx_aux_string_len) != 1) {
 
         NYX_PRE_FATAL(fsrv,
                       "Invalid AFL_NYX_AUX_SIZE value set (must be a multiple "
@@ -624,6 +626,10 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv,
 
       }
 
+    } else {
+
+      fsrv->nyx_aux_string_len = 0x1000;
+
     }
 
     if (getenv("AFL_NYX_REUSE_SNAPSHOT") != NULL) {
@@ -697,8 +703,8 @@ void afl_fsrv_start(afl_forkserver_t *fsrv, char **argv,
     fsrv->nyx_handlers->nyx_option_set_timeout(fsrv->nyx_runner, 2, 0);
     fsrv->nyx_handlers->nyx_option_apply(fsrv->nyx_runner);
 
-    fsrv->nyx_aux_string = malloc(0x1000);
-    memset(fsrv->nyx_aux_string, 0, 0x1000);
+    fsrv->nyx_aux_string = malloc(fsrv->nyx_aux_string_len);
+    memset(fsrv->nyx_aux_string, 0, fsrv->nyx_aux_string_len);
 
     /* dry run */
     fsrv->nyx_handlers->nyx_set_afl_input(fsrv->nyx_runner, "INIT", 4);
diff --git a/src/afl-fuzz-bitmap.c b/src/afl-fuzz-bitmap.c
index 0429db34ed..d76158ced5 100644
--- a/src/afl-fuzz-bitmap.c
+++ b/src/afl-fuzz-bitmap.c
@@ -866,7 +866,7 @@ save_if_interesting(afl_state_t *afl, void *mem, u32 len, u8 fault) {
     if (unlikely(fd < 0)) { PFATAL("Unable to create '%s'", fn_log); }
 
     u32 nyx_aux_string_len = afl->fsrv.nyx_handlers->nyx_get_aux_string(
-        afl->fsrv.nyx_runner, afl->fsrv.nyx_aux_string, 0x1000);
+        afl->fsrv.nyx_runner, afl->fsrv.nyx_aux_string, afl->fsrv.nyx_aux_string_len);
 
     ck_write(fd, afl->fsrv.nyx_aux_string, nyx_aux_string_len, fn_log);
     close(fd);
diff --git a/src/afl-fuzz-stats.c b/src/afl-fuzz-stats.c
index adf04420f6..66e32e78ed 100644
--- a/src/afl-fuzz-stats.c
+++ b/src/afl-fuzz-stats.c
@@ -250,11 +250,13 @@ void write_stats_file(afl_state_t *afl, u32 t_bytes, double bitmap_cvg,
 #endif
 
   u64   cur_time = get_cur_time();
-  u8    fn[PATH_MAX];
+  u8    fn_tmp[PATH_MAX];
+  u8    fn_final[PATH_MAX];
   FILE *f;
 
-  snprintf(fn, PATH_MAX, "%s/fuzzer_stats", afl->out_dir);
-  f = create_ffile(fn);
+  snprintf(fn_tmp, PATH_MAX, "%s/.fuzzer_stats_tmp", afl->out_dir);
+  snprintf(fn_final, PATH_MAX, "%s/fuzzer_stats", afl->out_dir);
+  f = create_ffile(fn_tmp);
 
   /* Keep last values in case we're called from another context
      where exec/sec stats and such are not readily available. */
@@ -412,6 +414,7 @@ void write_stats_file(afl_state_t *afl, u32 t_bytes, double bitmap_cvg,
   }
 
   fclose(f);
+  rename(fn_tmp, fn_final);
 
 }
 
@@ -817,17 +820,18 @@ void show_stats_normal(afl_state_t *afl) {
     if (afl->fsrv.nyx_mode) {
 
       snprintf(banner + banner_pad, sizeof(banner) - banner_pad,
-               "%s%s " cLCY VERSION cLBL " {%s} " cLGN "(%s) " cPIN "[%s] - Nyx",
-               afl->crash_mode ? cPIN : cYEL, fuzzer_name,
-               si, afl->use_banner, afl->power_name);
+               "%s%s " cLCY VERSION cLBL " {%s} " cLGN "(%s) " cPIN
+               "[%s] - Nyx",
+               afl->crash_mode ? cPIN : cYEL, fuzzer_name, si, afl->use_banner,
+               afl->power_name);
 
     } else {
 
 #endif
       snprintf(banner + banner_pad, sizeof(banner) - banner_pad,
                "%s%s " cLCY VERSION cLBL " {%s} " cLGN "(%s) " cPIN "[%s]",
-               afl->crash_mode ? cPIN : cYEL, fuzzer_name,
-               si, afl->use_banner, afl->power_name);
+               afl->crash_mode ? cPIN : cYEL, fuzzer_name, si, afl->use_banner,
+               afl->power_name);
 
 #ifdef __linux__
 
diff --git a/src/afl-fuzz-statsd.c b/src/afl-fuzz-statsd.c
index e835c8ea2f..2e42ea9b7f 100644
--- a/src/afl-fuzz-statsd.c
+++ b/src/afl-fuzz-statsd.c
@@ -223,7 +223,7 @@ int statsd_format_metric(afl_state_t *afl, char *buff, size_t bufflen) {
   char tags[MAX_TAG_LEN * 2] = {0};
   if (afl->statsd_tags_format) {
 
-    snprintf(tags, MAX_TAG_LEN * 2, afl->statsd_tags_format, afl->use_banner,
+    snprintf(tags, MAX_TAG_LEN * 2, afl->statsd_tags_format, afl->sync_id,
              VERSION);
 
   }
diff --git a/unicorn_mode/UNICORNAFL_VERSION b/unicorn_mode/UNICORNAFL_VERSION
index 1c8e571fc0..51878a56f3 100644
--- a/unicorn_mode/UNICORNAFL_VERSION
+++ b/unicorn_mode/UNICORNAFL_VERSION
@@ -1 +1 @@
-f2cede37
+f607118f
diff --git a/unicorn_mode/unicornafl b/unicorn_mode/unicornafl
index f2cede37a7..f607118fc1 160000
--- a/unicorn_mode/unicornafl
+++ b/unicorn_mode/unicornafl
@@ -1 +1 @@
-Subproject commit f2cede37a75bbd4a9b9438f0277727b5d4620572
+Subproject commit f607118fc10e5225da751385075792e24133a130