diff --git a/src/holt59/aoc/2022/day12.py b/src/holt59/aoc/2022/day12.py
index f4811a0..f6427a5 100644
--- a/src/holt59/aoc/2022/day12.py
+++ b/src/holt59/aoc/2022/day12.py
@@ -97,7 +97,12 @@ def neighbors(
 
 
 class Solver(BaseSolver):
-    def print_path(self, path: list[tuple[int, int]], n_rows: int, n_cols: int) -> None:
+    def print_path(
+        self, name: str, path: list[tuple[int, int]], n_rows: int, n_cols: int
+    ) -> None:
+        if not self.files:
+            return
+
         end = path[-1]
 
         graph = [["." for _c in range(n_cols)] for _r in range(n_rows)]
@@ -118,8 +123,11 @@ class Solver(BaseSolver):
             else:
                 assert False, "{} -> {} infeasible".format(path[i], path[i + 1])
 
-        for row in graph:
-            self.logger.info("".join(row))
+        self.files.create(
+            f"graph_{name}.txt",
+            "\n".join("".join(row) for row in graph).encode(),
+            text=True,
+        )
 
     def solve(self, input: str) -> Iterator[Any]:
         lines = input.splitlines()
@@ -157,7 +165,7 @@ class Solver(BaseSolver):
         path_1 = make_path(parents_1, start, end)
         assert path_1 is not None
 
-        self.print_path(path_1, n_rows=len(grid), n_cols=len(grid[0]))
+        self.print_path("answer1", path_1, n_rows=len(grid), n_cols=len(grid[0]))
         yield lengths_1[end] - 1
 
         lengths_2, _ = dijkstra(
diff --git a/src/holt59/aoc/2022/day14.py b/src/holt59/aoc/2022/day14.py
index 4603157..4daa710 100644
--- a/src/holt59/aoc/2022/day14.py
+++ b/src/holt59/aoc/2022/day14.py
@@ -67,13 +67,16 @@ def flow(
 
 
 class Solver(BaseSolver):
-    def print_blocks(self, blocks: dict[tuple[int, int], Cell]):
+    def print_blocks(self, name: str, blocks: dict[tuple[int, int], Cell]):
         """
         Print the given set of blocks on a grid.
 
         Args:
             blocks: Set of blocks to print.
         """
+        if not self.files:
+            return
+
         x_min, y_min, x_max, y_max = (
             min(x for x, _ in blocks),
             0,
@@ -81,12 +84,16 @@ class Solver(BaseSolver):
             max(y for _, y in blocks),
         )
 
-        for y in range(y_min, y_max + 1):
-            self.logger.info(
+        self.files.create(
+            f"blocks_{name}.txt",
+            "\n".join(
                 "".join(
                     str(blocks.get((x, y), Cell.AIR)) for x in range(x_min, x_max + 1)
                 )
-            )
+                for y in range(y_min, y_max + 1)
+            ).encode(),
+            True,
+        )
 
     def solve(self, input: str) -> Iterator[Any]:
         lines = [line.strip() for line in input.splitlines()]
@@ -115,7 +122,7 @@ class Solver(BaseSolver):
                     for y in range(y_start, y_end):
                         blocks[x, y] = Cell.ROCK
 
-        self.print_blocks(blocks)
+        self.print_blocks("start", blocks)
 
         y_max = max(y for _, y in blocks)
 
@@ -124,7 +131,7 @@ class Solver(BaseSolver):
         blocks_1 = flow(
             blocks.copy(), stop_fn=lambda x, y: y > y_max, fill_fn=lambda x, y: Cell.AIR
         )
-        self.print_blocks(blocks_1)
+        self.print_blocks("part1", blocks_1)
         yield sum(v == Cell.SAND for v in blocks_1.values())
 
         # === part 2 ===
@@ -135,5 +142,5 @@ class Solver(BaseSolver):
             fill_fn=lambda x, y: Cell.AIR if y < y_max + 2 else Cell.ROCK,
         )
         blocks_2[500, 0] = Cell.SAND
-        self.print_blocks(blocks_2)
+        self.print_blocks("part2", blocks_2)
         yield sum(v == Cell.SAND for v in blocks_2.values())
diff --git a/src/holt59/aoc/2023/day10.py b/src/holt59/aoc/2023/day10.py
index eee3f1d..8392900 100644
--- a/src/holt59/aoc/2023/day10.py
+++ b/src/holt59/aoc/2023/day10.py
@@ -83,18 +83,17 @@ class Solver(BaseSolver):
                 if (i, j) in loop_s and lines[i][j] in "|LJ":
                     cnt += 1
 
-        if self.verbose:
-            for i in range(len(lines)):
-                s = ""
-                for j in range(len(lines[0])):
-                    if (i, j) == (si, sj):
-                        s += "\033[91mS\033[0m"
-                    elif (i, j) in loop:
-                        s += lines[i][j]
-                    elif (i, j) in inside:
-                        s += "\033[92mI\033[0m"
-                    else:
-                        s += "."
-                self.logger.info(s)
+        if self.files:
+            rows = [["." for _j in range(len(lines[0]))] for _i in range(len(lines))]
+            rows[si][sj] = "\033[91mS\033[0m"
+
+            for i, j in loop:
+                rows[i][j] = lines[i][j]
+            for i, j in inside:
+                rows[i][j] = "\033[92mI\033[0m"
+
+            self.files.create(
+                "output.txt", "\n".join("".join(row) for row in rows).encode(), True
+            )
 
         yield len(inside)
diff --git a/src/holt59/aoc/2023/day16.py b/src/holt59/aoc/2023/day16.py
index a307d96..1be2783 100644
--- a/src/holt59/aoc/2023/day16.py
+++ b/src/holt59/aoc/2023/day16.py
@@ -84,9 +84,14 @@ class Solver(BaseSolver):
 
         beams = propagate(layout, (0, 0), "R")
 
-        if self.verbose:
-            for row in beams:
-                self.logger.info("".join("#" if col else "." for col in row))
+        if self.files:
+            self.files.create(
+                "beams.txt",
+                "\n".join(
+                    "".join("#" if col else "." for col in row) for row in beams
+                ).encode(),
+                True,
+            )
 
         # part 1
         yield sum(sum(map(bool, row)) for row in beams)
diff --git a/src/holt59/aoc/2023/day17.py b/src/holt59/aoc/2023/day17.py
index c4bd609..16e99ef 100644
--- a/src/holt59/aoc/2023/day17.py
+++ b/src/holt59/aoc/2023/day17.py
@@ -33,10 +33,14 @@ MAPPINGS: dict[Direction, tuple[int, int, Direction]] = {
 class Solver(BaseSolver):
     def print_shortest_path(
         self,
+        name: str,
         grid: list[list[int]],
         target: tuple[int, int],
         per_cell: dict[tuple[int, int], list[tuple[Label, int]]],
     ):
+        if not self.files:
+            return
+
         assert len(per_cell[target]) == 1
         label = per_cell[target][0][0]
 
@@ -74,8 +78,9 @@ class Solver(BaseSolver):
 
         p_grid[0][0] = f"\033[92m{grid[0][0]}\033[0m"
 
-        for row in p_grid:
-            self.logger.info("".join(row))
+        self.files.create(
+            name, "\n".join("".join(row) for row in p_grid).encode(), True
+        )
 
     def shortest_many_paths(self, grid: list[list[int]]) -> dict[tuple[int, int], int]:
         n_rows, n_cols = len(grid), len(grid[0])
@@ -129,6 +134,7 @@ class Solver(BaseSolver):
 
     def shortest_path(
         self,
+        name: str,
         grid: list[list[int]],
         min_straight: int,
         max_straight: int,
@@ -217,8 +223,7 @@ class Solver(BaseSolver):
                     ),
                 )
 
-        if self.verbose:
-            self.print_shortest_path(grid, target, per_cell)
+        self.print_shortest_path(f"shortest-path_{name}.txt", grid, target, per_cell)
 
         return per_cell[target][0][1]
 
@@ -227,7 +232,7 @@ class Solver(BaseSolver):
         estimates = self.shortest_many_paths(data)
 
         # part 1
-        yield self.shortest_path(data, 1, 3, lower_bounds=estimates)
+        yield self.shortest_path("answer_1", data, 1, 3, lower_bounds=estimates)
 
         # part 2
-        yield self.shortest_path(data, 4, 10, lower_bounds=estimates)
+        yield self.shortest_path("answer_2", data, 4, 10, lower_bounds=estimates)
diff --git a/src/holt59/aoc/2023/day20.py b/src/holt59/aoc/2023/day20.py
index 975620f..bc34b48 100644
--- a/src/holt59/aoc/2023/day20.py
+++ b/src/holt59/aoc/2023/day20.py
@@ -80,22 +80,23 @@ class Solver(BaseSolver):
                     outputs,
                 )
 
-        if self.outputs:
-            with open("./day20.dot", "w") as fp:
-                fp.write("digraph G {\n")
-                fp.write("rx [shape=circle, color=red, style=filled];\n")
-                for name, (type, outputs) in self._modules.items():
-                    if type == "conjunction":
-                        shape = "diamond"
-                    elif type == "flip-flop":
-                        shape = "box"
-                    else:
-                        shape = "circle"
-                    fp.write(f"{name} [shape={shape}];\n")
-                for name, (type, outputs) in self._modules.items():
-                    for output in outputs:
-                        fp.write(f"{name} -> {output};\n")
-                fp.write("}\n")
+        if self.files:
+            contents = "digraph G {\n"
+            contents += "rx [shape=circle, color=red, style=filled];\n"
+            for name, (type, outputs) in self._modules.items():
+                if type == "conjunction":
+                    shape = "diamond"
+                elif type == "flip-flop":
+                    shape = "box"
+                else:
+                    shape = "circle"
+                contents += f"{name} [shape={shape}];\n"
+            for name, (type, outputs) in self._modules.items():
+                for output in outputs:
+                    contents += f"{name} -> {output};\n"
+            contents += "}\n"
+
+            self.files.create("day20.dot", contents.encode(), False)
 
         # part 1
         flip_flop_states: dict[str, Literal["on", "off"]] = {
diff --git a/src/holt59/aoc/2023/day21.py b/src/holt59/aoc/2023/day21.py
index a525751..f5c3057 100644
--- a/src/holt59/aoc/2023/day21.py
+++ b/src/holt59/aoc/2023/day21.py
@@ -50,7 +50,7 @@ class Solver(BaseSolver):
         values.append(len(tiles := reachable(map, tiles, cycle)))
         values.append(len(tiles := reachable(map, tiles, cycle)))
 
-        if self.verbose:
+        if self.files:
             n_rows, n_cols = len(map), len(map[0])
 
             rows = [
@@ -66,8 +66,9 @@ class Solver(BaseSolver):
                     if (i // cycle) % 2 == (j // cycle) % 2:
                         rows[i][j] = f"\033[91m{rows[i][j]}\033[0m"
 
-            for row in rows:
-                self.logger.info("".join(row))
+            self.files.create(
+                "cycle.txt", "\n".join("".join(row) for row in rows).encode(), True
+            )
 
         self.logger.info(f"values to fit: {values}")
 
diff --git a/src/holt59/aoc/__main__.py b/src/holt59/aoc/__main__.py
index ff045e9..fff1ada 100644
--- a/src/holt59/aoc/__main__.py
+++ b/src/holt59/aoc/__main__.py
@@ -1,107 +1,15 @@
 import argparse
 import importlib
-import json
 import logging
 import logging.handlers
 import sys
-from datetime import datetime, timedelta
+from datetime import datetime
 from pathlib import Path
-from typing import Any, Iterable, Iterator, Literal, Sequence, TextIO, TypeVar
-
-from tqdm import tqdm
 
 from .base import BaseSolver
-
-_T = TypeVar("_T")
-
-
-def dump_api_message(
-    type: Literal["log", "answer", "progress-start", "progress-step", "progress-end"],
-    content: Any,
-    file: TextIO = sys.stdout,
-):
-    print(
-        json.dumps(
-            {"type": type, "time": datetime.now().isoformat(), "content": content}
-        ),
-        flush=True,
-        file=file,
-    )
-
-
-class LoggerAPIHandler(logging.Handler):
-    def __init__(self, output: TextIO = sys.stdout):
-        super().__init__()
-        self.output = output
-
-    def emit(self, record: logging.LogRecord):
-        dump_api_message(
-            "log", {"level": record.levelname, "message": record.getMessage()}
-        )
-
-
-class ProgressAPI:
-    def __init__(
-        self,
-        min_step: int = 1,
-        min_time: timedelta = timedelta(milliseconds=100),
-        output: TextIO = sys.stdout,
-    ):
-        super().__init__()
-
-        self.counter = 0
-        self.output = output
-        self.min_step = min_step
-        self.min_time = min_time
-
-    def wrap(
-        self, values: Sequence[_T] | Iterable[_T], total: int | None = None
-    ) -> Iterator[_T]:
-        total = total or len(values)  # type: ignore
-
-        current = self.counter
-        self.counter += 1
-
-        dump_api_message("progress-start", {"counter": current, "total": total})
-
-        try:
-            percent = 0
-            time = datetime.now()
-
-            for i_value, value in enumerate(values):
-                yield value
-
-                if datetime.now() - time < self.min_time:
-                    continue
-
-                time = datetime.now()
-
-                c_percent = round(i_value / total * 100)
-
-                if c_percent >= percent + self.min_step:
-                    dump_api_message(
-                        "progress-step", {"counter": current, "percent": c_percent}
-                    )
-                    percent = c_percent
-        finally:
-            dump_api_message(
-                "progress-end",
-                {"counter": current},
-            )
-
-
-class ProgressTQDM:
-    def wrap(
-        self, values: Sequence[_T] | Iterable[_T], total: int | None = None
-    ) -> Iterator[_T]:
-        return iter(tqdm(values, total=total))
-
-
-class ProgressNone:
-    def wrap(
-        self, values: Sequence[_T] | Iterable[_T], total: int | None = None
-    ) -> Iterator[_T]:
-        return iter(values)
+from .utils.api import FileHandlerAPI, LoggerAPIHandler, ProgressAPI, dump_answer
+from .utils.files import SimpleFileHandler
+from .utils.progress import ProgressNone, ProgressTQDM
 
 
 def main():
@@ -109,6 +17,13 @@ def main():
     parser.add_argument("-v", "--verbose", action="store_true", help="verbose mode")
     parser.add_argument("-t", "--test", action="store_true", help="test mode")
     parser.add_argument("-a", "--api", action="store_true", help="API mode")
+    parser.add_argument(
+        "-o",
+        "--output",
+        type=Path,
+        default=Path("files"),
+        help="output folder for created files",
+    )
     parser.add_argument(
         "-u", "--user", type=str, default="holt59", help="user input to use"
     )
@@ -135,12 +50,12 @@ def main():
     test: bool = args.test
     stdin: bool = args.stdin
     user: str = args.user
+    files_output: Path = args.output
     input_path: Path | None = args.input
 
     year: int = args.year
     day: int = args.day
 
-    # TODO: change this
     logging.basicConfig(
         level=logging.INFO if verbose or api else logging.WARNING,
         handlers=[LoggerAPIHandler()] if api else None,
@@ -166,7 +81,11 @@ def main():
         else ProgressTQDM()
         if verbose
         else ProgressNone(),  # type: ignore
-        outputs=not api,
+        files=FileHandlerAPI(files_output)
+        if api
+        else SimpleFileHandler(logging.getLogger("AOC"), files_output)
+        if verbose
+        else None,
     )
 
     data: str
@@ -189,14 +108,11 @@ def main():
         current = datetime.now()
 
         if api:
-            dump_api_message(
-                "answer",
-                {
-                    "answer": i_answer + 1,
-                    "value": str(answer),
-                    "answerTime_s": (current - last).total_seconds(),
-                    "totalTime_s": (current - start).total_seconds(),
-                },
+            dump_answer(
+                part=i_answer + 1,
+                answer=answer,
+                answer_time=current - last,
+                total_time=current - start,
             )
         else:
             print(
diff --git a/src/holt59/aoc/base.py b/src/holt59/aoc/base.py
index 5ba8ada..50cbaca 100644
--- a/src/holt59/aoc/base.py
+++ b/src/holt59/aoc/base.py
@@ -13,6 +13,10 @@ class ProgressHandler(Protocol):
     def wrap(self, values: Iterable[_T], total: int) -> Iterator[_T]: ...
 
 
+class FileHandler(Protocol):
+    def create(self, filename: str, content: bytes, text: bool = False): ...
+
+
 class BaseSolver:
     def __init__(
         self,
@@ -21,14 +25,14 @@ class BaseSolver:
         year: int,
         day: int,
         progress: ProgressHandler,
-        outputs: bool = False,
+        files: FileHandler | None = None,
     ):
         self.logger: Final = logger
         self.verbose: Final = verbose
         self.year: Final = year
         self.day: Final = day
         self.progress: Final = progress
-        self.outputs = outputs
+        self.files: Final = files
 
     @abstractmethod
     def solve(self, input: str) -> Iterator[Any] | None: ...
diff --git a/src/holt59/aoc/utils/__init__.py b/src/holt59/aoc/utils/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/src/holt59/aoc/utils/api/__init__.py b/src/holt59/aoc/utils/api/__init__.py
new file mode 100644
index 0000000..c9aa51b
--- /dev/null
+++ b/src/holt59/aoc/utils/api/__init__.py
@@ -0,0 +1,13 @@
+from .answer import dump_answer
+from .base import dump_api_message
+from .files import FileHandlerAPI
+from .logger import LoggerAPIHandler
+from .progress import ProgressAPI
+
+__all__ = [
+    "dump_answer",
+    "dump_api_message",
+    "FileHandlerAPI",
+    "LoggerAPIHandler",
+    "ProgressAPI",
+]
diff --git a/src/holt59/aoc/utils/api/answer.py b/src/holt59/aoc/utils/api/answer.py
new file mode 100644
index 0000000..42c2b33
--- /dev/null
+++ b/src/holt59/aoc/utils/api/answer.py
@@ -0,0 +1,16 @@
+from datetime import timedelta
+from typing import Any
+
+from .base import dump_api_message
+
+
+def dump_answer(part: int, answer: Any, answer_time: timedelta, total_time: timedelta):
+    dump_api_message(
+        "answer",
+        {
+            "answer": part,
+            "value": str(answer),
+            "answerTime_s": answer_time.total_seconds(),
+            "totalTime_s": total_time.total_seconds(),
+        },
+    )
diff --git a/src/holt59/aoc/utils/api/base.py b/src/holt59/aoc/utils/api/base.py
new file mode 100644
index 0000000..578dd70
--- /dev/null
+++ b/src/holt59/aoc/utils/api/base.py
@@ -0,0 +1,28 @@
+import json
+import sys
+from datetime import datetime
+from typing import Any, Literal, TextIO
+
+
+def _datetime_formatter(value: Any) -> Any:
+    if isinstance(value, datetime):
+        return value.isoformat()
+    else:
+        return value
+
+
+def dump_api_message(
+    type: Literal[
+        "log", "answer", "file", "progress-start", "progress-step", "progress-end"
+    ],
+    content: Any,
+    file: TextIO = sys.stdout,
+):
+    print(
+        json.dumps(
+            {"type": type, "time": datetime.now(), "content": content},
+            default=_datetime_formatter,
+        ),
+        flush=True,
+        file=file,
+    )
diff --git a/src/holt59/aoc/utils/api/files.py b/src/holt59/aoc/utils/api/files.py
new file mode 100644
index 0000000..d09d6ad
--- /dev/null
+++ b/src/holt59/aoc/utils/api/files.py
@@ -0,0 +1,15 @@
+from pathlib import Path
+from typing import Final
+
+from .base import dump_api_message
+
+
+class FileHandlerAPI:
+    def __init__(self, folder: Path):
+        self.folder: Final = folder
+
+    def create(self, filename: str, content: bytes, text: bool = False):
+        self.folder.mkdir(exist_ok=True)
+        with open(self.folder.joinpath(filename), "wb") as fp:
+            fp.write(content)
+        dump_api_message("file", {"filename": filename, "size": len(content)})
diff --git a/src/holt59/aoc/utils/api/logger.py b/src/holt59/aoc/utils/api/logger.py
new file mode 100644
index 0000000..6659b52
--- /dev/null
+++ b/src/holt59/aoc/utils/api/logger.py
@@ -0,0 +1,16 @@
+import logging.handlers
+import sys
+from typing import TextIO
+
+from .base import dump_api_message
+
+
+class LoggerAPIHandler(logging.Handler):
+    def __init__(self, output: TextIO = sys.stdout):
+        super().__init__()
+        self.output = output
+
+    def emit(self, record: logging.LogRecord):
+        dump_api_message(
+            "log", {"level": record.levelname, "message": record.getMessage()}
+        )
diff --git a/src/holt59/aoc/utils/api/progress.py b/src/holt59/aoc/utils/api/progress.py
new file mode 100644
index 0000000..837e95d
--- /dev/null
+++ b/src/holt59/aoc/utils/api/progress.py
@@ -0,0 +1,57 @@
+import sys
+from datetime import datetime, timedelta
+from typing import Iterable, Iterator, Sequence, TextIO, TypeVar
+
+from .base import dump_api_message
+
+_T = TypeVar("_T")
+
+
+class ProgressAPI:
+    def __init__(
+        self,
+        min_step: int = 1,
+        min_time: timedelta = timedelta(milliseconds=100),
+        output: TextIO = sys.stdout,
+    ):
+        super().__init__()
+
+        self.counter = 0
+        self.output = output
+        self.min_step = min_step
+        self.min_time = min_time
+
+    def wrap(
+        self, values: Sequence[_T] | Iterable[_T], total: int | None = None
+    ) -> Iterator[_T]:
+        total = total or len(values)  # type: ignore
+
+        current = self.counter
+        self.counter += 1
+
+        dump_api_message("progress-start", {"counter": current, "total": total})
+
+        try:
+            percent = 0
+            time = datetime.now()
+
+            for i_value, value in enumerate(values):
+                yield value
+
+                if datetime.now() - time < self.min_time:
+                    continue
+
+                time = datetime.now()
+
+                c_percent = round(i_value / total * 100)
+
+                if c_percent >= percent + self.min_step:
+                    dump_api_message(
+                        "progress-step", {"counter": current, "percent": c_percent}
+                    )
+                    percent = c_percent
+        finally:
+            dump_api_message(
+                "progress-end",
+                {"counter": current},
+            )
diff --git a/src/holt59/aoc/utils/files.py b/src/holt59/aoc/utils/files.py
new file mode 100644
index 0000000..91c71ff
--- /dev/null
+++ b/src/holt59/aoc/utils/files.py
@@ -0,0 +1,18 @@
+import logging
+from pathlib import Path
+from typing import Final
+
+
+class SimpleFileHandler:
+    def __init__(self, logger: logging.Logger, folder: Path):
+        self.logger: Final = logger
+        self.folder: Final = folder
+
+    def create(self, filename: str, content: bytes, text: bool = False):
+        if text:
+            for line in content.decode("utf-8").splitlines():
+                self.logger.info(line)
+        else:
+            self.folder.mkdir(exist_ok=True)
+            with open(self.folder.joinpath(filename), "wb") as fp:
+                fp.write(content)
diff --git a/src/holt59/aoc/utils/progress.py b/src/holt59/aoc/utils/progress.py
new file mode 100644
index 0000000..a26fabb
--- /dev/null
+++ b/src/holt59/aoc/utils/progress.py
@@ -0,0 +1,19 @@
+from typing import Iterable, Iterator, Sequence, TypeVar
+
+_T = TypeVar("_T")
+
+
+class ProgressTQDM:
+    def wrap(
+        self, values: Sequence[_T] | Iterable[_T], total: int | None = None
+    ) -> Iterator[_T]:
+        from tqdm import tqdm
+
+        return iter(tqdm(values, total=total))
+
+
+class ProgressNone:
+    def wrap(
+        self, values: Sequence[_T] | Iterable[_T], total: int | None = None
+    ) -> Iterator[_T]:
+        return iter(values)