diff --git a/app/__init__.py b/app/__init__.py
new file mode 100644
index 0000000..1d9e4bb
--- /dev/null
+++ b/app/__init__.py
@@ -0,0 +1,43 @@
+import asyncio
+from typing import Any, Literal, overload
+
+from app.components.base import Component
+from app.components.http import HTTPComponent as HTTPComponent
+from app.components.lifespan import LifespanComponent as LifespanComponent
+from app.types_ import AnyScope, PassthroughDecorator, Receive, Send
+
+
+class App:
+    components: list[Component[Any, Any]]
+
+    def __init__(self) -> None:
+        self.components = []
+
+    async def __call__(self, scope: AnyScope, receive: Receive[Any], send: Send) -> Any:
+        async with asyncio.TaskGroup() as tg:
+            for compo in self.components:
+                if await compo.condition(scope):
+                    _ = tg.create_task(compo.handle(scope, receive, send))
+
+    @overload
+    def use_component[T: Component[Any, Any]](self, component: T) -> T: ...
+
+    @overload
+    def use_component(
+        self, component: Literal[None] = ..., *args: Any, **kwds: Any
+    ) -> PassthroughDecorator[type[Component[Any, Any]]]: ...
+
+    def use_component(
+        self, component: Component[Any, Any] | None = None, *args: Any, **kwds: Any
+    ) -> PassthroughDecorator[type[Component[Any, Any]]] | Component[Any, Any]:
+        if component is None:
+
+            def _use_component(
+                component: type[Component[Any, Any]], /
+            ) -> type[Component[Any, Any]]:
+                self.components.append(component(*args, **kwds))
+                return component
+
+            return _use_component
+        self.components.append(component)
+        return component
diff --git a/app/components/base.py b/app/components/base.py
new file mode 100644
index 0000000..cf5a892
--- /dev/null
+++ b/app/components/base.py
@@ -0,0 +1,35 @@
+from abc import ABCMeta, abstractmethod
+from collections.abc import MutableMapping
+from typing import Any, TypeGuard
+
+from app.types_ import AnyScope, AsyncCallable, Receive, Send
+
+
+class Component[S: AnyScope, R: Any](metaclass=ABCMeta):
+    def __init__(self, *args: Any, **kwds: Any) -> None:
+        pass
+
+    async def condition(self, scope: AnyScope) -> TypeGuard[S]:  # pyright: ignore[reportUnusedParameter]
+        """Determine whether the component should run."""
+        return True
+
+    @abstractmethod
+    async def handle(self, scope: S, receive: Receive[R], send: Send) -> None:
+        """Component processor."""
+        raise NotImplementedError
+
+
+class RouteComponent[S: AnyScope, Recv_T: Any, Route_T: MutableMapping[str, Any], Route_R: Any](Component[S, Recv_T], metaclass=ABCMeta):
+    routes: Route_T
+
+    def __init__(self, *args: Any, **kwds: Any) -> None:
+        super().__init__(*args, **kwds)
+
+    @abstractmethod
+    async def route_dispatch(self, scope: S, receive: Receive[Recv_T], send: Send) -> Any:
+        """Route dispatcher"""
+        raise NotImplementedError
+
+    def route_install(self, type_: str, route: str, target: AsyncCallable[..., Route_R]) -> None:
+        """Install route target for specific type and route."""
+        self.routes.setdefault(type_, {})[route] = target
\ No newline at end of file
diff --git a/app/components/http.py b/app/components/http.py
new file mode 100644
index 0000000..d307fed
--- /dev/null
+++ b/app/components/http.py
@@ -0,0 +1,99 @@
+from typing import TypeGuard, override
+
+from app.subroutines.http import Response, SimpleRequest, SimpleResponse
+from app.types_ import (
+    AnyScope,
+    AsyncCallable,
+    HTTPScope,
+    PassthroughDecorator,
+    Receive,
+    ReceiveHTTP,
+    RouteMapping,
+    Send,
+)
+
+from .base import RouteComponent as _RouteComponent
+
+
+class HTTPComponent(
+    _RouteComponent[HTTPScope, ReceiveHTTP, dict[str, RouteMapping[Response]], Response]
+):
+    routes: dict[str, RouteMapping[Response]]
+
+    def __init__(self) -> None:
+        self.routes = {}
+        super().__init__()
+
+    @override
+    async def condition(self, scope: AnyScope) -> TypeGuard[HTTPScope]:
+        return scope["type"] == "http"
+
+    @override
+    async def handle(
+        self, scope: HTTPScope, receive: Receive[ReceiveHTTP], send: Send
+    ) -> None:
+        req = SimpleRequest()
+        while not req.receive(await receive()):
+            pass
+
+        print(scope, req.body)
+        resp = await self.route_dispatch(scope, receive, send)
+        if resp is None:
+            resp = Response(status=404, body=b"404 Not Found\n")
+
+        async with SimpleResponse(send).prepare(
+            resp.status, headers=resp.headers
+        ) as rsp:
+            await rsp.finish(resp.body if resp.body is not None else b"")
+
+        return None
+
+    @override
+    async def route_dispatch(
+        self, scope: HTTPScope, receive: Receive[ReceiveHTTP], send: Send
+    ) -> Response | None:
+        for k, callee in self.routes[scope["method"].upper()].items():
+            if scope["path"] == k:  # temporary impl.
+                return await callee()
+
+    def route[T: AsyncCallable[..., Response]](
+        self,
+        route: str,
+        *,
+        get: bool = False,
+        post: bool = False,
+        put: bool = False,
+        delete: bool = False,
+    ) -> PassthroughDecorator[T]:
+        def __wrap_route(fn: T) -> T:
+            if get:
+                self.route_install("GET", route, fn)
+            if post:
+                self.route_install("POST", route, fn)
+            if put:
+                self.route_install("PUT", route, fn)
+            if delete:
+                self.route_install("DELETE", route, fn)
+            return fn
+
+        return __wrap_route
+
+    def get[T: AsyncCallable[..., Response]](
+        self, route: str
+    ) -> PassthroughDecorator[T]:
+        return self.route(route, get=True)
+
+    def post[T: AsyncCallable[..., Response]](
+        self, route: str
+    ) -> PassthroughDecorator[T]:
+        return self.route(route, post=True)
+
+    def put[T: AsyncCallable[..., Response]](
+        self, route: str
+    ) -> PassthroughDecorator[T]:
+        return self.route(route, put=True)
+
+    def delete[T: AsyncCallable[..., Response]](
+        self, route: str
+    ) -> PassthroughDecorator[T]:
+        return self.route(route, delete=True)
diff --git a/app/components/lifespan.py b/app/components/lifespan.py
new file mode 100644
index 0000000..efb9171
--- /dev/null
+++ b/app/components/lifespan.py
@@ -0,0 +1,25 @@
+from typing import TypeGuard, override
+
+from app.types_ import AnyScope, LifespanScope, Receive, ReceiveLifespan, Send
+
+from .base import Component as _Component
+
+
+class LifespanComponent(_Component[LifespanScope, ReceiveLifespan]):
+    @override
+    async def condition(self, scope: AnyScope) -> TypeGuard[LifespanScope]:
+        return scope["type"] == "lifespan"
+
+    @override
+    async def handle(self, scope: LifespanScope, receive: Receive[ReceiveLifespan], send: Send) -> None:
+        while True:
+            message = await receive()
+            if message['type'] == 'lifespan.startup':
+                ... # Do some startup here!
+                print("Startup...")
+                await send({'type': 'lifespan.startup.complete'})
+            elif message['type'] == 'lifespan.shutdown':
+                ... # Do some shutdown here!
+                print("Shutdown...")
+                await send({'type': 'lifespan.shutdown.complete'})
+                return
\ No newline at end of file
diff --git a/app/exceptions.py b/app/exceptions.py
new file mode 100644
index 0000000..39c676b
--- /dev/null
+++ b/app/exceptions.py
@@ -0,0 +1,10 @@
+class AppError(Exception):
+    pass
+
+
+class ConnectionClosed(AppError):
+    pass
+
+
+class ParseError(AppError):
+    pass
diff --git a/app/subroutines/_c_route.c b/app/subroutines/_c_route.c
new file mode 100644
index 0000000..ae929ac
--- /dev/null
+++ b/app/subroutines/_c_route.c
@@ -0,0 +1,152 @@
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+
+#define SEP 0x01
+#define FORMAT_START 0x03
+#define FORMAT_END 0x00
+#define DOUBLE_STAR 0x09
+
+void free_parsed_route(char *parsed) {
+    free(parsed);
+}
+
+// Helper function to write an Exact component to the output buffer
+static void write_exact(const char *value, size_t value_len, char **output, size_t *output_len) {
+    memcpy(*output, value, value_len);
+    *output += value_len;
+    **output = SEP;
+    (*output)++;
+    *output_len += value_len + 1;
+}
+
+// Helper function to write a Format component to the output buffer
+static void write_format(const char *name, size_t name_len, size_t minl, size_t maxl, int ignore_sep, char **output, size_t *output_len) {
+    // Write FORMAT_START marker
+    **output = FORMAT_START;
+    (*output)++;
+    *output_len += 1;
+
+    // Write the name
+    memcpy(*output, name, name_len);
+    *output += name_len;
+    **output = FORMAT_END;
+    (*output)++;
+    *output_len += name_len + 1;
+
+    // Write minl and maxl as size_t values
+    memcpy(*output, &minl, sizeof(size_t));
+    *output += sizeof(size_t);
+    memcpy(*output, &maxl, sizeof(size_t));
+    *output += sizeof(size_t);
+    *output_len += 2 * sizeof(size_t);
+
+    // Write ignore_sep as a single byte
+    **output = (char)ignore_sep;
+    (*output)++;
+    **output = SEP;
+    (*output)++;
+    *output_len += 2;
+}
+
+// Main parsing function
+char *parse_route(const char *route, size_t route_len, size_t *output_len) {
+    char *output = malloc(route_len * 8); // Allocate enough space for the output
+    if (!output) return NULL;
+    char *output_start = output;
+    *output_len = 0;
+
+    const char *p = route;
+    const char *end = route + route_len;
+
+    while (p < end) {
+        if (*p == '/') {
+            // Skip leading slashes
+            write_exact("/", 1, &output, output_len);
+            p++;
+            continue;
+        } else if (*p == '{') {
+            // Handle Format component
+            const char *start = p + 1; // Skip '{'
+            const char *end_brace = memchr(start, '}', end - start);
+            if (!end_brace) break; // Invalid format, stop parsing
+
+            // Extract name and constraints
+            const char *colon = memchr(start, ':', end_brace - start);
+            size_t name_len = colon ? (size_t)(colon - start) : (size_t)(end_brace - start);
+            const char *name = start;
+            size_t minl = 0, maxl = (size_t)-1, ignore_sep = 0;
+
+            if (colon) {
+                const char *constraint = colon + 1;
+                if (memchr(constraint, '-', end_brace - constraint)) {
+                    // Parse "minl-maxl"
+                    sscanf(constraint, "%zu-%zu", &minl, &maxl);
+                } else {
+                    // Parse "minl" (fixed length)
+                    sscanf(constraint, "%zu", &minl);
+                    maxl = minl;
+                }
+            }
+
+            // Write the Format component
+            write_format(name, name_len, minl, maxl, ignore_sep, &output, output_len);
+
+            p = end_brace + 1; // Move past '}'
+        } else if (*p == '*' && *(p + 1) == '*') {
+            // Handle "**" as a special marker (\x09)
+            *output = DOUBLE_STAR;
+            output++;
+            *output = SEP;
+            output++;
+            *output_len += 2;
+            p += 2; // Move past "**"
+        } else {
+            // Handle Exact component
+            const char *next_slash = memchr(p, '/', end - p);
+            size_t segment_len = next_slash ? (size_t)(next_slash - p) : (size_t)(end - p);
+            write_exact(p, segment_len, &output, output_len);
+            p += segment_len;
+        }
+    }
+
+    // Null-terminate the output
+    *output = '\0';
+    *output_len += 1;
+
+    return output_start;
+}
+
+// // Example usage
+// int main() {
+//     const char *route = "/foo/{n:5}/bar/**/baz";
+//     size_t route_len = strlen(route);
+//     size_t output_len;
+
+//     char *result = parse_route(route, route_len, &output_len);
+//     if (!result) {
+//         fprintf(stderr, "Memory allocation failed\n");
+//         return 1;
+//     }
+
+//     printf("Parsed result (%zu bytes):\n", output_len);
+//     for (size_t i = 0; i < output_len; i++) {
+//         if (result[i] == SEP) {
+//             printf("\\x01");
+//         } else if (result[i] == FORMAT_START) {
+//             printf("\\x03");
+//         } else if (result[i] == FORMAT_END) {
+//             printf("\\x00");
+//         } else if (result[i] == DOUBLE_STAR) {
+//             printf("\\x09");
+//         } else {
+//             printf("%c", result[i]);
+//         }
+//     }
+//     printf("\n");
+
+//     free(result);
+//     return 0;
+// }
diff --git a/app/subroutines/http.py b/app/subroutines/http.py
new file mode 100644
index 0000000..86a2c50
--- /dev/null
+++ b/app/subroutines/http.py
@@ -0,0 +1,138 @@
+from collections.abc import MutableMapping
+from dataclasses import InitVar, dataclass, field
+from http.cookies import BaseCookie
+from types import TracebackType
+from typing import Any, Self
+
+from app.exceptions import ConnectionClosed
+from app.types_ import CommonMapping, ReceiveHTTP, Send
+
+
+class SimpleRequest:
+    body: bytes
+    body_parts: list[bytes]
+    body_complete: bool
+    done: bool
+    keep_unset_body: bool = False
+
+    def __init__(self, keep_unset_body: bool | None = None) -> None:
+        self.body = b""
+        self.body_parts = []
+        self.body_complete = False
+        self.done = False
+        if keep_unset_body is not None:
+            self.keep_unset_body = keep_unset_body
+
+    def receive(self, received: ReceiveHTTP) -> bool:
+        if received["type"] == "http.disconnect":
+            self.done = True
+            return True
+            
+        if "body" in received:
+            self.body_parts.append(received["body"])
+        elif self.keep_unset_body:
+            self.body_parts.append(b"")
+
+        if not ("more_body" in received and received["more_body"]):
+            self.body = b"".join(self.body_parts)
+            self.body_complete = True
+
+        return self.body_complete or self.done
+
+
+class SimpleResponse:
+    send: Send
+    headers: list[tuple[bytes, bytes]]
+    status: int
+    trailers: bool
+    done: bool
+
+    def __init__(self, send: Send) -> None:
+        self.send = send
+        self.headers = []
+        self.status = 200
+        self.trailers = False
+        self.done = False
+
+    def add_header(self, name: str, value: object) -> None:
+        self.headers.append((name.lower().encode(), str(value).encode()))
+
+    def prepare(self, status: int = 200, trailers: bool = False, headers: MutableMapping[str, str] | None = None) -> Self:
+        self.status = status
+        self.trailers = trailers
+        if headers:
+            for k, v in headers.items():
+                self.add_header(k, v)
+        return self
+
+    async def start(self) -> None:
+        if self.done:
+            raise ConnectionClosed
+        await self.send({
+            "type": "http.response.start",
+            "status": self.status,
+            "headers": self.headers,
+            "trailers": self.trailers
+        })
+
+    async def body(self, data: bytes = b"", *, done: bool = True) -> None:
+        if self.done:
+            raise ConnectionClosed
+        await self.send({
+            "type": "http.response.body",
+            "body": data,
+            "more_body": not done
+        })
+        self.done = done and not self.trailers
+
+    async def part(self, data: bytes = b"") -> None:
+        """Same as `Response.body(data, done=False)`"""
+        return await self.body(data, done=False)
+
+    async def finish(self, data: bytes = b"") -> None:
+        """Same as `Response.body(data, done=True)`"""
+        return await self.body(data, done=True)
+
+    async def trail(self) -> None:
+        if self.done:
+            raise ConnectionClosed
+        await self.send({"type": "http.response.trailers"})
+        self.done = True
+
+    async def __aenter__(self) -> Self:
+        await self.start()
+        return self
+
+    async def __aexit__(self, exc_type: type[BaseException] | None, exc_value: BaseException | None, traceback: TracebackType | None, /) -> bool | None:
+        if not (self.done or exc_type):
+            await self.finish()
+        if exc_type and self.trailers:
+            await self.trail()
+        return None
+
+
+@dataclass
+class Response:
+    status: int = 200
+    body: bytes | None = None
+    headers: CommonMapping = field(default_factory=dict[str, Any])
+    content_type: InitVar[str | None] = None
+    cookies: InitVar[BaseCookie[bytes] | None] = None
+
+    def __post_init__(self, content_type: str | None, cookies: BaseCookie[bytes] | None) -> None:
+        if self.body is not None:
+            self.headers["content-length"] = len(self.body)
+        if content_type is not None:
+            self.headers["content-type"] = content_type
+        if cookies is not None:
+            self.headers["set-cookie"] = cookies.output(header="").strip()
+
+
+@dataclass
+class HTMLResponse(Response):
+    content: InitVar[str] = ""
+    encoding: InitVar[str] = "utf-8"
+
+    def __post_init__(self, content_type: str | None, cookies: BaseCookie[bytes] | None, content: str, encoding: str) -> None:
+        self.body: bytes | None = content.encode(encoding)
+        return super().__post_init__("text/html", cookies)
diff --git a/app/subroutines/route.py b/app/subroutines/route.py
new file mode 100644
index 0000000..cbd6456
--- /dev/null
+++ b/app/subroutines/route.py
@@ -0,0 +1,48 @@
+# /                 -> Exact("/")
+# /foo              -> Exact("/foo")
+# /foo/             -> Exact("/foo/")
+# /foo/bar          -> Exact("/foo/bar")
+# /foo/bar/{n}      -> Exact("/foo/bar/"), Format("n")
+# /foo/{n}/bar      -> Exact("/foo/"), Format("n"), Exact("/bar")
+# /foo{n:5}/bar     -> Exact("/foo"), Format("n", minl=5, maxl=5), Exact("/bar")
+# /foo/{m:1-}/{n:3-5}bar -> Exact("/foo/"), Format("m", minl=1, maxl=-1), Exact("/"), Format("n", minl=3, maxl=5), Exact("bar")
+# /*                -> Exact("/"), Format("_")
+# /foo/*bar         -> Exact("/foo/"), Format("_"), Exact("bar")
+# /foo/*/bar        -> Exact("/foo/"), Format("_"), Exact("/bar")
+# /foo/**/bar       -> Exact("/foo/"), Format("_", ignore_sep=True), Exact("/bar")
+
+# ["foo", Format("m", minl=1, maxl=-1), [Format("n", minl=3, maxl=5), "bar"], "*"]
+
+
+import ctypes
+
+dll = ctypes.CDLL("./c_route.so")
+dll.parse_route.restype = type("c_char_alloc", (ctypes.c_char_p,), {})
+dll.free_parsed_route.argtypes = (ctypes.c_void_p,)
+dll.free_parsed_route.restype = None
+
+
+def compile_route(pattern: str) -> list[bytes]:
+    if pattern[0] != "/":
+        from app.exceptions import ParseError
+        raise ParseError("The first character in route pattern must be '/'.")
+
+    # res: list[str] = []
+    # for path in pattern[1:].split("/"):
+    #     if (star_idx := path.find("*")) != -1:
+    #         path = "".join((path[:star_idx], "{_}", path[star_idx + 1:]))
+    #     if "{" not in path and "}" not in path and "*" not in path:
+    #         res.append(path)
+
+    outlen = ctypes.c_size_t()
+    data = pattern[1:].encode()
+    ret = dll.parse_route(data, len(data), ctypes.byref(outlen))
+    res = ctypes.string_at(ret, outlen.value - 2).split(b"\x01")
+    dll.free_parsed_route(ret)
+
+    return res
+
+
+if __name__ == "__main__":
+    print(compile_route("/foo/{n:5}foo/bar/**/baz"))
+    print(compile_route("/"))
diff --git a/app/types_.py b/app/types_.py
new file mode 100644
index 0000000..c96cc11
--- /dev/null
+++ b/app/types_.py
@@ -0,0 +1,69 @@
+from collections.abc import (
+    Awaitable,
+    Coroutine,
+    Mapping,
+    MutableMapping,
+    MutableSequence,
+)
+from typing import Any, Callable, Literal, NotRequired, TypedDict
+
+type CommonMapping = MutableMapping[str, Any]
+
+type PassthroughDecorator[F: Callable[..., Any]] = Callable[[F], F]
+type WrappingDecorator[**P, R] = Callable[[Callable[P, R]], Callable[P, R]]
+
+type HostPortTuple = tuple[str, int]
+type UnixSocketTuple = tuple[str, Literal[None]]
+type Receive[R: Mapping[str, Any]] = Callable[[], Coroutine[Any, Any, R]]
+type Send = Callable[[CommonMapping], Coroutine[Any, Any, None]]
+
+type AsyncCallable[**P, R] = Callable[P, Awaitable[R]]
+type AnyAsyncCallable = AsyncCallable[..., Any]
+type RouteMapping[R] = MutableMapping[str, AsyncCallable[..., R]]
+
+
+class ASGIInfo(TypedDict):
+    version: str
+    spec_version: str
+
+
+class LifespanScope(TypedDict):
+    type: Literal["lifespan"]
+    asgi: ASGIInfo
+    state: CommonMapping
+
+
+class HTTPScope(TypedDict):
+    type: Literal["http"]
+    asgi: ASGIInfo
+    http_version: str
+    server: HostPortTuple | UnixSocketTuple
+    client: HostPortTuple
+    scheme: str
+    method: Literal["GET", "HEAD", "POST", "PUT", "PATCH", "DELETE", "OPTIONS"]
+    root_path: str
+    path: str
+    raw_path: bytes
+    query_string: bytes
+    headers: MutableSequence[tuple[str, str]]
+    state: CommonMapping
+
+
+type AnyScope = LifespanScope | HTTPScope
+
+
+class ReceiveLifespan(TypedDict):
+    type: Literal["lifespan.startup", "lifespan.shutdown"]
+
+
+class ReceiveHTTPRequest(TypedDict):
+    type: Literal["http.request"]
+    body: NotRequired[bytes]
+    more_body: NotRequired[bool]
+
+
+class ReceiveHTTPDisconnect(TypedDict):
+    type: Literal["http.disconnect"]
+
+
+type ReceiveHTTP = ReceiveHTTPRequest | ReceiveHTTPDisconnect
diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 0000000..cce2d9d
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,4 @@
+[tool.basedpyright]
+typeCheckingMode = "recommended"
+reportAny = false
+reportExplicitAny = false
\ No newline at end of file
diff --git a/test.py b/test.py
new file mode 100644
index 0000000..7e0e126
--- /dev/null
+++ b/test.py
@@ -0,0 +1,27 @@
+from app import App
+from app.components.http import HTTPComponent
+
+# from app.components.lifespan import LifespanComponent
+from app.subroutines.http import HTMLResponse
+
+app = App()
+
+# lifespan = app.use_component(LifespanComponent())
+http = app.use_component(HTTPComponent())
+
+
+@http.route("/teapot", get=True, post=True, put=True, delete=True)
+async def teapot() -> HTMLResponse:
+    resp = """
+    <!DOCTYPE html>
+    <html>
+        <head>
+            <title>I'm a Teapot!!!</title>
+        </head>
+        <body>
+            <h1>I'm a Teapot!!!</h1>
+            <p>I've already told you I'm a teapot.</p>
+        </body>
+    </html>
+    """
+    return HTMLResponse(status=418, content=resp)