diff --git a/code/math/abs.c b/code/math/abs.c
new file mode 100644
index 0000000..246376b
--- /dev/null
+++ b/code/math/abs.c
@@ -0,0 +1,16 @@
+
+#include <math.h>
+
+double fabs(double x) {
+    if(x >= 0) {
+        return x;
+    }
+    return -x;
+}
+
+float fabsf(float x) {
+    if(x >= 0) {
+        return x;
+    }
+    return -x;
+}
diff --git a/code/math/acos.c b/code/math/acos.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/acosh.c b/code/math/acosh.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/asin.c b/code/math/asin.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/asinh.c b/code/math/asinh.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/atan.c b/code/math/atan.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/atanh.c b/code/math/atanh.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/cbrt.c b/code/math/cbrt.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/ceil.c b/code/math/ceil.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/copysign.c b/code/math/copysign.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/cosh.c b/code/math/cosh.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/erf.c b/code/math/erf.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/erfc.c b/code/math/erfc.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/exp.c b/code/math/exp.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/fdim.c b/code/math/fdim.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/floats.c b/code/math/floats.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/floor.c b/code/math/floor.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/fma.c b/code/math/fma.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/fmax.c b/code/math/fmax.c
new file mode 100644
index 0000000..ca5193a
--- /dev/null
+++ b/code/math/fmax.c
@@ -0,0 +1,12 @@
+
+double fmax(double x, double y) {
+    if(x>y) return x;
+    return y;
+}
+
+float fmaxf(float x, float y) {
+    if(x>y) return x;
+    return y;
+}
+
+
diff --git a/code/math/fmod.c b/code/math/fmod.c
new file mode 100644
index 0000000..2029d25
--- /dev/null
+++ b/code/math/fmod.c
@@ -0,0 +1,18 @@
+
+double fmod(double x, double y) {
+    int n = 0;
+    while(y < x*n) {
+        ++n;
+    }
+    return y - n*x;
+}
+
+float fmodf(float x, float y) {
+    int n = 0;
+    while(y < x*n) {
+        ++n;
+    }
+    return y - n*x;
+}
+
+
diff --git a/code/math/frexp.c b/code/math/frexp.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/hypot.c b/code/math/hypot.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/ilogb.c b/code/math/ilogb.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/ldexp.c b/code/math/ldexp.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/lgamma.c b/code/math/lgamma.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/llrint.c b/code/math/llrint.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/llround.c b/code/math/llround.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/log.c b/code/math/log.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/lrint.c b/code/math/lrint.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/mod.c b/code/math/mod.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/nan.c b/code/math/nan.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/nearbyint.c b/code/math/nearbyint.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/nextafter.c b/code/math/nextafter.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/pow.c b/code/math/pow.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/remainder.c b/code/math/remainder.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/remquo.c b/code/math/remquo.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/rint.c b/code/math/rint.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/scalbln.c b/code/math/scalbln.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/scalbnf.c b/code/math/scalbnf.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/sin.c b/code/math/sin.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/sinh.c b/code/math/sinh.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/sqrt.c b/code/math/sqrt.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/tan.c b/code/math/tan.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/tanh.c b/code/math/tanh.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/tgamma.c b/code/math/tgamma.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/math/trunc.c b/code/math/trunc.c
new file mode 100644
index 0000000..e69de29
diff --git a/code/os/win/win.h b/code/os/win/win.h
index 8a0186c..e0abec8 100644
--- a/code/os/win/win.h
+++ b/code/os/win/win.h
@@ -1,6 +1,8 @@
 
 #pragma once
 
+#include <_os.h>
+
 #define WIN32_LEAN_AND_MEAN
 #include <Windows.h>
 
diff --git a/code/os/win/win_io.c b/code/os/win/win_io.c
index f7bb2af..49d0834 100644
--- a/code/os/win/win_io.c
+++ b/code/os/win/win_io.c
@@ -1,11 +1,84 @@
 
 #include "win.h"
 
+#include <stddef.h>
+#include <stdio.h>
+
 // It's just mapped directly to HANDLE
 struct FILE {
     int unused;
 };
 
+int _os_del_file(char const *filename) {
+    int ok = DeleteFileA(filename);
+    return ok != 0;
+}
+
+int _os_mov_file(char const *old, char const *new) {
+    int ok = MoveFileA(old, new);
+    return ok != 0;
+}
+
+char *_os_tmpname(char *buffer) {
+    static UINT uniq = 0;
+    DWORD path_len = GetTempPathA(L_tmpnam, buffer);
+    if(path_len == 0) return NULL;
+    UINT ok = GetTempFileNameA(buffer, "", uniq, buffer);
+    if(ok == 0) return NULL;
+    return buffer;
+}
+
+FILE *_os_fopen(char const *restrict name, _OS_ModeFlags flags) {
+    DWORD desaddr = 0;
+    DWORD share = 0;
+    DWORD disp = 0;
+    switch(flags.base_mode) {
+        case 'r': {
+            desaddr = GENERIC_READ;
+            if(!flags.update) {
+                share = FILE_SHARE_READ;
+            }
+            disp = OPEN_EXISTING;
+            if(flags.update) {
+                disp = OPEN_ALWAYS;
+            }
+        } break;
+        case 'w': {
+            desaddr = GENERIC_WRITE;
+            disp = CREATE_ALWAYS;
+        } break;
+        case 'a': {
+            desaddr = GENERIC_WRITE;
+
+        } break;
+    }
+    if(flags.exclusive) {
+        disp = CREATE_NEW;
+    }
+
+    HANDLE fileHandle = CreateFileA(
+        name,
+        desaddr,
+        share,
+        NULL,
+        disp,
+        FILE_ATTRIBUTE_NORMAL,
+        NULL
+    );
+    FILE *file = (FILE *)fileHandle;
+    if(fileHandle == INVALID_HANDLE_VALUE) {
+        file = NULL;
+    }
+
+    return file;
+}
+
+int _os_fclose(FILE *file) {
+    HANDLE fileHandle = (HANDLE)file;
+    BOOL ok = CloseHandle(fileHandle);
+    return ok != 0;
+}
+
 void _os_file_write(void* ctx, size_t n, const char str[]) {
     DWORD written = 0;
     WriteFile((HANDLE) ctx, str, n, &written, NULL);
diff --git a/code/stdio.c b/code/stdio.c
index 21f69a4..d97e1e7 100644
--- a/code/stdio.c
+++ b/code/stdio.c
@@ -1,13 +1,71 @@
 #include <stdio.h>
 #include <stdarg.h>
 #include <ctype.h>
+#include <stdbool.h>
 
 #include <_os.h>
 
 #define __STDC_WANT_LIB_EXT1__ 1
 #include <string.h>
 
-#include <_os.h>
+int remove(const char *filename)
+{
+    return _os_del_file(filename);
+}
+
+int rename(const char *old, const char *new)
+{
+    return _os_mov_file(old, new);
+}
+
+char *tmpnam(char *s)
+{
+    static char static_buffer[L_tmpnam];
+    char *buffer = s;
+    if(s == NULL) buffer = static_buffer;
+    return _os_tmpname(buffer);
+}
+
+FILE *fopen(const char *restrict filename, const char *restrict mode)
+{
+    // Basically defined UB here by introducing missing modes
+    // It is simpler to implement that way I think.
+    int base_mode = mode[0];
+    int binary = 0;
+    int exclusive = 0;
+    int update = 0;
+    for(; *mode != 0; ++mode) {
+        if(*mode == 'x') exclusive = 1;
+        if(*mode == 'b') binary    = 1;
+        if(*mode == '+') update    = 1;
+    }
+    if(base_mode == 'r' && exclusive) return NULL;
+    if(base_mode == 'a' && exclusive) return NULL;
+    
+    _OS_ModeFlags mode_flags = {
+        .base_mode = base_mode,
+        .binary    = binary,
+        .update    = update,
+        .exclusive = exclusive,
+    };
+
+    return _os_fopen(filename, mode_flags);
+}
+
+int fclose(FILE *stream)
+{
+    return _os_fclose(stream);
+}
+
+// TODO:kekw:
+FILE *freopen(
+    const char *restrict filename,
+    const char *restrict mode,
+    FILE *restrict stream)
+{
+    fclose(stream);
+    return NULL;
+}
 
 typedef void(*OutputFunc)(void* ctx, size_t n, const char str[]);
 
@@ -28,10 +86,10 @@ typedef struct {
 FILE *stdout, *stderr, *stdin;
 
 #define CALL_PRINTF(fmt_func, ctx, out, fmt)       \
-va_list args;                                  \
-va_start(args, fmt);                           \
-int result = fmt_func(ctx, out, fmt, args);    \
-va_end(args)
+    va_list args;                                  \
+    va_start(args, fmt);                           \
+    int result = fmt_func(ctx, out, fmt, args);    \
+    va_end(args)
 
 static void string_write(void *ctx, size_t n, const char *restrict str) {
     StrPrintCtx *c = ctx;
diff --git a/inc/_os.h b/inc/_os.h
index 8a1860b..e3caa33 100644
--- a/inc/_os.h
+++ b/inc/_os.h
@@ -15,7 +15,24 @@
 #endif
 
 // OS-dependent IO Functions
-void _os_file_write(void* ctx, size_t n, const char str[]);
-_Noreturn void _os_exit(int code);
-void _os_init_eh();
+
+// TODO: see if we need this or will it be easier for linux to just pass
+// the mode string.
+typedef struct _OS_ModeFlags {
+    int base_mode;
+    int binary;
+    int update;
+    int exclusive;
+} _OS_ModeFlags;
+
 typedef struct FILE FILE;
+int   _os_del_file(char const *filename);
+int   _os_mov_file(char const *old, char const *new);
+char *_os_tmpname(char *buffer);
+FILE *_os_fopen(char const *restrict name, _OS_ModeFlags flags);
+int   _os_fclose(FILE *file);
+void  _os_file_write(void* ctx, size_t n, const char str[]);
+
+void _os_init_eh();
+
+_Noreturn void _os_exit(int code);
diff --git a/inc/math.h b/inc/math.h
index 22ece91..244aee2 100644
--- a/inc/math.h
+++ b/inc/math.h
@@ -11,221 +11,192 @@ typedef double double_t;
 #define INFINITY   ((float)(_HUGE_ENUF * _HUGE_ENUF))
 #define HUGE_VAL   ((double)INFINITY)
 #define HUGE_VALF  ((float)INFINITY)
-#define HUGE_VALL  ((long double)INFINITY)
 
-// Positive NaN
 #define NAN        (-(float)(INFINITY * 0.0F))
 
-#define FP_SUBNORMAL (-2)
-#define FP_NORMAL    (-1)
-#define FP_ZERO      0
-#define FP_INFINITE  1
-#define FP_NAN       2
+// FP_ILOGB0
+// FP_ILOGBNAN
 
-//FP_INFINITE
-//FP_NAN
-//FP_NORMAL
-//FP_SUBNORMAL
-//FP_ZERO
-#define FP_FAST_FMA  1
-#define FP_FAST_FMAF 1
-#define FP_FAST_FMAL 1
+#define MATH_ERRNO     0
+#define MATH_ERREXCEPT 1
 
-#define FP_ILOGB0   (-0x7FFFFFFFu - 1u)
-#define FP_ILOGBNAN 0x7FFFFFFFu
+#define math_errhandling MATH_ERRNO
 
-#define MATH_ERRNO        1
-#define MATH_ERREXCEPT    2
-#define math_errhandling  (MATH_ERRNO | MATH_ERREXCEPT)
-
-// TODO: implement this
-#define fpclassify(x) 0
-
-// HACK: If its fine just remove the comment
-#define isfinite(x)   ((double)(x) != HUGE_VAL && (double)(x) != -HUGE_VAL)
-#define isinf(x)      (!(isinf(x)))
-
-#define isnan(x)      0
-#define isnormal(x)   0
-#define signbit(x)    0
-
-// TODO: implement this, search it up, they're a bit different semantics than 
-// the names might suggest
-#define isgreater(x, y)      0
-#define isgreaterequal(x, y) 0
-#define isless(x, y)         0
-#define islessequal(x, y)    0
-#define islessgreater(x, y)  0
-#define isunordered(x, y)    0
+#define FP_INFINITE  0
+#define FP_NAN       1
+#define FP_NORMAL    2
+#define FP_SUBNORMAL 3
+#define FP_ZERO      4
+#define fpclassify(x) ( \
+    _is_float(x)  ? _fpclassify_f(x) :
+    _is_double(x) ? _fpclassify_d(x) :
+    FP_NAN)
 
 double acos(double x);
 float acosf(float x);
-long double acosl(long double x);
+
 double asin(double x);
 float asinf(float x);
-long double asinl(long double x);
+
 double atan(double x);
 float atanf(float x);
-long double atanl(long double x);
+
 double atan2(double y, double x);
 float atan2f(float y, float x);
-long double atan2l(long double y, long double x);
+
 double cos(double x);
 float cosf(float x);
-long double cosl(long double x);
+
 double sin(double x);
 float sinf(float x);
-long double sinl(long double x);
+
 double tan(double x);
 float tanf(float x);
-long double tanl(long double x);
+
 double acosh(double x);
 float acoshf(float x);
-long double acoshl(long double x);
+
 double asinh(double x);
 float asinhf(float x);
-long double asinhl(long double x);
+
 double atanh(double x);
 float atanhf(float x);
-long double atanhl(long double x);
+
 double cosh(double x);
 float coshf(float x);
-long double coshl(long double x);
+
 double sinh(double x);
 float sinhf(float x);
-long double sinhl(long double x);
+
 double tanh(double x);
 float tanhf(float x);
-long double tanhl(long double x);
+
 double exp(double x);
 float expf(float x);
-long double expl(long double x);
+
 double exp2(double x);
 float exp2f(float x);
-long double exp2l(long double x);
+
 double expm1(double x);
 float expm1f(float x);
-long double expm1l(long double x);
+
 double frexp(double value, int *exp);
 float frexpf(float value, int *exp);
-long double frexpl(long double value, int *exp);
+
 int ilogb(double x);
 int ilogbf(float x);
-int ilogbl(long double x);
+
 double ldexp(double x, int exp);
 float ldexpf(float x, int exp);
-long double ldexpl(long double x, int exp);
+
 double log(double x);
 float logf(float x);
-long double logl(long double x);
+
 double log10(double x);
 float log10f(float x);
-long double log10l(long double x);
+
 double log1p(double x);
 float log1pf(float x);
-long double log1pl(long double x);
+
 double log2(double x);
 float log2f(float x);
-long double log2l(long double x);
+
 double logb(double x);
 float logbf(float x);
-long double logbl(long double x);
+
 double modf(double value, double *iptr);
 float modff(float value, float *iptr);
-long double modfl(long double value, long double *iptr);
+
 double scalbn(double x, int n);
 float scalbnf(float x, int n);
-long double scalbnl(long double x, int n);
+
 double scalbln(double x, long int n);
 float scalblnf(float x, long int n);
-long double scalblnl(long double x, long int n);
+
 double cbrt(double x);
 float cbrtf(float x);
-long double cbrtl(long double x);
+
 double fabs(double x);
 float fabsf(float x);
-long double fabsl(long double x);
+
 double hypot(double x, double y);
 float hypotf(float x, float y);
-long double hypotl(long double x, long double y);
+
 double pow(double x, double y);
 float powf(float x, float y);
-long double powl(long double x, long double y);
+
 double sqrt(double x);
 float sqrtf(float x);
-long double sqrtl(long double x);
+
 double erf(double x);
 float erff(float x);
-long double erfl(long double x);
+
 double erfc(double x);
 float erfcf(float x);
-long double erfcl(long double x);
+
 double lgamma(double x);
 float lgammaf(float x);
-long double lgammal(long double x);
+
 double tgamma(double x);
 float tgammaf(float x);
-long double tgammal(long double x);
+
 double ceil(double x);
 float ceilf(float x);
-long double ceill(long double x);
+
 double floor(double x);
 float floorf(float x);
-long double floorl(long double x);
+
 double nearbyint(double x);
 float nearbyintf(float x);
-long double nearbyintl(long double x);
+
 double rint(double x);
 float rintf(float x);
-long double rintl(long double x);
+
 long int lrint(double x);
 long int lrintf(float x);
-long int lrintl(long double x);
+
 long long int llrint(double x);
 long long int llrintf(float x);
-long long int llrintl(long double x);
+
 double round(double x);
 float roundf(float x);
-long double roundl(long double x);
+
 long int lround(double x);
 long int lroundf(float x);
-long int lroundl(long double x);
+
 long long int llround(double x);
 long long int llroundf(float x);
-long long int llroundl(long double x);
+
 double trunc(double x);
 float truncf(float x);
-long double truncl(long double x);
+
 double fmod(double x, double y);
 float fmodf(float x, float y);
-long double fmodl(long double x, long double y);
+
 double remainder(double x, double y);
 float remainderf(float x, float y);
-long double remainderl(long double x, long double y);
+
 double remquo(double x, double y, int *quo);
 float remquof(float x, float y, int *quo);
-long double remquol(long double x, long double y, int *quo);
+
 double copysign(double x, double y);
 float copysignf(float x, float y);
-long double copysignl(long double x, long double y);
+
 double nan(const char *tagp);
 float nanf(const char *tagp);
-long double nanl(const char *tagp);
+
 double nextafter(double x, double y);
 float nextafterf(float x, float y);
-long double nextafterl(long double x, long double y);
-double nexttoward(double x, long double y);
-float nexttowardf(float x, long double y);
-long double nexttowardl(long double x, long double y);
+
 double fdim(double x, double y);
 float fdimf(float x, float y);
-long double fdiml(long double x, long double y);
+
 double fmax(double x, double y);
 float fmaxf(float x, float y);
-long double fmaxl(long double x, long double y);
+
 double fmin(double x, double y);
 float fminf(float x, float y);
-long double fminl(long double x, long double y);
+
 double fma(double x, double y, double z);
 float fmaf(float x, float y, float z);
-long double fmal(long double x, long double y, long double z);
+