diff --git a/.gitignore b/.gitignore
index b4bcb39..1fcd342 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,3 +3,4 @@ _build/
 *~
 src/tz_index.erl
 *.sw?
+rebar3
diff --git a/Makefile b/Makefile
index 7ddd15e..152df64 100644
--- a/Makefile
+++ b/Makefile
@@ -1,11 +1,26 @@
-all:
+all: rebar3
 	./rebar3 compile
 
-check:
+check: rebar3
 	./rebar3 eunit
 
-dialyzer:
+test: check
+
+dialyzer: rebar3
 	./rebar3 dialyzer
 
-publish:
+publish: rebar3
 	./rebar3 hex publish
+
+rebar3:
+	@(echo "Building rebar3...")
+	@(rm -fr tmp)
+	@(mkdir -p tmp)
+	@(cd tmp && \
+		git clone https://github.com/erlang/rebar3 && \
+		cd rebar3 && \
+		./bootstrap)
+	@(echo "Moving rebar3 executable locally (NOT installing system-wide)")
+	@(mv tmp/rebar3/rebar3 .)
+	@(echo "Cleaning up rebar3 remnants")
+	@(rm -fr tmp)
diff --git a/README.md b/README.md
index 19144ca..6e69541 100644
--- a/README.md
+++ b/README.md
@@ -1,21 +1,21 @@
 ## NOTE
 
-This is a fork of
-[erlang_localtime](https://github.com/dmitryme/erlang_localtime), modified
-specifically for compatibility with
+This is a fork of the excellent library,
+[erlang_localtime](https://github.com/dmitryme/erlang_localtime). The purpose
+of this fork is specifically for compatibility with
 [qdate](https://github.com/choptastic/qdate).  The two are mostly compatible,
-but have diverged a bit over the years.  The qdate tests will not pass if the
-original erlang_localtime dependency is used due to some subtle differences to
-attempt to make qdate a little bit smarter.
+but have diverged slightly over the years.  The qdate tests will not pass if the
+original `erlang_localtime dependency` is used due to some subtle differences
+to attempt to make qdate a little bit smarter.
 
 #### Public exports
 
-* utc_to_local(DateTime, Timezone) - converts UTC time to local according to specified Timezone
-* local_to_utc(DateTime, Timezone) - converts local time to UTC
-* local_to_local(DateTime, TimezoneFrom, TimezoneTo) - converts local time to local
-* tz_name(DateTime, Timezone) - returns a timezone name (E.g. MSK, MSD, etc)
-* tz_shift(DateTime, Timezone) - returns time difference between local datetime and GMT
-* tz_shift(DateTime, TimezoneFrom, TimezoneTo) - returns time difference between local datetime and required timezone
+* `utc_to_local(DateTime, Timezone)` - converts UTC time to local according to specified Timezone
+* `local_to_utc(DateTime, Timezone)` - converts local time to UTC
+* `local_to_local(DateTime, TimezoneFrom, TimezoneTo)` - converts local time to local
+* `tz_name(DateTime, Timezone)` - returns a timezone name (E.g. MSK, MSD, etc)
+* `tz_shift(DateTime, Timezone)` - returns time difference between local datetime and GMT
+* `tz_shift(DateTime, TimezoneFrom, TimezoneTo)` - returns time difference between local datetime and required timezone
 Where
 DateTime = {date(), time()}
 TimeZone(To, From) = String(). E.g. “Europe/Moscow”, “America/NewYork”. Or abbreviations "MSK", "MSD", etc. Note:
diff --git a/include/tz_database.hrl b/include/tz_database.hrl
index 4cfd583..bbde520 100644
--- a/include/tz_database.hrl
+++ b/include/tz_database.hrl
@@ -35,7 +35,7 @@
       %%   Discarded excess rules for Zone Africa/El_Aaiun.
       %%   Moving rule to beginning of day for Zone America/Godthab.
       %%   Moving rule to beginning of day for Zone America/Godthab.
-      %%   Rounded timezone rules of Asia/Tehran to week 3 in march and september
+      %%   Removed DST from Iran and Asia/Tehran
 
       {"Africa/Abidjan",{"GMT","GMT"},undef,0,0,undef,{0,0},undef,{0,0}},
       {"Africa/Accra",{"GMT","GMT"},undef,0,0,undef,{0,0},undef,{0,0}},
@@ -347,7 +347,7 @@
       {"Asia/Taipei",{"CST","CST"},undef,480,0,undef,{0,0},undef,{0,0}},
       {"Asia/Tashkent",{"UZT","UZT"},undef,300,0,undef,{0,0},undef,{0,0}},
       {"Asia/Tbilisi",{"GET","GET"},undef,240,0,undef,{0,0},undef,{0,0}},
-      {"Asia/Tehran",{"IRST","IRST"},{"IRDT","IRDT"},210,60,{3,sat,mar},{0,0},{3,sat,sep},{0,0}},
+      {"Asia/Tehran",{"IRST","IRST"},undef,210,0,undef,{0,0},undef,{0,0}},
       {"Asia/Tel_Aviv",{"IST","IST"},{"IDT","IDT"},120,60,{4,fri,mar},{2,0},{last,sun,oct},{2,0}},
       {"Asia/Thimbu",{"BTT","BTT"},undef,360,0,undef,{0,0},undef,{0,0}},
       {"Asia/Thimphu",{"BTT","BTT"},undef,360,0,undef,{0,0},undef,{0,0}},
@@ -535,7 +535,7 @@
       {"Indian/Mauritius",{"MUT","MUT"},undef,240,0,undef,{0,0},undef,{0,0}},
       {"Indian/Mayotte",{"EAT","EAT"},undef,180,0,undef,{0,0},undef,{0,0}},
       {"Indian/Reunion",{"RET","RET"},undef,240,0,undef,{0,0},undef,{0,0}},
-      {"Iran",{"IRST","IRST"},{"IRDT","IRDT"},210,60,undef,{0,0},undef,{0,0}},
+      {"Iran",{"IRST","IRST"},undef,210,0,undef,{0,0},undef,{0,0}},
       {"Israel",{"IST","IST"},{"IDT","IDT"},120,60,{4,fri,mar},{2,0},{last,sun,oct},{2,0}},
       {"Jamaica",{"EST","EST"},undef,-300,0,undef,{0,0},undef,{0,0}},
       {"Japan",{"JST","JST"},undef,540,0,undef,{0,0},undef,{0,0}},
diff --git a/priv/db/.gitignore b/priv/db/.gitignore
new file mode 100644
index 0000000..badaa65
--- /dev/null
+++ b/priv/db/.gitignore
@@ -0,0 +1,3 @@
+tzout
+tzdata/
+*.tar.gz
diff --git a/db/Makefile b/priv/db/Makefile
similarity index 82%
rename from db/Makefile
rename to priv/db/Makefile
index 44071f0..dc2cb42 100644
--- a/db/Makefile
+++ b/priv/db/Makefile
@@ -3,7 +3,7 @@ TZ_FILES=$(addprefix $(TZDIR)/, africa antarctica asia australasia backward etce
 
 tzout: DATE := $(shell date +%F)
 tzout: $(TZ_FILES)
-	TZ_VERSION=`perl -n -e 'm/^VERSION\s*=\s*(\S+)/ and print $$1;' $(TZDIR)/Makefile`; \
+	TZ_VERSION=`cat $(TZDIR)/version`; \
 	./tz-erl --version $$TZ_VERSION --date $(DATE) -o $@ $^
 
 $(TZ_FILES): $(TZDIR)
@@ -14,4 +14,5 @@ $(TZDIR): tzdata-latest.tar.gz
 tzdata-latest.tar.gz:
 	curl -O "ftp://ftp.iana.org/tz/tzdata-latest.tar.gz"
 
-
+clean:
+	@(rm -fr tzdata *.tar.gz tzout *~)
diff --git a/db/tz-erl b/priv/db/tz-erl
similarity index 95%
rename from db/tz-erl
rename to priv/db/tz-erl
index 3f41e21..bcc743e 100755
--- a/db/tz-erl
+++ b/priv/db/tz-erl
@@ -459,11 +459,16 @@ sub on_to_day_of_month {
   my $day;
   if ($on =~ m/^\d+$/) {
     $day = $on;
+	print "Day extracted via regex to: $day\n";
   } else {
     my ($desired_dow, $time_base);
     if ($on =~ m/^(\w+)>=(\d+)$/) {
       $desired_dow = $dow_from_name{$1}; my $desired_day = $2;
       $time_base = timelocal(0, 0, 0, $desired_day, $month, $year);
+	  print "Regex: $on => desired_dow: $desired_dow. Time_base: $time_base\n";
+    } elsif ($on =~ m/^(\w+)<=(\d+)$/) {
+	  $desired_dow = $dow_from_name{$1}; my $desired_day = $2;
+	  $time_base = timelocal(0, 0, 0, $desired_day, $month, $year);
     } elsif ($on =~ m/^last(\w+)$/) {
       $desired_dow = $dow_from_name{$1};
       # One week before the beginning of the next month.
@@ -472,7 +477,12 @@ sub on_to_day_of_month {
       die "match $on failed";
     }
     ($day, my $dow) = (localtime($time_base))[3,6];
-    if ($dow != $desired_dow) { $day += (DPW + $desired_dow - $dow) % DPW; }
+	print "Current Day: $day\n";
+	print "Comparing $dow = $desired_dow\n";
+    if ($dow != $desired_dow) {
+		$day += (DPW + $desired_dow - $dow) % DPW;
+	}
+	print "After comparison: Current Day: $day\n";
   }
 
   return $day;
@@ -511,6 +521,10 @@ sub last_active_epoch {
   }
 
   my $day = on_to_day_of_month($on, $year, $month);
+  print "On=$on, Year=$year, Month=$month ====> Day=$day\n";
+  ## changing the below call to timelocal_nocheck stops the crash, but it feels wrong
+  ## especially since without it, it seems to produce a lot of "redundant" error messages
+  ## I don't have time to explore this now, but I'll come back to it
   return timelocal(0, 0, 0, $day, $month, $year);
 }
 
diff --git a/rebar.config b/rebar.config
index 1aad9de..781bcf2 100644
--- a/rebar.config
+++ b/rebar.config
@@ -6,6 +6,6 @@
 
 {pre_hooks,[
         {"linux|bsd|darwin|solaris", compile, "priv/ibuild.escript"},
-        {"win32", compile, "escript.exe priv\\ibuild.escript"}
+        {"win32", compile, "escript.exe priv/ibuild.escript"}
 ]}.
 
diff --git a/rebar.lock b/rebar.lock
deleted file mode 100644
index 57afcca..0000000
--- a/rebar.lock
+++ /dev/null
@@ -1 +0,0 @@
-[].
diff --git a/rebar3 b/rebar3
deleted file mode 100755
index 6f0ccfa..0000000
Binary files a/rebar3 and /dev/null differ
diff --git a/src/localtime.erl b/src/localtime.erl
index 1cbcf94..0bf952a 100644
--- a/src/localtime.erl
+++ b/src/localtime.erl
@@ -255,10 +255,12 @@ tr_char_test() ->
    ?assertEqual("A_C_E", tr_char("A C E", ?SPACE_CHAR, $_)).
 
 tz_name_test() ->
-    ?assertEqual({"CET", "CET"}, tz_name({{2008,12,10},{15,30,0}}, "Europe/Amsterdam")),
-    ?assertEqual({"IRST", "IRST"}, tz_name({{2008,12,10},{15,30,0}}, "Asia/Tehran")),
-    ?assertEqual({"IRDT", "IRDT"}, tz_name({{2020,5,4},{15,30,0}}, "Asia/Tehran")).
-
+   ?assertEqual({"CET", "CET"}, tz_name({{2008,12,10},{15,30,0}}, "Europe/Amsterdam")),
+   %%% No DST in Iran
+   ?assertEqual({"IRST", "IRST"}, tz_name({{2008,12,10},{15,30,0}}, "Asia/Tehran")),
+   ?assertEqual({"IRST", "IRST"}, tz_name({{2020,5,4},{15,30,0}}, "Asia/Tehran")),
+   ?assertEqual({"IRST", "IRST"}, tz_name({{2008,12,10},{15,30,0}}, "Iran")),
+   ?assertEqual({"IRST", "IRST"}, tz_name({{2020,5,4},{15,30,0}}, "Iran")).
 
 get_timezone_test() ->
    ?assertEqual("America/Los_Angeles", get_timezone("America/Los Angeles")).
diff --git a/src/qdate_localtime.app.src b/src/qdate_localtime.app.src
index 1f5e01f..a7d9093 100644
--- a/src/qdate_localtime.app.src
+++ b/src/qdate_localtime.app.src
@@ -1,7 +1,7 @@
 {application, 'qdate_localtime',
  [
   {description, "Erlang library for conversion from one local time to another (forked specifically for qdate compatibility)"},
-  {vsn, "1.2.0"},
+  {vsn, "1.2.1"},
   {applications, [kernel, stdlib]},
   {modules, []},
   {registered, []},