diff --git a/assembler/assembler.c b/assembler/assembler.c
index 3cc0158..a5a894c 100644
--- a/assembler/assembler.c
+++ b/assembler/assembler.c
@@ -421,7 +421,7 @@ int try_match_instruction(struct assembler_state *state, char **_line) {
 		return 0;
 	} else {
 		scas_log(L_DEBUG, "Matched string '%s' to instruction '%s'", line, match->instruction->match);
-		scas_log_indent();
+		scas_log_indent += 1;
 		uint64_t instruction = match->instruction->value;
 		for (unsigned int i = 0; i < match->operands->length; ++i) {
 			operand_ref_t *ref = match->operands->items[i];
@@ -522,7 +522,7 @@ int try_match_instruction(struct assembler_state *state, char **_line) {
 		}
 		append_to_area(state->current_area, state->instruction_buffer, bytes_width);
 		state->PC += bytes_width;
-		scas_log_deindent();
+		scas_log_indent -= 1;
 		match_free(match);
 	}
 	return 1;
diff --git a/assembler/directives.c b/assembler/directives.c
index 28500a3..1986a0a 100644
--- a/assembler/directives.c
+++ b/assembler/directives.c
@@ -1503,9 +1503,9 @@ int try_handle_directive(struct assembler_state *state, char **line) {
 				(char *)stack_peek(state->file_name_stack), *(int *)stack_peek(state->line_number_stack));
 		int argc;
 		char **argv = split_directive(*line + strlen(d->match) + 1, &argc, d->delimiter);
-		scas_log_indent();
+		scas_log_indent += 1;
 		int ret = d->function(state, argv, argc);
-		scas_log_deindent();
+		scas_log_indent -= 1;
 		for (int i = 0; i < argc; i += 1) {
 			free(argv[i]);
 		}
diff --git a/include/log.h b/include/log.h
index 61bf528..cdddc30 100644
--- a/include/log.h
+++ b/include/log.h
@@ -5,9 +5,8 @@ typedef enum {
     L_DEBUG = 3,
 } scas_log_importance_t;
 
-void scas_log_init(scas_log_importance_t verbosity);
 void scas_log(scas_log_importance_t verbosity, char* format, ...);
-void scas_log_indent();
-void scas_log_deindent();
-void scas_log_set_colors(bool enabled);
 
+extern bool scas_log_colorize;
+extern scas_log_importance_t scas_log_verbosity;
+extern unsigned scas_log_indent;
diff --git a/linker/linker.c b/linker/linker.c
index 0974afe..57c4055 100644
--- a/linker/linker.c
+++ b/linker/linker.c
@@ -35,7 +35,7 @@ symbol_t *find_symbol(list_t *symbols, char *name) {
 
 void resolve_immediate_values(list_t *symbols, area_t *area, list_t *errors) {
 	scas_log(L_DEBUG, "Resolving immediate values for area '%s' at %08X", area->name, area->final_address);
-	scas_log_indent();
+	scas_log_indent += 1;
 	for (unsigned int i = 0; i < area->late_immediates->length; ++i) {
 		late_immediate_t *imm = area->late_immediates->items[i];
 		imm->instruction_address += area->final_address;
@@ -92,7 +92,7 @@ void resolve_immediate_values(list_t *symbols, area_t *area, list_t *errors) {
 			}
 		}
 	}
-	scas_log_deindent();
+	scas_log_indent -= 1;
 }
 
 /* z80 only (and possibly ez80) */
diff --git a/log.c b/log.c
index 85aa9c8..9da1473 100644
--- a/log.c
+++ b/log.c
@@ -8,9 +8,14 @@
 #include <emscripten.h>
 #endif
 
-static scas_log_importance_t v = 0;
-static unsigned indent = 0;
-static bool colored = true;
+void scas_log_default(const char *msg) {
+	fprintf(stderr, "%s", msg);
+}
+
+scas_log_importance_t scas_log_verbosity = 0;
+unsigned scas_log_indent = 0;
+bool scas_log_colorize = true;
+void (*scas_log_function)(const char *) = scas_log_default;
 
 const char *verbosity_colors[] = {
 	"", // L_SILENT
@@ -19,42 +24,34 @@ const char *verbosity_colors[] = {
 	"\x1B[1;30m", // L_DEBUG
 };
 
-void scas_log_init(scas_log_importance_t verbosity) {
-	v = verbosity;
-}
-
-void scas_log_set_colors(bool _colored) {
-	colored = _colored;
-}
-
-void scas_log_indent() {
-	++indent;
-}
-
-void scas_log_deindent() {
-	if (indent > 0) {
-		--indent;
-	}
-}
-
 void scas_log(scas_log_importance_t verbosity, char* format, ...) {
-	if (verbosity <= v && verbosity >= 0) {
-		size_t c = verbosity;
-		if (c > sizeof(verbosity_colors) / sizeof(char *)) {
-			c = sizeof(verbosity_colors) / sizeof(char *) - 1;
-		}
-		if (colored) {
-			fprintf(stderr, "%s", verbosity_colors[c]);
-		}
-		if (verbosity == L_DEBUG || verbosity == L_INFO) {
-			for (unsigned i = 0; i < indent; ++i) {
-				fprintf(stderr, "  ");
+	if (scas_log_function) {
+		if (verbosity <= scas_log_verbosity && verbosity >= 0) {
+			size_t c = verbosity;
+			if (c > sizeof(verbosity_colors) / sizeof(char *)) {
+				c = sizeof(verbosity_colors) / sizeof(char *) - 1;
+			}
+			if (scas_log_colorize) {
+				scas_log_function(verbosity_colors[c]);
+			}
+			if (verbosity == L_DEBUG || verbosity == L_INFO) {
+				for (unsigned i = 0; i < scas_log_indent; ++i) {
+					scas_log_function("  ");
+				}
+			}
+			va_list args;
+			va_start(args, format);
+			int length = vsnprintf(NULL, 0, format, args);
+			va_end(args);
+			if (length > 0) {
+				va_start(args, format);
+				char *buf = malloc(length + 1);
+				vsnprintf(buf, length, format, args);
+				va_end(args);
+				scas_log_function(buf);
+				free(buf);
+				scas_log_function(scas_log_colorize ? "\n\x1B[0m" : "\n");
 			}
 		}
-		va_list args;
-		va_start(args, format);
-		vfprintf(stderr, format, args);
-		va_end(args);
-		fprintf(stderr, "%s\n", colored ? "\x1B[0m" : "");
 	}
 }
diff --git a/scas/main.c b/scas/main.c
index bbea13b..49043e3 100644
--- a/scas/main.c
+++ b/scas/main.c
@@ -43,7 +43,6 @@ void init_scas_runtime() {
 		strcpy(scas_runtime.include_path, "./");
 	}
 	scas_runtime.linker_script = NULL;
-	scas_runtime.verbosity = L_SILENT;
 
 	scas_runtime.options.explicit_export = false;
 	// TODO: reenable
@@ -166,7 +165,7 @@ void parse_arguments(int argc, char **argv) {
 				int j;
 				for (j = 1; argv[i][j] != '\0'; ++j) {
 					if (argv[i][j] == 'v') {
-						scas_runtime.verbosity++;
+						scas_log_verbosity++;
 					} else {
 						scas_log(L_ERROR, "Invalid option %s", argv[i]);
 						exit(1);
@@ -263,8 +262,8 @@ list_t *split_include_path() {
 
 int main(int argc, char **argv) {
 	init_scas_runtime();
+	scas_log_verbosity = L_SILENT;
 	parse_arguments(argc, argv);
-	scas_log_init(scas_runtime.verbosity);
 	validate_scas_runtime();
 	instruction_set_t *instruction_set = find_inst();
 	if (instruction_set == NULL) {
@@ -279,7 +278,7 @@ int main(int argc, char **argv) {
 	list_t *objects = create_list();
 	for (unsigned int i = 0; i < scas_runtime.input_files->length; ++i) {
 		scas_log(L_INFO, "Assembling input file: '%s'", scas_runtime.input_names->items[i]);
-		scas_log_indent();
+		scas_log_indent += 1;
 		FILE *f = scas_runtime.input_files->items[i];
 		char magic[7];
 		bool is_object = false;
@@ -308,7 +307,7 @@ int main(int argc, char **argv) {
 					errors->length, warnings->length, scas_runtime.input_names->items[i]);
 		}
 		list_add(objects, o);
-		scas_log_deindent();
+		scas_log_indent -= 1;
 	}
 
 	if ((scas_runtime.jobs & LINK) == LINK) {
diff --git a/scdump/main.c b/scdump/main.c
index 399fda1..e8d07c2 100644
--- a/scdump/main.c
+++ b/scdump/main.c
@@ -76,7 +76,7 @@ void dump_area(area_t *a) {
 		for (unsigned int i = 0; i < a->source_map->length; ++i) {
 			source_map_t *map = a->source_map->items[i];
 			scas_log(L_INFO, "Source file '%s'", map->file_name);
-			scas_log_indent();
+			scas_log_indent += 1;
 			for (unsigned int j = 0; j < map->entries->length; ++j) {
 				source_map_entry_t *entry = map->entries->items[j];
 				symbol_t *label = find_label(entry->address, a);
@@ -90,19 +90,19 @@ void dump_area(area_t *a) {
 						map->file_name, entry->line_number,
 						entry->source_code);
 			}
-			scas_log_deindent();
+			scas_log_indent -= 1;
 		}
 	}
 	if (runtime.dump_private_symbols || runtime.dump_public_symbols) {
 		/* TODO: Distinguish between private/public */
 		scas_log(L_INFO, "Symbols defined:");
-		scas_log_indent();
+		scas_log_indent += 1;
 		for (unsigned int i = 0; i < a->symbols->length; ++i) {
 			symbol_t *sym = a->symbols->items[i];
 			scas_log(L_INFO, "'%s' == 0x%08X (%s)", sym->name, sym->value,
 					sym->type == SYMBOL_LABEL ? "Label" : "Equate");
 		}
-		scas_log_deindent();
+		scas_log_indent -= 1;
 	}
 	if (runtime.dump_references) {
 		scas_log(L_INFO, "Unresolved references:");
@@ -130,8 +130,8 @@ int main(int argc, char **argv) {
 	if (!parse_arguments(argc, argv)) {
 		return 1;
 	}
-	scas_log_init(L_INFO);
-	scas_log_set_colors(false);
+	scas_log_verbosity = L_INFO;
+	scas_log_colorize = false;
 	for (unsigned int i = 0; i < runtime.input_files->length; ++i) {
 		FILE *f;
 		if (strcasecmp(runtime.input_files->items[i], "-") == 0) {
diff --git a/scwrap/main.c b/scwrap/main.c
index b9ab580..a525d7c 100644
--- a/scwrap/main.c
+++ b/scwrap/main.c
@@ -37,7 +37,8 @@ int main(int argc, char **argv) {
 	if (!parse_arguments(argc, argv)) {
 		return 1;
 	}
-	scas_log_init(L_INFO);
+
+	scas_log_verbosity = L_INFO;
 
 	object_t *o = create_object();
 	area_t *a = create_area("DATA");