diff --git a/.gitignore b/.gitignore
index ed93eb3..ab4e333 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 cache
 vgcore.*
 libnoja.a
-noja
\ No newline at end of file
+noja
+*.gcov
\ No newline at end of file
diff --git a/build_tests.sh b/build_tests.sh
index 7e83d90..ae0ef57 100755
--- a/build_tests.sh
+++ b/build_tests.sh
@@ -1,13 +1,12 @@
 FILES="tests/assembler_test.c    \
-       src/assembler/assembler.c \
-       src/common/executable.c   \
-       src/utils/error.c         \
-       src/utils/source.c        \
-       src/utils/bpalloc.c       \
-       src/utils/promise.c       \
-       src/utils/labellist.c     \
-       src/utils/bucketlist.c"
-
-gcc $FILES -o build/assembler_test_cov -Wall -Wextra -g --coverage
-gcc $FILES -o build/assembler_test -Wall -Wextra -g
+       src/noja/assembler/assembler.c \
+       src/noja/common/executable.c   \
+       src/noja/utils/error.c         \
+       src/noja/utils/source.c        \
+       src/noja/utils/bpalloc.c       \
+       src/noja/utils/promise.c       \
+       src/noja/utils/labellist.c     \
+       src/noja/utils/bucketlist.c"
 
+gcc $FILES -o assembler_test_cov -Wall -Wextra -g --coverage
+gcc $FILES -o assembler_test     -Wall -Wextra -g
diff --git a/examples/bubble_sort.njbc b/examples/bubble_sort.njbc
new file mode 100644
index 0000000..f0009e8
--- /dev/null
+++ b/examples/bubble_sort.njbc
@@ -0,0 +1,171 @@
+    PUSHFUN  copy, 1;
+    ASS      "copy";
+    POP      1;
+    JUMP     copy_end;
+
+copy:
+    ASS      "L";
+    POP      1;
+    PUSHLST  0;
+    ASS      "L2";
+    POP      1;
+    PUSHINT  0;
+    ASS     "i";
+    POP     1;
+    PUSHVAR "i";
+    PUSHVAR "L";
+    PUSHVAR "count";
+    CALL    1, 1;
+    LSS;
+    JUMPIFNOTANDPOP 31; 
+    PUSHVAR "L";
+    PUSHVAR "i";
+    SELECT;
+    PUSHVAR "L2";
+    PUSHVAR "i";
+    INSERT2;
+    POP     1;
+    PUSHVAR "i";
+    PUSHINT 1;
+    ADD;
+    ASS     "i";
+    POP     1;
+    JUMP    12;
+    PUSHVAR "L2";
+    RETURN  1;
+    RETURN  0;
+
+copy_end:
+    PUSHFUN bubble_sort, 2;
+    ASS     "bubble_sort";
+    POP     1;
+    JUMP    bubble_sort_end;
+
+bubble_sort:
+    ASS     "less";
+    POP     1;
+    ASS     "L";
+    POP     1;
+    PUSHVAR "less";
+    PUSHNNE;
+    EQL;
+    JUMPIFNOTANDPOP default_less_cb_end;
+    PUSHFUN 50, 2;
+    ASS     "less";
+    POP     1;
+    JUMP    default_less_cb_end;
+
+default_less_cb:
+    ASS     "b";
+    POP     1;
+    ASS     "a";
+    POP     1;
+    PUSHVAR "a"; 
+    PUSHVAR "b";
+    LSS;
+    RETURN  1;
+    RETURN  0;
+
+default_less_cb_end:
+    PUSHVAR "L";
+    PUSHVAR "copy"; 
+    CALL    1, 1;
+    ASS     "L"; 
+    POP     1;
+
+outer_loop_start:
+    PUSHFLS;
+    ASS     "swapped";
+    POP     1;
+    PUSHINT 0;
+    ASS     "i";
+    POP     1;
+
+inner_loop_start:
+    PUSHVAR "i";
+    PUSHVAR "L";
+    PUSHVAR "count";
+    CALL    1, 1;
+    PUSHINT 1;
+    SUB;
+    LSS;
+    PUSHVAR "swapped";
+    NOT;
+    AND;
+    JUMPIFNOTANDPOP outer_loop_end;
+    PUSHVAR "L";
+    PUSHVAR "i";
+    SELECT;
+    PUSHVAR "L";
+    PUSHVAR "i";
+    PUSHINT 1;
+    ADD;
+    SELECT;
+    PUSHVAR "less";
+    CALL 2, 1;
+    JUMPIFNOTANDPOP if_branch_end;
+    PUSHTRU;
+    ASS "swapped";
+    POP 1;
+    PUSHVAR "L";
+    PUSHVAR "i";
+    PUSHINT 1;
+    ADD;
+    SELECT;
+    ASS "tmp";
+    POP 1;
+    PUSHVAR "L";
+    PUSHVAR "i";
+    SELECT;
+    PUSHVAR "L";
+    PUSHVAR "i";
+    PUSHINT 1;
+    ADD;
+    INSERT2;
+    POP     1;
+    PUSHVAR "tmp";
+    PUSHVAR "L";
+    PUSHVAR "i";
+    INSERT2;
+    POP     1;
+
+if_branch_end:
+    PUSHVAR "i";
+    PUSHINT 1;
+    ADD;
+    ASS     "i";
+    POP     1;
+    JUMP    inner_loop_start;
+
+outer_loop_end:
+    PUSHVAR      "swapped";
+    JUMPIFANDPOP outer_loop_start;
+    PUSHVAR      "L";
+    RETURN       1;
+    RETURN       0;
+
+bubble_sort_end:
+    PUSHLST 5;
+    PUSHINT 0;
+    PUSHINT 3;
+    INSERT;
+    PUSHINT 1;
+    PUSHINT 2;
+    INSERT;
+    PUSHINT 2;
+    PUSHINT 1;
+    INSERT;
+    PUSHINT 3;
+    PUSHINT 6;
+    INSERT;
+    PUSHINT 4;
+    PUSHINT 0;
+    PUSHINT 2;
+    SUB;
+    INSERT;
+    PUSHVAR "bubble_sort";
+    CALL    1, 1;
+    PUSHVAR "print";
+    CALL    1, 1;
+    POP     1;
+    RETURN  0;
diff --git a/examples/hello-world.njbc b/examples/hello-world.njbc
new file mode 100644
index 0000000..f37fe92
--- /dev/null
+++ b/examples/hello-world.njbc
@@ -0,0 +1,5 @@
+PUSHSTR "Hello, world!\n";
+PUSHVAR "print";
+CALL    1, 1;
+POP     1;
+RETURN  0;
diff --git a/makefile b/makefile
index dfd7447..70a377a 100644
--- a/makefile
+++ b/makefile
@@ -57,8 +57,8 @@ LFLAGS_DEBUG =
 CFLAGS_RELEASE = -DNDEBUG -O3
 LFLAGS_RELEASE =
 
-CFLAGS_COVERAGE_GCC = 
-LFLAGS_COVERAGE_GCC = --coverage
+CFLAGS_COVERAGE_GCC = -fprofile-arcs -ftest-coverage
+LFLAGS_COVERAGE_GCC = -lgcov
 CFLAGS_COVERAGE_CLANG = -fprofile-instr-generate -fcoverage-mapping
 LFLAGS_COVERAGE_CLANG =
 # NOTE: To support BUILD_MODE=COVERAGE for a new compiler,
@@ -135,4 +135,4 @@ install: $(LIB) $(CLI)
 clean:
 	rm -rf $(OBJDIR)
 	rm  -f $(LIB)
-	rm  -f $(CLI)
\ No newline at end of file
+	rm  -f $(CLI)
diff --git a/src/cli/main.c b/src/cli/main.c
index 42bb96b..b76f92c 100644
--- a/src/cli/main.c
+++ b/src/cli/main.c
@@ -39,7 +39,9 @@ static const char usage[] =
 	"    $ noja run file.noja\n"
 	"    $ noja run inline \"print('some noja code');\"\n"
 	"    $ noja dis file.noja\n"
-	"    $ noja dis inline \"print('some noja code');\"\n";
+	"    $ noja dis inline \"print('some noja code');\"\n"
+	"    $ noja asm file.noja\n"
+	"    $ noja asm inline \"PUSHINT 5; PUSHFLT 1.0; ADD; POP 1;\"\n";
 
 int main(int argc, char **argv)
 {
@@ -76,6 +78,30 @@ int main(int argc, char **argv)
 			r = NOJA_runFile(argv[2]);
 		return r ? 0 : -1;
 	}
+
+	if(!strcmp(argv[1], "asm"))
+	{
+		if(argc == 2)
+		{
+			fprintf(stderr, "Error: Missing source file.\n");
+			return -1;
+		}
+
+		_Bool r;
+
+		if(!strcmp(argv[2], "inline"))
+		{
+			if(argc == 3)
+			{
+				fprintf(stderr, "Error: Missing source string.\n");
+				return -1;
+			}
+			r = NOJA_runAssemblyString(argv[3]);
+		}
+		else
+			r = NOJA_runAssemblyFile(argv[2]);
+		return r ? 0 : -1;
+	}
 	
 	if(!strcmp(argv[1], "dis"))
 	{
@@ -111,4 +137,4 @@ int main(int argc, char **argv)
 	fprintf(stderr, "Error: Incorrect usage.\n\n");
 	fprintf(stderr, usage);
 	return -1;
-}
\ No newline at end of file
+}
diff --git a/src/noja/assembler/assembler.c b/src/noja/assembler/assembler.c
deleted file mode 100644
index f833e86..0000000
--- a/src/noja/assembler/assembler.c
+++ /dev/null
@@ -1,389 +0,0 @@
-#include <ctype.h>
-#include <limits.h>
-#include <string.h>
-#include <assert.h>
-#include "../utils/error.h"
-#include "../utils/source.h"
-#include "../utils/labellist.h"
-#include "../common/executable.h"
-
-typedef struct {
-    const char *str;
-    size_t len;
-    size_t cur;
-} Context;
-
-static void skipIdentifier(Context *ctx)
-{
-    while(ctx->cur < ctx->len && (isalpha(ctx->str[ctx->cur]) || isdigit(ctx->str[ctx->cur]) || ctx->str[ctx->cur] == '_'))
-        ctx->cur += 1;
-}
-
-static void skipSpaces(Context *ctx)
-{
-    while(ctx->cur < ctx->len && isspace(ctx->str[ctx->cur]))
-        ctx->cur += 1;
-}
-
-typedef struct {
-    size_t offset;
-    size_t length;
-} Slice;
-
-static bool parseLabelAndOpcode(Context *ctx, bool *no_label, 
-                                Slice *label, Slice *opcode, 
-                                Error *error)
-{
-    assert(ctx != NULL && no_label != NULL 
-        && label != NULL && opcode != NULL);
-
-    // NOTE: This function must start at
-    // the first byte of the label or
-    // opcode. All whitespace must be
-    // consumed by the caller. 
-
-    // Now we expect either a label and an
-    // opcode, or just an opcode
-    //
-    //   <label>: <opcode> ..operands..
-    //   <opcode> ..operands..
-    //
-    // Labels and opcodes can bot contain
-    // digits, letters and underscores.
-
-    Slice label_or_opcode;
-    {
-        char c = ctx->str[ctx->cur];
-        if(!isalpha(c) && c != '_') {
-            // ERROR: Missing opcode
-            Error_Report(error, 0, "Missing opcode");
-        }
-        
-        label_or_opcode.offset = ctx->cur;
-        skipIdentifier(ctx);
-        label_or_opcode.length = ctx->cur - label_or_opcode.offset;
-
-        assert(label_or_opcode.length > 0);
-    }
-
-    // Get the character after the label or opcode
-    // (ignoring whitespace), and if it's a ':',
-    // then it was a label.
-    skipSpaces(ctx);
-    if(ctx->cur < ctx->len && ctx->str[ctx->cur] == ':') {
-
-        // Skip the ':' and the whitespace after it.
-        ctx->cur += 1;
-        skipSpaces(ctx);
-
-        if(ctx->cur == ctx->len || (!isalpha(ctx->str[ctx->cur]) && ctx->str[ctx->cur] != '_')) {
-            Error_Report(error, 0, "Missing opcode after label");
-            return false;
-        }
-
-        // Now the opcode is expected.
-        opcode->offset = ctx->cur;
-        skipIdentifier(ctx);
-        opcode->length = ctx->cur - opcode->offset;
-        assert(opcode->length > 0);
-
-        *no_label = false;
-        *label = label_or_opcode;
-        skipSpaces(ctx);
-    } else {
-        *no_label = true;
-        *opcode = label_or_opcode;
-    }
-    return true;
-}
-
-static bool parseStringOperand(Context *ctx, Error *error, BPAlloc *alloc, Operand *op)
-{
-    // Skip the first double quote.
-    assert(ctx->cur < ctx->len && ctx->str[ctx->cur] == '"');
-    ctx->cur += 1;
-
-    size_t literal_offset = ctx->cur;
-
-    // For now do a dumb copy into the buffer
-    // without considering special characters.
-    while(ctx->cur < ctx->len && ctx->str[ctx->cur] != '"')
-        ctx->cur += 1;
-
-    if(ctx->cur == ctx->len) {
-        Error_Report(error, 0, "End of source inside a string literal");
-        return false;
-    }
-
-    // Skip the ending double quotes.
-    assert(ctx->cur < ctx->len && ctx->str[ctx->cur] == '"');
-    ctx->cur += 1;
-
-    size_t literal_length = ctx->cur - literal_offset;
-
-    char *copy = BPAlloc_Malloc(alloc, literal_length+1);
-    if(copy == NULL) {
-        Error_Report(error, 1, "No memory");
-        return false;
-    }
-
-    memcpy(copy, ctx->str + literal_offset, literal_length);
-    copy[literal_length] = '\0';
-
-    op->type = OPTP_STRING;
-    op->as_string = copy;
-    return true;
-}
-
-static bool parseIntegerOperand(Context *ctx, Error *error, Operand *op)
-{
-    // It's ensured by the caller that the cursor is
-    // pointing to a sequence of one or more digits
-    // NOT followed by a dot and a digit after that
-    // (so this is an integer for sure, not a float).
-    assert(ctx->cur < ctx->len && isdigit(ctx->str[ctx->cur]));
-
-    long long int buffer = 0;
-    do {
-        // Transform each digit into it's integer value.
-        int d = ctx->str[ctx->cur] - '0';
-        assert(d >= 0 && d <= 9);
-
-        // Will this overflow?
-        if(buffer > (LLONG_MAX - d) / 10) {
-            Error_Report(error, 0, "Integer literal is too big to be represented in %d bits", 8*sizeof(buffer));
-            return false;
-        }
-
-        buffer = buffer * 10 + d;
-        ctx->cur += 1;
-    } while(ctx->cur < ctx->len && isdigit(ctx->str[ctx->cur]));
-
-    // Not a float!
-
-    op->type = OPTP_INT;
-    op->as_int = buffer;
-    return true;
-}
-
-static bool parseFloatingOperand(Context *ctx, Error *error, Operand *op)
-{   
-    (void) error; // At the moment this function doesn't report
-                  // any error. This may change when overflows
-                  // and underflows are detected.
-
-    // It's ensured by the caller that the cursor is
-    // pointing to a sequence of one or more digits
-    // followed by a dot and a digit after that.
-    assert(ctx->cur < ctx->len && isdigit(ctx->str[ctx->cur]));
-
-    double buffer = 0;
-    do {
-        // Transform each digit into it's integer value.
-        int d = ctx->str[ctx->cur] - '0';
-        assert(d >= 0 && d <= 9);
-
-        // Should overflow be checked?
-        buffer = buffer * 10 + d;
-
-        ctx->cur += 1;
-    } while(ctx->str[ctx->cur] != '.');
-
-    assert(ctx->cur+1 < ctx->len && ctx->str[ctx->cur] == '.' && isdigit(ctx->str[ctx->cur+1]));
-
-    double q = 1;
-    do {
-        // Transform each digit into it's integer value.
-        int d = ctx->str[ctx->cur] - '0';
-        assert(d >= 0 && d <= 9);
-
-        buffer += q * d;
-
-        ctx->cur += 1;
-    } while(ctx->cur < ctx->len && isdigit(ctx->str[ctx->cur]));
-
-    op->type = OPTP_FLOAT;
-    op->as_float = buffer;
-    return true;
-}
-
-static bool parseOperands(Context *ctx, BPAlloc *alloc, Error *error, 
-                          LabelList *list, Operand *opv, int *opc, int opc_max)
-{
-    // NOTE: The whitespace before the first operand must
-    // be consumed by the caller.
-
-    if(ctx->cur < ctx->len && ctx->str[ctx->cur] != ';')
-        while(1) {
-
-            Operand op;
-
-            char c = ctx->str[ctx->cur];
-            if(c == '"') {
-            
-                if(!parseStringOperand(ctx, error, alloc, &op))
-                    return false;
-            
-            } else if(isdigit(c)) {
-            
-                /* Integer or float operand */
-
-                size_t k = ctx->cur;
-                while(k < ctx->len && isdigit(ctx->str[k]))
-                    k += 1;
-                
-                bool ok;
-                if(k+1 >= ctx->len || ctx->str[k] != '.' || !isdigit(ctx->str[k+1]))
-                    ok = parseIntegerOperand(ctx, error, &op);
-                else
-                    ok = parseFloatingOperand(ctx, error, &op);
-                
-                if(!ok)
-                    return false;
-
-            } else if(isalpha(c) || c == '_') {
-                
-                /* Label */
-                size_t offset = ctx->cur;
-                skipIdentifier(ctx);
-                size_t length = ctx->cur - offset;
-
-                Promise *promise = LabelList_GetLabel(list, ctx->str + offset, length);
-                if(promise == NULL) {
-                    Error_Report(error, 1, "No memory");
-                    return false;
-                }
-
-                op.type = OPTP_PROMISE;
-                op.as_promise = promise;
-
-            } else {
-                // ERROR: Unexpected character
-                Error_Report(error, 0, "Unexpected character '%c'", c);
-                return false;
-            }
-
-            if(*opc == opc_max) {
-                Error_Report(error, 0, "Too many operands");
-                return false;
-            }
-            opv[*opc] = op;
-            *opc += 1;
-            // Now prepare for the next operand
-            skipSpaces(ctx);
-
-            if(ctx->cur == ctx->len || ctx->str[ctx->cur] == ';')
-                break;
-
-            c = ctx->str[ctx->cur];
-            if(c != ',') {
-                Error_Report(error, 0, "Unexpected character '%c' (',' or ';' were expected)", c);
-                return false;
-            }
-
-            // Skip the comma
-            ctx->cur += 1;
-
-            // Skip the spaces before the next operand
-            skipSpaces(ctx);
-        }
-    assert(ctx->cur == ctx->len || ctx->str[ctx->cur] == ';');
-    return true;
-}
-
-Executable *assemble(Source *src, Error *error)
-{
-    Executable *exe = NULL;
-
-    BPAlloc *alloc = BPAlloc_Init(-1);
-    if(alloc == NULL) {
-        Error_Report(error, 1, "No memory");
-        return NULL;
-    }
-
-    LabelList *list = LabelList_New(alloc);
-    if(list == NULL) {
-        Error_Report(error, 1, "No memory");
-        BPAlloc_Free(alloc);
-        return NULL;
-    }
-
-    ExeBuilder *builder = ExeBuilder_New(alloc);
-    if(builder == NULL) {
-        Error_Report(error, 1, "No memory");
-        LabelList_Free(list);
-        BPAlloc_Free(alloc);
-        return NULL;
-    }
-
-    Context ctx = { 
-        .str = Source_GetBody(src),
-        .len = Source_GetSize(src),
-        .cur = 0,
-    };
-    while(1) {
-
-        skipSpaces(&ctx);
-
-        if(ctx.cur == ctx.len)
-            break;
-
-        bool no_label;
-        Slice label, opcode_name;
-
-        if(!parseLabelAndOpcode(&ctx, &no_label, &label, &opcode_name, error))
-            goto done;
-
-        // If a label was defined, add it to the list.
-        if(no_label == false) {
-            long long int value = ExeBuilder_InstrCount(builder);
-            if(!LabelList_SetLabel(list, ctx.str + label.offset, label.length, value)) {
-                Error_Report(error, 1, "Out of memory");
-                goto done;
-            }
-        }
-
-        // Check that the opcode is valid (at this
-        // point it's just an unchecked identifier)
-        Opcode opcode;
-        const char *name = ctx.str + opcode_name.offset;
-        if(!Executable_GetOpcodeBinaryFromName(name, opcode_name.length, &opcode)) {
-            Error_Report(error, 0, "Opcode %.*s doesn't exist", (int) opcode_name.length, name);
-            goto done;
-        }
-
-        /* Parse operands */
-        // (whitespace was already skipped)
-
-        Operand opv[8];
-        int     opc = 0;
-
-        if(!parseOperands(&ctx, alloc, error, list, opv, &opc, sizeof(opv)/sizeof(opv[0])))
-            goto done;
-
-        // The operand list ended with a ';' or the
-        // end of the file. If the file didn't end,
-        // then the ';' must be consumed.
-        assert(ctx.cur == ctx.len || ctx.str[ctx.cur] == ';');
-        if(ctx.cur < ctx.len) ctx.cur += 1;
-
-        if(!ExeBuilder_Append(builder, error, opcode, opv, opc, opcode_name.offset, opcode_name.length))
-            goto done;
-    }
-
-    size_t unresolved_count = LabelList_GetUnresolvedCount(list);
-    if(unresolved_count > 0) {
-        Error_Report(error, 0, "%d unresolved labels", unresolved_count);
-        goto done;
-    }
-
-    exe = ExeBuilder_Finalize(builder, error);
-
-    if(exe != NULL)
-        (void) Executable_SetSource(exe, src);
-
-done:
-    LabelList_Free(list);
-    BPAlloc_Free(alloc);
-    return exe;
-}
diff --git a/src/noja/assembler/assembler.h b/src/noja/assembler/assembler.h
deleted file mode 100644
index 6170966..0000000
--- a/src/noja/assembler/assembler.h
+++ /dev/null
@@ -1,7 +0,0 @@
-#ifndef ASSEMBLE_H
-#define ASSEMBLE_H
-#include "../utils/error.h"
-#include "../utils/source.h"
-#include "../common/executable.h"
-Executable *assemble(Source *src, Error *error);
-#endif /* ASSEMBLE_H */
\ No newline at end of file
diff --git a/src/noja/noja.c b/src/noja/noja.c
index e774563..98e0170 100644
--- a/src/noja/noja.c
+++ b/src/noja/noja.c
@@ -4,6 +4,7 @@
 #include "utils/source.h"
 #include "compiler/parse.h"
 #include "compiler/compile.h"
+#include "assembler/assemble.h"
 #include "builtins/basic.h"
 #include "noja.h"
 
@@ -79,13 +80,8 @@ static Executable *build(Source *src)
     return exe;
 }
 
-static _Bool interpret(Source *src)
+static _Bool interpret(Executable *exe)
 {
-    Executable *exe = build(src);
-
-    if(exe == NULL)
-        return 0;
-
     Runtime *runt = Runtime_New(-1, 1024*1024, NULL, NULL);
 
     if(runt == NULL)
@@ -95,7 +91,6 @@ static _Bool interpret(Source *src)
         Error_Report(&error, 1, "Couldn't initialize runtime");
         print_error(NULL, &error);
         Error_Free(&error);
-        Executable_Free(exe);
         return 0;
     }
 
@@ -115,7 +110,6 @@ static _Bool interpret(Source *src)
         assert(error.base.occurred == 1);
         print_error(NULL, (Error*) &error);
         RuntimeError_Free(&error);
-        Executable_Free(exe);
         Runtime_Free(runt);
         return 0;
     }
@@ -143,8 +137,6 @@ static _Bool interpret(Source *src)
     }
 
     Runtime_Free(runt);
-    Executable_Free(exe);
-
     return retc > -1;
 }
 
@@ -174,8 +166,14 @@ static _Bool interpret_file(const char *file)
         return 0;
     }
 
-    _Bool r = interpret(src);
+    Executable *exe = build(src);
 
+    if(exe == NULL)
+        return 0;
+
+    _Bool r = interpret(exe);
+
+    Executable_Free(exe);
     Source_Free(src);
     return r;
 }
@@ -195,12 +193,80 @@ static _Bool interpret_code(const char *code)
         return 0;
     }
 
-    _Bool r = interpret(src);
+    Executable *exe = build(src);
 
+    if(exe == NULL)
+        return 0;
+
+    _Bool r = interpret(exe);
+
+    Executable_Free(exe);
     Source_Free(src);
     return r;
 }
 
+static _Bool interpret_asm_file(const char *file)
+{
+    Error error;
+    Error_Init(&error);
+    
+    Source *src = Source_FromFile(file, &error);
+
+    if(src == NULL)
+    {
+        assert(error.occurred == 1);
+        print_error(NULL, &error);
+        Error_Free(&error);
+        return 0;
+    }
+
+    Executable *exe = assemble(src, &error);
+    if(exe == NULL) {
+        print_error("Assemblation", &error);
+        Source_Free(src);
+        Error_Free(&error);
+        return 0;
+    }
+
+    _Bool r = interpret(exe);
+
+    Executable_Free(exe);
+    Source_Free(src);
+    Error_Free(&error);
+    return r;
+}
+
+static _Bool interpret_asm_code(const char *code)
+{
+    Error error;
+    Error_Init(&error);
+    
+    Source *src = Source_FromString(NULL, code, -1, &error);
+
+    if(src == NULL)
+    {
+        assert(error.occurred);
+        print_error(NULL, &error);
+        Error_Free(&error);
+        return 0;
+    }
+
+    Executable *exe = assemble(src, &error);
+    if(exe == NULL) {
+        print_error("Assemblation", &error);
+        Source_Free(src);
+        Error_Free(&error);
+        return 0;
+    }
+
+    _Bool r = interpret(exe);
+
+    Executable_Free(exe);
+    Source_Free(src);
+    Error_Free(&error);
+    return r;
+}
+
 static _Bool disassemble_file(const char *file)
 {
     Error error;
@@ -261,4 +327,14 @@ _Bool NOJA_dumpFileBytecode(const char *file)
 _Bool NOJA_dumpStringBytecode(const char *str)
 {
     return disassemble_code(str);
+}
+
+_Bool NOJA_runAssemblyFile(const char *file)
+{
+    return interpret_asm_file(file);
+}
+
+_Bool NOJA_runAssemblyString(const char *str)
+{
+    return interpret_asm_code(str);
 }
\ No newline at end of file
diff --git a/src/noja/noja.h b/src/noja/noja.h
index a7de41c..a4979f8 100644
--- a/src/noja/noja.h
+++ b/src/noja/noja.h
@@ -1,7 +1,9 @@
 #ifndef NOJA_H
 #define NOJA_H
+_Bool NOJA_runFile  (const char *file);
 _Bool NOJA_runString(const char *str);
-_Bool NOJA_runFile(const char *file);
+_Bool NOJA_runAssemblyFile(const char *file);
+_Bool NOJA_runAssemblyString(const char *str);
 _Bool NOJA_dumpFileBytecode(const char *file);
 _Bool NOJA_dumpStringBytecode(const char *str);
 #endif /* NOJA_H */
\ No newline at end of file
diff --git a/tests/assembler_test.c b/tests/assembler_test.c
index 9e57fd5..23c6676 100644
--- a/tests/assembler_test.c
+++ b/tests/assembler_test.c
@@ -1,7 +1,7 @@
 #include <stdlib.h>
 #include <stdbool.h>
-#include "../src/utils/bpalloc.h"
-#include "../src/assembler/assembler.h"
+#include "../src/noja/utils/bpalloc.h"
+#include "../src/noja/assembler/assembler.h"
 
 static void stopTesting_(const char *file, int line)
 {
@@ -243,6 +243,45 @@ int main()
                 },
             },
         },
+
+        // Instruction with the wrong number of arguments.
+        {
+            .line = __LINE__,
+            .text = "POS  1;",
+            .fail = true,
+        },
+
+        {
+            .line = __LINE__,
+            .text = "PUSHINT 1;"
+                    "PUSHINT 2;"
+                    "ADD;",
+            .fail = false,
+            .expected = (StaticExecutable) {
+                .instr_count = 3,
+                .instr_list = (StaticInstruction[]) {
+                    {
+                        .opcode = OPCODE_PUSHINT,
+                        .operands = (Operand[]) {
+                            { OPTP_INT, .as_int = 1, }
+                        },
+                        .operand_count = 1,
+                    },
+                    {
+                        .opcode = OPCODE_PUSHINT,
+                        .operands = (Operand[]) {
+                            { OPTP_INT, .as_int = 2, }
+                        },
+                        .operand_count = 1,
+                    },
+                    {
+                        .opcode = OPCODE_ADD,
+                        .operands = NULL,
+                        .operand_count = 0,
+                    },
+                },
+            },
+        },
     };
 
     Error error;
@@ -262,14 +301,17 @@ int main()
         stopTestingIf(src == NULL);
 
         Executable *got_exe = assemble(src, &error);
-        
+
         if(tests[i].fail == true) {
             testCase(tests[i].line, got_exe == NULL, "Managed to assemble an invalid source");
         } else {
             Executable *exp_exe = buildExpectedExecutable(alloc, &tests[i].expected);
 
+            if(got_exe == NULL)
+                fprintf(stderr, "Build error :: %s.\n", error.message);
+
             testCase(tests[i].line, got_exe != NULL, "Failed to assemble a valid source");
-/*
+/*          
             fprintf(stderr, "== Generated ==\n");
             Executable_Dump(got_exe);
             fprintf(stderr, "\n");