diff --git a/.gitignore b/.gitignore
index 9e5ec4e3f..30d8efb51 100644
--- a/.gitignore
+++ b/.gitignore
@@ -13,3 +13,4 @@ test/gen_KAT1024
 test/gen_NISTKAT512
 test/gen_NISTKAT768
 test/gen_NISTKAT1024
+*.dSYM
\ No newline at end of file
diff --git a/Makefile b/Makefile
index 583b271e4..2dfaa3ca8 100644
--- a/Makefile
+++ b/Makefile
@@ -13,12 +13,12 @@ CFLAGS_NISTRANDOMBYTES = ${CFLAGS} ${INCLUDE_NISTRANDOM}
 NISTFLAGS += -Wno-unused-result -O3 -fomit-frame-pointer
 RM = /bin/rm
 
-SOURCES = mlkem/kem.c mlkem/indcpa.c mlkem/polyvec.c mlkem/poly.c mlkem/ntt.c mlkem/cbd.c mlkem/reduce.c mlkem/verify.c
+SOURCES = mlkem/kem.c mlkem/indcpa.c mlkem/polyvec.c mlkem/poly.c mlkem/ntt.c mlkem/cbd.c mlkem/reduce.c mlkem/verify.c mlkem/rej_uniform.c mlkem/rej_uniform_asm.s
 SOURCESKECCAK = $(SOURCES) fips202/keccakf1600.c fips202/fips202.c mlkem/symmetric-shake.c
 SOURCESKECCAKRANDOM = $(SOURCESKECCAK) randombytes/randombytes.c
 SOURCESNISTKATS = $(SOURCESKECCAK) test/nistrng/aes.c test/nistrng/rng.c
 
-HEADERS = mlkem/params.h mlkem/kem.h mlkem/indcpa.h mlkem/polyvec.h mlkem/poly.h mlkem/ntt.h mlkem/cbd.h mlkem/reduce.c mlkem/verify.h mlkem/symmetric.h
+HEADERS = mlkem/params.h mlkem/kem.h mlkem/indcpa.h mlkem/polyvec.h mlkem/poly.h mlkem/ntt.h mlkem/cbd.h mlkem/reduce.c mlkem/verify.h mlkem/symmetric.h mlkem/rej_uniform.h
 HEADERSKECCAK = $(HEADERS) fips202/keccakf1600.h fips202/fips202.h
 HEADERSKECCAKRANDOM = $(HEADERSKECCAK) randombytes/randombytes.h
 HEADERNISTKATS = $(HEADERSKECCAK) test/nistrng/aes.h test/nistrng/randombytes.h
diff --git a/mlkem/indcpa.c b/mlkem/indcpa.c
index 648bc26cc..dd9d4783c 100644
--- a/mlkem/indcpa.c
+++ b/mlkem/indcpa.c
@@ -7,6 +7,7 @@
 #include "polyvec.h"
 #include "poly.h"
 #include "ntt.h"
+#include "rej_uniform.h"
 #include "symmetric.h"
 #include "randombytes.h"
 
@@ -100,43 +101,6 @@ static void unpack_ciphertext(polyvec *b, poly *v, const uint8_t c[KYBER_INDCPA_
     poly_decompress(v, c + KYBER_POLYVECCOMPRESSEDBYTES);
 }
 
-/*************************************************
-* Name:        rej_uniform
-*
-* Description: Run rejection sampling on uniform random bytes to generate
-*              uniform random integers mod q
-*
-* Arguments:   - int16_t *r: pointer to output buffer
-*              - unsigned int len: requested number of 16-bit integers (uniform mod q)
-*              - const uint8_t *buf: pointer to input buffer (assumed to be uniformly random bytes)
-*              - unsigned int buflen: length of input buffer in bytes
-*
-* Returns number of sampled 16-bit integers (at most len)
-**************************************************/
-static unsigned int rej_uniform(int16_t *r,
-                                unsigned int len,
-                                const uint8_t *buf,
-                                unsigned int buflen) {
-    unsigned int ctr, pos;
-    uint16_t val0, val1;
-
-    ctr = pos = 0;
-    while (ctr < len && pos + 3 <= buflen) {
-        val0 = ((buf[pos + 0] >> 0) | ((uint16_t)buf[pos + 1] << 8)) & 0xFFF;
-        val1 = ((buf[pos + 1] >> 4) | ((uint16_t)buf[pos + 2] << 4)) & 0xFFF;
-        pos += 3;
-
-        if (val0 < KYBER_Q) {
-            r[ctr++] = val0;
-        }
-        if (ctr < len && val1 < KYBER_Q) {
-            r[ctr++] = val1;
-        }
-    }
-
-    return ctr;
-}
-
 #define gen_a(A,B)  gen_matrix(A,B,0)
 #define gen_at(A,B) gen_matrix(A,B,1)
 
diff --git a/mlkem/rej_uniform.c b/mlkem/rej_uniform.c
new file mode 100644
index 000000000..7e1d212ca
--- /dev/null
+++ b/mlkem/rej_uniform.c
@@ -0,0 +1,369 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <arm_neon.h>
+#include <string.h>
+#include "rej_uniform_asm.h"
+#include "params.h"
+#include "rej_uniform.h"
+
+const uint8_t table_idx[256][16] = {
+    {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1}, // 0
+    {0, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 1
+    {2, 3, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 2
+    {0, 1, 2, 3, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 3
+    {4, 5, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 4
+    {0, 1, 4, 5, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 5
+    {2, 3, 4, 5, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 6
+    {0, 1, 2, 3, 4, 5, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       // 7
+    {6, 7, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 8
+    {0, 1, 6, 7, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 9
+    {2, 3, 6, 7, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 10
+    {0, 1, 2, 3, 6, 7, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       // 11
+    {4, 5, 6, 7, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 12
+    {0, 1, 4, 5, 6, 7, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       // 13
+    {2, 3, 4, 5, 6, 7, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       // 14
+    {0, 1, 2, 3, 4, 5, 6, 7, -1, -1, -1, -1, -1, -1, -1, -1},         // 15
+    {8, 9, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 16
+    {0, 1, 8, 9, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 17
+    {2, 3, 8, 9, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 18
+    {0, 1, 2, 3, 8, 9, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       // 19
+    {4, 5, 8, 9, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 20
+    {0, 1, 4, 5, 8, 9, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       // 21
+    {2, 3, 4, 5, 8, 9, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       // 22
+    {0, 1, 2, 3, 4, 5, 8, 9, -1, -1, -1, -1, -1, -1, -1, -1},         // 23
+    {6, 7, 8, 9, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 24
+    {0, 1, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       // 25
+    {2, 3, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       // 26
+    {0, 1, 2, 3, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, -1, -1},         // 27
+    {4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       // 28
+    {0, 1, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, -1, -1},         // 29
+    {2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, -1, -1},         // 30
+    {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1},           // 31
+    {10, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1}, // 32
+    {0, 1, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 33
+    {2, 3, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 34
+    {0, 1, 2, 3, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 35
+    {4, 5, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 36
+    {0, 1, 4, 5, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 37
+    {2, 3, 4, 5, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 38
+    {0, 1, 2, 3, 4, 5, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1},       // 39
+    {6, 7, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 40
+    {0, 1, 6, 7, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 41
+    {2, 3, 6, 7, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 42
+    {0, 1, 2, 3, 6, 7, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1},       // 43
+    {4, 5, 6, 7, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 44
+    {0, 1, 4, 5, 6, 7, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1},       // 45
+    {2, 3, 4, 5, 6, 7, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1},       // 46
+    {0, 1, 2, 3, 4, 5, 6, 7, 10, 11, -1, -1, -1, -1, -1, -1},         // 47
+    {8, 9, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 48
+    {0, 1, 8, 9, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 49
+    {2, 3, 8, 9, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 50
+    {0, 1, 2, 3, 8, 9, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1},       // 51
+    {4, 5, 8, 9, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 52
+    {0, 1, 4, 5, 8, 9, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1},       // 53
+    {2, 3, 4, 5, 8, 9, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1},       // 54
+    {0, 1, 2, 3, 4, 5, 8, 9, 10, 11, -1, -1, -1, -1, -1, -1},         // 55
+    {6, 7, 8, 9, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 56
+    {0, 1, 6, 7, 8, 9, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1},       // 57
+    {2, 3, 6, 7, 8, 9, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1},       // 58
+    {0, 1, 2, 3, 6, 7, 8, 9, 10, 11, -1, -1, -1, -1, -1, -1},         // 59
+    {4, 5, 6, 7, 8, 9, 10, 11, -1, -1, -1, -1, -1, -1, -1, -1},       // 60
+    {0, 1, 4, 5, 6, 7, 8, 9, 10, 11, -1, -1, -1, -1, -1, -1},         // 61
+    {2, 3, 4, 5, 6, 7, 8, 9, 10, 11, -1, -1, -1, -1, -1, -1},         // 62
+    {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, -1, -1, -1, -1},           // 63
+    {12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1}, // 64
+    {0, 1, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 65
+    {2, 3, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 66
+    {0, 1, 2, 3, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 67
+    {4, 5, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 68
+    {0, 1, 4, 5, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 69
+    {2, 3, 4, 5, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 70
+    {0, 1, 2, 3, 4, 5, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},       // 71
+    {6, 7, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 72
+    {0, 1, 6, 7, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 73
+    {2, 3, 6, 7, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 74
+    {0, 1, 2, 3, 6, 7, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},       // 75
+    {4, 5, 6, 7, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 76
+    {0, 1, 4, 5, 6, 7, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},       // 77
+    {2, 3, 4, 5, 6, 7, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},       // 78
+    {0, 1, 2, 3, 4, 5, 6, 7, 12, 13, -1, -1, -1, -1, -1, -1},         // 79
+    {8, 9, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 80
+    {0, 1, 8, 9, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 81
+    {2, 3, 8, 9, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 82
+    {0, 1, 2, 3, 8, 9, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},       // 83
+    {4, 5, 8, 9, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 84
+    {0, 1, 4, 5, 8, 9, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},       // 85
+    {2, 3, 4, 5, 8, 9, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},       // 86
+    {0, 1, 2, 3, 4, 5, 8, 9, 12, 13, -1, -1, -1, -1, -1, -1},         // 87
+    {6, 7, 8, 9, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 88
+    {0, 1, 6, 7, 8, 9, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},       // 89
+    {2, 3, 6, 7, 8, 9, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},       // 90
+    {0, 1, 2, 3, 6, 7, 8, 9, 12, 13, -1, -1, -1, -1, -1, -1},         // 91
+    {4, 5, 6, 7, 8, 9, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},       // 92
+    {0, 1, 4, 5, 6, 7, 8, 9, 12, 13, -1, -1, -1, -1, -1, -1},         // 93
+    {2, 3, 4, 5, 6, 7, 8, 9, 12, 13, -1, -1, -1, -1, -1, -1},         // 94
+    {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 13, -1, -1, -1, -1},           // 95
+    {10, 11, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1}, // 96
+    {0, 1, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 97
+    {2, 3, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 98
+    {0, 1, 2, 3, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},     // 99
+    {4, 5, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 100
+    {0, 1, 4, 5, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},     // 101
+    {2, 3, 4, 5, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},     // 102
+    {0, 1, 2, 3, 4, 5, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1},       // 103
+    {6, 7, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 104
+    {0, 1, 6, 7, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},     // 105
+    {2, 3, 6, 7, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},     // 106
+    {0, 1, 2, 3, 6, 7, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1},       // 107
+    {4, 5, 6, 7, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},     // 108
+    {0, 1, 4, 5, 6, 7, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1},       // 109
+    {2, 3, 4, 5, 6, 7, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1},       // 110
+    {0, 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, -1, -1, -1, -1},         // 111
+    {8, 9, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 112
+    {0, 1, 8, 9, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},     // 113
+    {2, 3, 8, 9, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},     // 114
+    {0, 1, 2, 3, 8, 9, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1},       // 115
+    {4, 5, 8, 9, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},     // 116
+    {0, 1, 4, 5, 8, 9, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1},       // 117
+    {2, 3, 4, 5, 8, 9, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1},       // 118
+    {0, 1, 2, 3, 4, 5, 8, 9, 10, 11, 12, 13, -1, -1, -1, -1},         // 119
+    {6, 7, 8, 9, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1, -1, -1},     // 120
+    {0, 1, 6, 7, 8, 9, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1},       // 121
+    {2, 3, 6, 7, 8, 9, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1},       // 122
+    {0, 1, 2, 3, 6, 7, 8, 9, 10, 11, 12, 13, -1, -1, -1, -1},         // 123
+    {4, 5, 6, 7, 8, 9, 10, 11, 12, 13, -1, -1, -1, -1, -1, -1},       // 124
+    {0, 1, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, -1, -1, -1, -1},         // 125
+    {2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, -1, -1, -1, -1},         // 126
+    {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, -1, -1},           // 127
+    {14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1}, // 128
+    {0, 1, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 129
+    {2, 3, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 130
+    {0, 1, 2, 3, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 131
+    {4, 5, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 132
+    {0, 1, 4, 5, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 133
+    {2, 3, 4, 5, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 134
+    {0, 1, 2, 3, 4, 5, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},       // 135
+    {6, 7, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 136
+    {0, 1, 6, 7, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 137
+    {2, 3, 6, 7, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 138
+    {0, 1, 2, 3, 6, 7, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},       // 139
+    {4, 5, 6, 7, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 140
+    {0, 1, 4, 5, 6, 7, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},       // 141
+    {2, 3, 4, 5, 6, 7, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},       // 142
+    {0, 1, 2, 3, 4, 5, 6, 7, 14, 15, -1, -1, -1, -1, -1, -1},         // 143
+    {8, 9, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 144
+    {0, 1, 8, 9, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 145
+    {2, 3, 8, 9, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 146
+    {0, 1, 2, 3, 8, 9, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},       // 147
+    {4, 5, 8, 9, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 148
+    {0, 1, 4, 5, 8, 9, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},       // 149
+    {2, 3, 4, 5, 8, 9, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},       // 150
+    {0, 1, 2, 3, 4, 5, 8, 9, 14, 15, -1, -1, -1, -1, -1, -1},         // 151
+    {6, 7, 8, 9, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},     // 152
+    {0, 1, 6, 7, 8, 9, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},       // 153
+    {2, 3, 6, 7, 8, 9, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},       // 154
+    {0, 1, 2, 3, 6, 7, 8, 9, 14, 15, -1, -1, -1, -1, -1, -1},         // 155
+    {4, 5, 6, 7, 8, 9, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},       // 156
+    {0, 1, 4, 5, 6, 7, 8, 9, 14, 15, -1, -1, -1, -1, -1, -1},         // 157
+    {2, 3, 4, 5, 6, 7, 8, 9, 14, 15, -1, -1, -1, -1, -1, -1},         // 158
+    {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 14, 15, -1, -1, -1, -1},           // 159
+    {10, 11, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1}, // 160
+    {0, 1, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 161
+    {2, 3, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 162
+    {0, 1, 2, 3, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 163
+    {4, 5, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 164
+    {0, 1, 4, 5, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 165
+    {2, 3, 4, 5, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 166
+    {0, 1, 2, 3, 4, 5, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1},       // 167
+    {6, 7, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 168
+    {0, 1, 6, 7, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 169
+    {2, 3, 6, 7, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 170
+    {0, 1, 2, 3, 6, 7, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1},       // 171
+    {4, 5, 6, 7, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 172
+    {0, 1, 4, 5, 6, 7, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1},       // 173
+    {2, 3, 4, 5, 6, 7, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1},       // 174
+    {0, 1, 2, 3, 4, 5, 6, 7, 10, 11, 14, 15, -1, -1, -1, -1},         // 175
+    {8, 9, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 176
+    {0, 1, 8, 9, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 177
+    {2, 3, 8, 9, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 178
+    {0, 1, 2, 3, 8, 9, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1},       // 179
+    {4, 5, 8, 9, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 180
+    {0, 1, 4, 5, 8, 9, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1},       // 181
+    {2, 3, 4, 5, 8, 9, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1},       // 182
+    {0, 1, 2, 3, 4, 5, 8, 9, 10, 11, 14, 15, -1, -1, -1, -1},         // 183
+    {6, 7, 8, 9, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 184
+    {0, 1, 6, 7, 8, 9, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1},       // 185
+    {2, 3, 6, 7, 8, 9, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1},       // 186
+    {0, 1, 2, 3, 6, 7, 8, 9, 10, 11, 14, 15, -1, -1, -1, -1},         // 187
+    {4, 5, 6, 7, 8, 9, 10, 11, 14, 15, -1, -1, -1, -1, -1, -1},       // 188
+    {0, 1, 4, 5, 6, 7, 8, 9, 10, 11, 14, 15, -1, -1, -1, -1},         // 189
+    {2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 14, 15, -1, -1, -1, -1},         // 190
+    {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 14, 15, -1, -1},           // 191
+    {12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1}, // 192
+    {0, 1, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 193
+    {2, 3, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 194
+    {0, 1, 2, 3, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 195
+    {4, 5, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 196
+    {0, 1, 4, 5, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 197
+    {2, 3, 4, 5, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 198
+    {0, 1, 2, 3, 4, 5, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},       // 199
+    {6, 7, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 200
+    {0, 1, 6, 7, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 201
+    {2, 3, 6, 7, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 202
+    {0, 1, 2, 3, 6, 7, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},       // 203
+    {4, 5, 6, 7, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 204
+    {0, 1, 4, 5, 6, 7, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},       // 205
+    {2, 3, 4, 5, 6, 7, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},       // 206
+    {0, 1, 2, 3, 4, 5, 6, 7, 12, 13, 14, 15, -1, -1, -1, -1},         // 207
+    {8, 9, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},   // 208
+    {0, 1, 8, 9, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 209
+    {2, 3, 8, 9, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 210
+    {0, 1, 2, 3, 8, 9, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},       // 211
+    {4, 5, 8, 9, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 212
+    {0, 1, 4, 5, 8, 9, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},       // 213
+    {2, 3, 4, 5, 8, 9, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},       // 214
+    {0, 1, 2, 3, 4, 5, 8, 9, 12, 13, 14, 15, -1, -1, -1, -1},         // 215
+    {6, 7, 8, 9, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},     // 216
+    {0, 1, 6, 7, 8, 9, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},       // 217
+    {2, 3, 6, 7, 8, 9, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},       // 218
+    {0, 1, 2, 3, 6, 7, 8, 9, 12, 13, 14, 15, -1, -1, -1, -1},         // 219
+    {4, 5, 6, 7, 8, 9, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},       // 220
+    {0, 1, 4, 5, 6, 7, 8, 9, 12, 13, 14, 15, -1, -1, -1, -1},         // 221
+    {2, 3, 4, 5, 6, 7, 8, 9, 12, 13, 14, 15, -1, -1, -1, -1},         // 222
+    {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 13, 14, 15, -1, -1},           // 223
+    {10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1}, // 224
+    {0, 1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},   // 225
+    {2, 3, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},   // 226
+    {0, 1, 2, 3, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},     // 227
+    {4, 5, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},   // 228
+    {0, 1, 4, 5, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},     // 229
+    {2, 3, 4, 5, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},     // 230
+    {0, 1, 2, 3, 4, 5, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1},       // 231
+    {6, 7, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},   // 232
+    {0, 1, 6, 7, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},     // 233
+    {2, 3, 6, 7, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},     // 234
+    {0, 1, 2, 3, 6, 7, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1},       // 235
+    {4, 5, 6, 7, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},     // 236
+    {0, 1, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1},       // 237
+    {2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1},       // 238
+    {0, 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, -1, -1},         // 239
+    {8, 9, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1},   // 240
+    {0, 1, 8, 9, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},     // 241
+    {2, 3, 8, 9, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},     // 242
+    {0, 1, 2, 3, 8, 9, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1},       // 243
+    {4, 5, 8, 9, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},     // 244
+    {0, 1, 4, 5, 8, 9, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1},       // 245
+    {2, 3, 4, 5, 8, 9, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1},       // 246
+    {0, 1, 2, 3, 4, 5, 8, 9, 10, 11, 12, 13, 14, 15, -1, -1},         // 247
+    {6, 7, 8, 9, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1},     // 248
+    {0, 1, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1},       // 249
+    {2, 3, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1},       // 250
+    {0, 1, 2, 3, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, -1, -1},         // 251
+    {4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1},       // 252
+    {0, 1, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, -1, -1},         // 253
+    {2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, -1, -1},         // 254
+    {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15},           // 255
+};
+
+const uint16_t bit_table[8] = {0x1, 0x2, 0x4, 0x8, 0x10, 0x20, 0x40, 0x80};
+/*************************************************
+* Name:        rej_uniform_large
+*
+* Description: Rejection sampling on uniform random bytes to generate
+*              uniform random integers mod q
+*
+* Arguments:   - int16_t *r:          pointer to output buffer
+*              - unsigned int len:    requested number of 16-bit integers
+*                                     (uniform mod q)
+*              - const uint8_t *buf:  pointer to input buffer
+*                                     (assumed to be uniform random bytes)
+*              - unsigned int buflen: length of input buffer in bytes
+*              - unsigned int *consumed: the length of consumed buffer
+* Returns number of sampled 16-bit integers (at most len)
+**************************************************/
+static unsigned int rej_uniform_large(int16_t *r, unsigned int len,
+                                     const uint8_t *buf, unsigned int buflen,
+                                     unsigned int *consumed) {
+
+    // Ensure alignment, the minimum stack size is (len + 32) * sizeof(int16_t)
+    // Since we don't want to use malloc/free, we assume the maximum len = KYBER_N and use stack.
+    int16_t stack[KYBER_N + 32] = {0};
+    unsigned int count;
+
+    count = rej_uniform_asm(stack, buf, consumed, buflen, len, table_idx, bit_table);
+
+    unsigned int min = (count < len ? count : len);
+    memcpy(r, stack, min * sizeof(uint16_t));
+
+    return min;
+
+}
+
+/*************************************************
+* Name:        rej_uniform_scalar
+*
+* Description: Run rejection sampling on uniform random bytes to generate
+*              uniform random integers mod q
+*
+* Arguments:   - int16_t *r:          pointer to output buffer
+*              - unsigned int len:    requested number of 16-bit integers
+*                                     (uniform mod q)
+*              - const uint8_t *buf:  pointer to input buffer
+*                                     (assumed to be uniform random bytes)
+*              - unsigned int buflen: length of input buffer in bytes
+*
+* Returns number of sampled 16-bit integers (at most len)
+**************************************************/
+static unsigned int rej_uniform_scalar(int16_t *r,
+                                       unsigned int len,
+                                       const uint8_t *buf,
+                                       unsigned int buflen) {
+    unsigned int ctr, pos;
+    uint16_t val0, val1;
+
+    ctr = pos = 0;
+    while (ctr < len && pos + 3 <= buflen) {
+        val0 = ((buf[pos + 0] >> 0) | ((uint16_t)buf[pos + 1] << 8)) & 0xFFF;
+        val1 = ((buf[pos + 1] >> 4) | ((uint16_t)buf[pos + 2] << 4)) & 0xFFF;
+        pos += 3;
+
+        if (val0 < KYBER_Q) {
+            r[ctr++] = val0;
+        }
+        if (ctr < len && val1 < KYBER_Q) {
+            r[ctr++] = val1;
+        }
+    }
+    return ctr;
+}
+
+/*************************************************
+* Name:        rej_uniform
+*
+* Description: Run rejection sampling on uniform random bytes to generate
+*              uniform random integers mod q
+*
+* Arguments:   - int16_t *r:          pointer to output buffer
+*              - unsigned int len:    requested number of 16-bit integers
+*                                     (uniform mod q)
+*              - const uint8_t *buf:  pointer to input buffer
+*                                     (assumed to be uniform random bytes)
+*              - unsigned int buflen: length of input buffer in bytes
+*
+* Returns number of sampled 16-bit integers (at most len)
+**************************************************/
+unsigned int rej_uniform(int16_t *r,
+                         unsigned int len,
+                         const uint8_t *buf,
+                         unsigned int buflen) {
+
+    unsigned int ctr, consumed = 0;
+
+    // Sample from large buffer with full lane as much as possible.
+    ctr = rej_uniform_large(r, len, buf, buflen, &consumed);
+    if (ctr < len) {
+        // This function will utilize every last byte of the buffer.
+        ctr += rej_uniform_scalar(r + ctr, len - ctr, buf + consumed, buflen - consumed);
+    }
+
+    return ctr;
+}
diff --git a/mlkem/rej_uniform.h b/mlkem/rej_uniform.h
new file mode 100644
index 000000000..9a5d2bf7d
--- /dev/null
+++ b/mlkem/rej_uniform.h
@@ -0,0 +1,11 @@
+// SPDX-License-Identifier: Apache-2.0
+#ifndef REJ_UNIFORM_H
+#define REJ_UNIFORM_H
+
+#define rej_uniform KYBER_NAMESPACE(rej_uniform)
+unsigned int rej_uniform(int16_t *r,
+                         unsigned int len,
+                         const uint8_t *buf,
+                         unsigned int buflen);
+
+#endif
diff --git a/mlkem/rej_uniform_asm.h b/mlkem/rej_uniform_asm.h
new file mode 100644
index 000000000..943890162
--- /dev/null
+++ b/mlkem/rej_uniform_asm.h
@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: Apache-2.0
+#ifndef REJ_UNIFORM_ASM
+#define REJ_UNIFORM_ASM
+
+unsigned int rej_uniform_asm(int16_t *local_buf,
+                             const uint8_t *buf,
+                             unsigned int *buf_consumed,
+                             unsigned int buflen,
+                             unsigned int len,
+                             const uint8_t idx[256][16],
+                             const uint16_t bits[8]);
+
+#endif
diff --git a/mlkem/rej_uniform_asm.s b/mlkem/rej_uniform_asm.s
new file mode 100644
index 000000000..8fff58936
--- /dev/null
+++ b/mlkem/rej_uniform_asm.s
@@ -0,0 +1,268 @@
+// SPDX-License-Identifier: Apache-2.0
+#include "params.h"
+
+.text:
+
+.macro div48    dst, src
+    mov     w8, #43691
+    movk    w8, #43690, lsl #16
+    umull   x8, \src, w8
+    lsr     x8, x8, #37
+    add     w8, w8, w8, lsl #1
+    lsl     \dst, w8, #4
+.endm
+/*************************************************
+* Name:        rej_uniform_asm
+*
+* Description: Full SIMD lane, run rejection sampling on uniform random bytes to generate
+*              uniform random integers mod q
+*
+* Arguments:   - int16_t *r:          pointer to output buffer
+*              - unsigned int len:    requested number of 16-bit integers
+*                                     (uniform mod q)
+*              - const uint8_t *buf:  pointer to input buffer
+*                                     (assumed to be uniform random bytes)
+*              - unsigned int buflen: length of input buffer in bytes
+*              - unsigned int *consumed: the length of consumed buffer
+* Returns number of sampled 16-bit integers (at most len)
+**************************************************/
+.align 4
+.global     rej_uniform_asm
+.global     _rej_uniform_asm
+rej_uniform_asm:
+_rej_uniform_asm:
+
+    /* Input registers */
+    stack                       .req x0
+    counter                     .req w0
+    buf                         .req x1
+    buf_consumed                .req x2
+    buflen                      .req w3
+    len                         .req x4
+    lenw                        .req w4
+    table_idx                   .req x5
+    bit_table                   .req x6
+
+    /* Output registers */
+    output                      .req x11
+
+    /* Temporary registers */
+    tmp                         .req w8
+    count                       .req w8
+    bound                       .req w9
+    iterw                       .req w10
+    iter                        .req x10
+
+    rec_idx_0                   .req w12
+    rec_idx_1                   .req w13
+    rec_idx_2                   .req w14
+    rec_idx_3                   .req w15
+
+    ctr0                        .req w12
+    ctr1                        .req w13
+    ctr2                        .req w14
+    ctr3                        .req w15
+
+    /* Vector registers */
+
+    buf0                        .req v0
+    buf1                        .req v1
+    buf2                        .req v2
+
+    tmp0                        .req v4
+    tmp1                        .req v5
+    tmp2                        .req v6
+    tmp3                        .req v7
+
+    sign0                       .req v4
+    sign1                       .req v5
+    sign2                       .req v6
+    sign3                       .req v7
+
+    val0                        .req v16
+    val0q                       .req q16
+    val1                        .req v17
+    val1q                       .req q17
+    val2                        .req v18
+    val2q                       .req q18
+    val3                        .req v19
+    val3q                       .req q19
+
+    t0                          .req s20
+    t1                          .req s21
+    t2                          .req s22
+    t3                          .req s23
+
+    table0                      .req v24
+    table0q                     .req q24
+    table1                      .req v25
+    table1q                     .req q25
+    table2                      .req v26
+    table2q                     .req q26
+    table3                      .req v27
+    table3q                     .req q27
+
+    kyber_q                     .req v30
+    bits                        .req v31
+    bits_q                      .req q31
+
+
+    /* Vectorize code start */
+
+    ldr bits_q, [bit_table]
+    movz tmp, #KYBER_Q
+    dup.8h kyber_q, tmp
+    div48   bound, buflen
+
+    mov     iterw, #0
+    mov output, stack
+
+    loop48:
+        add     x8, buf, iter
+
+        ld3.16b {buf0, buf1, buf2}, [x8]
+        add iterw, iterw, #48
+
+        zip1.16b tmp0, buf0, buf1
+        zip2.16b tmp1, buf0, buf1
+        zip1.16b tmp2, buf1, buf2
+        zip2.16b tmp3, buf1, buf2
+
+        bic.8h tmp0, #0xf0, lsl 8
+        bic.8h tmp1, #0xf0, lsl 8
+        ushr.8h tmp2, tmp2, #4
+        ushr.8h tmp3, tmp3, #4
+
+        zip1.8h val0, tmp0, tmp2
+        zip2.8h val1, tmp0, tmp2
+        zip1.8h val2, tmp1, tmp3
+        zip2.8h val3, tmp1, tmp3
+
+        cmhi.8h sign0, kyber_q, val0
+        cmhi.8h sign1, kyber_q, val1
+        cmhi.8h sign2, kyber_q, val2
+        cmhi.8h sign3, kyber_q, val3
+
+        and.16b sign0, sign0, bits
+        and.16b sign1, sign1, bits
+        and.16b sign2, sign2, bits
+        and.16b sign3, sign3, bits
+
+        uaddlv.8h t0, sign0
+        uaddlv.8h t1, sign1
+        uaddlv.8h t2, sign2
+        uaddlv.8h t3, sign3
+
+        fmov rec_idx_0, t0
+        fmov rec_idx_1, t1
+        fmov rec_idx_2, t2
+        fmov rec_idx_3, t3
+
+        ldr table0q, [table_idx, rec_idx_0, uxtw #4]
+        ldr table1q, [table_idx, rec_idx_1, uxtw #4]
+        ldr table2q, [table_idx, rec_idx_2, uxtw #4]
+        ldr table3q, [table_idx, rec_idx_3, uxtw #4]
+
+        cnt.16b sign0, sign0
+        cnt.16b sign1, sign1
+        cnt.16b sign2, sign2
+        cnt.16b sign3, sign3
+
+        uaddlv.8h t0, sign0
+        uaddlv.8h t1, sign1
+        uaddlv.8h t2, sign2
+        uaddlv.8h t3, sign3
+
+        fmov ctr0, t0
+        fmov ctr1, t1
+        fmov ctr2, t2
+        fmov ctr3, t3
+
+        tbl.16b val0, {val0}, table0
+        tbl.16b val1, {val1}, table1
+        tbl.16b val2, {val2}, table2
+        tbl.16b val3, {val3}, table3
+
+        str val0q, [output]
+        add output, output, ctr0, uxtw #1
+
+        str val1q, [output]
+        add output, output, ctr1, uxtw #1
+
+        str val2q, [output]
+        add output, output, ctr2, uxtw #1
+
+        str val3q, [output]
+        add output, output, ctr3, uxtw #1
+
+        sub     x8, output, stack
+        lsr     x8, x8, #1
+
+        cmp count, lenw
+        b.hs    end
+
+        cmp iterw, bound
+        b.lo    loop48
+
+    loop24:
+
+        add x8, buf, iter
+
+        ld3.8b {buf0, buf1, buf2}, [x8]
+        add iterw, iterw, #24
+
+        zip1.16b tmp0, buf0, buf1
+        zip1.16b tmp1, buf1, buf2
+
+        bic.8h tmp0, #0xf0, lsl 8
+        ushr.8h tmp1, tmp1, #4
+
+        zip1.8h val0, tmp0, tmp1
+        zip2.8h val1, tmp0, tmp1
+
+        cmhi.8h sign0, kyber_q, val0
+        cmhi.8h sign1, kyber_q, val1
+
+        and.16b sign0, sign0, bits
+        and.16b sign1, sign1, bits
+
+        uaddlv.8h t0, sign0
+        uaddlv.8h t1, sign1
+
+        fmov rec_idx_0, t0
+        fmov rec_idx_1, t1
+
+        ldr table0q, [table_idx, rec_idx_0, uxtw #4]
+        ldr table1q, [table_idx, rec_idx_1, uxtw #4]
+
+        cnt.16b sign0, sign0
+        cnt.16b sign1, sign1
+
+        uaddlv.8h t0, sign0
+        uaddlv.8h t1, sign1
+
+        fmov ctr0, t0
+        fmov ctr1, t1
+
+        tbl.16b val0, {val0}, table0
+        tbl.16b val1, {val1}, table1
+
+        str val0q, [output]
+        add output, output, ctr0, uxtw #1
+
+        str val1q, [output]
+        add output, output, ctr1, uxtw #1
+
+        sub x8, output, stack
+        lsr x8, x8, #1
+
+        cmp count, lenw
+        b.hs    end
+
+        cmp iterw, buflen
+        b.lo    loop24
+
+    end:
+        mov counter, count
+        str iterw, [buf_consumed]
+        ret
diff --git a/scripts/checksum b/scripts/checksum
index 4066d6158..e66af9685 100755
--- a/scripts/checksum
+++ b/scripts/checksum
@@ -3,7 +3,12 @@
 
 # This script executes a binary file, captures its output, then generates and compares its SHA-256 hash with a provided one.
 
-output_hash=$(./$1 | sha256sum | awk '{ print $1 }')
+if [[ "$OSTYPE" == "darwin"* ]]; then
+    output_hash=$(./$1 | sha2 -256 | awk '{ print $4 }')
+else
+    output_hash=$(./$1 | sha256sum | awk '{ print $1 }')
+fi
+
 
 if [[ ${output_hash} == "${2}" ]]; then
   echo "${1#*_} Hashes match."