diff --git a/Makefile b/Makefile
index abe1b11a2..282fe47f8 100644
--- a/Makefile
+++ b/Makefile
@@ -2,7 +2,7 @@ CC = clang
 CFLAGS = -w -O2 -march=native -mtune=native
 
 dev: install-production
-	time lm --v2 tests/promises/lm-ascript/ascript-integrated.lsts
+	time lm --v2 tests/promises/string/prefix.lsts
 	gcc tmp.c
 	./a.out
 
diff --git a/lib2/core/baremetal.lsts b/lib2/core/baremetal.lsts
index a87b31ad0..9a17ba9d6 100644
--- a/lib2/core/baremetal.lsts
+++ b/lib2/core/baremetal.lsts
@@ -28,5 +28,6 @@ import lib2/core/cstring.lsts;
 import lib2/core/array.lsts;
 import lib2/core/io.lsts;
 import lib2/core/cmp.lsts;
+import lib2/core/c_int.lsts;
 
 let config-v23 = true;
diff --git a/lib2/core/c_int.lsts b/lib2/core/c_int.lsts
new file mode 100644
index 000000000..d71a7d7f2
--- /dev/null
+++ b/lib2/core/c_int.lsts
@@ -0,0 +1,21 @@
+
+declare-binop( $"!=", raw-type(C<"int">), raw-type(C<"int">), raw-type(Bool), ( l"("; x; l"!="; y; l")"; ) );
+declare-binop( $"==", raw-type(C<"int">), raw-type(C<"int">), raw-type(Bool), ( l"("; x; l"=="; y; l")"; ) );
+declare-binop( $"<",  raw-type(C<"int">), raw-type(C<"int">), raw-type(Bool), ( l"("; x; l"<"; y; l")"; ) );
+declare-binop( $"<=", raw-type(C<"int">), raw-type(C<"int">), raw-type(Bool), ( l"("; x; l"<="; y; l")"; ) );
+declare-binop( $">",  raw-type(C<"int">), raw-type(C<"int">), raw-type(Bool), ( l"("; x; l">"; y; l")"; ) );
+declare-binop( $">=", raw-type(C<"int">), raw-type(C<"int">), raw-type(Bool), ( l"("; x; l">="; y; l")"; ) );
+
+declare-binop( $"&", raw-type(C<"int">), raw-type(C<"int">), raw-type(C<"int">), ( l"("; x; l"&"; y; l")"; ) );
+declare-binop( $"|", raw-type(C<"int">), raw-type(C<"int">), raw-type(C<"int">), ( l"("; x; l"|"; y; l")"; ) );
+declare-binop( $"^", raw-type(C<"int">), raw-type(C<"int">), raw-type(C<"int">), ( l"("; x; l"^"; y; l")"; ) );
+declare-binop( $"+", raw-type(C<"int">), raw-type(C<"int">), raw-type(C<"int">), ( l"("; x; l"+"; y; l")"; ) );
+declare-binop( $"-", raw-type(C<"int">), raw-type(C<"int">), raw-type(C<"int">), ( l"("; x; l"-"; y; l")"; ) );
+declare-binop( $"/", raw-type(C<"int">), raw-type(C<"int">), raw-type(C<"int">), ( l"("; x; l"/"; y; l")"; ) );
+declare-binop( $"%", raw-type(C<"int">), raw-type(C<"int">), raw-type(C<"int">), ( l"("; x; l"%"; y; l")"; ) );
+declare-binop( $"*", raw-type(C<"int">), raw-type(C<"int">), raw-type(C<"int">), ( l"("; x; l"*"; y; l")"; ) );
+
+declare-binop( $"<<", raw-type(C<"int">), raw-type(C<"int">), raw-type(C<"int">), ( l"("; x; l"<<"; y; l")"; ) );
+declare-binop( $">>", raw-type(C<"int">), raw-type(C<"int">), raw-type(C<"int">), ( l"("; x; l">>"; y; l")"; ) );
+
+declare-unop( $"~", raw-type(C<"int">), raw-type(C<"int">), ( l"((uint64_t)(~"; x; l"))"; ) );
diff --git a/lib2/core/platform-macros.lsts b/lib2/core/platform-macros.lsts
index 646a267b1..00f02f87c 100644
--- a/lib2/core/platform-macros.lsts
+++ b/lib2/core/platform-macros.lsts
@@ -1,4 +1,10 @@
 
+deprecated macro (rl"declare-zop"(op-alias, r-type, op-expr)) (
+   let :Blob op-alias(): r-type = (
+      $":expression"(op-expr);
+   );
+);
+
 deprecated macro (rl"declare-unop"(op-alias, x-type, r-type, op-expr)) (
    let :Blob op-alias(x: x-type): r-type = (
       $":expression"(op-expr);
diff --git a/lib2/core/regex.lsts b/lib2/core/regex.lsts
index 16fc02cb5..0fcd4a5d1 100644
--- a/lib2/core/regex.lsts
+++ b/lib2/core/regex.lsts
@@ -10,22 +10,33 @@ let :Blob .rm_eo(t: C<"regmatch_t">): U64 = (
    $":expression"( l"("; $":expression"(t); l".rm_eo)"; );
 );
 
+declare-binop( $"set.rm_so", raw-type(C<"regmatch_t">), raw-type(U64), raw-type(Nil), ( l"("; x; l".rm_so="; y;  l")"; ) );
+declare-binop( $"set.rm_eo", raw-type(C<"regmatch_t">), raw-type(U64), raw-type(Nil), ( l"("; x; l".rm_eo="; y;  l")"; ) );
+
+declare-ternop( $"set.rm_so", raw-type(C<"regmatch_t">[]), raw-type(USize), raw-type(U64), raw-type(Nil), ( l"("; x; l"["; y; l"].rm_so="; z;  l")"; ) );
+declare-ternop( $"set.rm_eo", raw-type(C<"regmatch_t">[]), raw-type(USize), raw-type(U64), raw-type(Nil), ( l"("; x; l"["; y; l"].rm_eo="; z;  l")"; ) );
+
+declare-zop( $"reg_startend", raw-type(C<"int">), l"REG_STARTEND" );
+declare-zop( $"reg_nomatch", raw-type(C<"int">), l"REG_NOMATCH" );
+
 let .has-prefix(text: String, rgx: Regex): Bool = (
    # TODO: fix this mess. The preprocessor is unpacking these erroneously
    # macros 2.0 doesn't have this problem, but this code still needs to be updated after swapping
    let a1 = &rgx as C<"regex_t">[];
    let a2 = (text.data.data + text.start-offset) as C<"char">[];
    let a3 = 0 as C<"size_t">;
-   let a4 = 0 as C<"regmatch_t">[];
-   let a5 = 0 as C<"int">;
+   let a4 = () : C<"regmatch_t">[1];
+   a4[0].rm_so = 0;
+   a4[0].rm_eo = text.length;
+   let a5 = reg_startend();
    let status = regexec(
       a1,
       a2,
       a3,
-      a4,
+      a4 as C<"regmatch_t">[],
       a5
    );
-   (status as U64) == 0
+   status != reg_nomatch() and a4[0].rm_so==0
 );
 
 let $"=="(text: CString, rgx: Regex): Bool = (
@@ -42,16 +53,18 @@ let $"=="(text: CString, rgx: Regex): Bool = (
       a4,
       a5
    );
-   (status as U64)==0 and matches[0].rm_so==0 and matches[0].rm_eo==text.length
+   status != reg_nomatch() and matches[0].rm_so==0 and matches[0].rm_eo==text.length
 );
 
 let .remove-prefix(text: String, rgx: Regex): String? = (
    let matches = () : C<"regmatch_t">[1];
+   matches[0].rm_so = 0;
+   matches[0].rm_eo = text.length;
    let a1 = &rgx as C<"regex_t">[];
    let a2 = (text.data.data + text.start-offset) as C<"char">[];
    let a3 = 1 as C<"size_t">;
    let a4 = matches as C<"regmatch_t">[];
-   let a5 = 0 as C<"int">;
+   let a5 = reg_startend();
    let status = regexec(
       a1,
       a2,
@@ -59,18 +72,21 @@ let .remove-prefix(text: String, rgx: Regex): String? = (
       a4,
       a5
    );
-   if matches[0].rm_so != 0 then (None : String?)
+   if status == reg_nomatch() then (None : String?)
+   else if matches[0].rm_so != 0 then (None : String?)
    else if matches[0].rm_eo == 0 then (None : String?)
-   else Some(text[matches[0].rm_eo as I64 : ])
+   else Some(text[matches[0].rm_eo as I64 : ]);
 );
 
 let .get-prefix(text: String, rgx: Regex): String? = (
    let matches = () : C<"regmatch_t">[1];
+   matches[0].rm_so = 0;
+   matches[0].rm_eo = text.length;
    let a1 = &rgx as C<"regex_t">[];
    let a2 = (text.data.data + text.start-offset) as C<"char">[];
    let a3 = 1 as C<"size_t">;
    let a4 = matches as C<"regmatch_t">[];
-   let a5 = 0 as C<"int">;
+   let a5 = reg_startend();
    let status = regexec(
       a1,
       a2,
@@ -78,7 +94,8 @@ let .get-prefix(text: String, rgx: Regex): String? = (
       a4,
       a5
    );
-   if matches[0].rm_so != 0 then (None : String?)
+   if status == reg_nomatch() then (None : String?)
+   else if matches[0].rm_so != 0 then (None : String?)
    else if matches[0].rm_eo == 0 then (None : String?)
    else Some(text[0_i64 : matches[0].rm_eo as I64])
 );
diff --git a/tests/promises/string/prefix.lsts b/tests/promises/string/prefix.lsts
index 650ebf055..107ed4dcc 100644
--- a/tests/promises/string/prefix.lsts
+++ b/tests/promises/string/prefix.lsts
@@ -30,3 +30,6 @@ assert( " ".remove-prefix(r/^[a-zA-Z0-9_-]+/) == (None : String?) );
 
 assert( " import "[1_u64:].remove-prefix(r/^[a-zA-Z0-9_-]+/) == Some(" ") );
 assert( "  "[1_u64:].remove-prefix(r/^[a-zA-Z0-9_-]+/) == (None : String?) );
+
+assert( "ORANGEAPPLE"[:6_u64].remove-prefix(r/APPLE/) == (None : String?) );
+assert( not("ORANGEAPPLE"[:6_u64].has-prefix(r/APPLE/)) );