diff --git a/src/session.ts b/src/session.ts
index b28ae1f..4694fa0 100644
--- a/src/session.ts
+++ b/src/session.ts
@@ -16,9 +16,8 @@ export default function session<
   const name = options.name || "sid"
   const store = options.store || new MemoryStore()
   const genId = options.genid || nanoid
-  const encode = options.encode
   const touchAfter = options.touchAfter ?? -1
-  const cookieOpts = options.cookie || {}
+  const { unsign, ...cookieOpts } = options.cookie ?? {}
 
   function decorateSession(req: Req, res: Res, session: TypedSession, id: string, _now: number) {
     Object.defineProperties(session, {
@@ -53,8 +52,13 @@ export default function session<
 
     const _now = Date.now()
 
-    let sessionId = req.cookies[name]?.value
+    const sessionCookie = req.cookies[name]
+    if (unsign != null && sessionCookie != null && !sessionCookie.signed) sessionCookie.unsign(unsign)
 
+    let sessionId: string | null = null
+    try {
+      sessionId = sessionCookie?.value ?? null
+    } catch (err) {}
     const _session = sessionId ? await store.get(sessionId) : null
 
     let session: TypedSession
@@ -101,7 +105,7 @@ export default function session<
 
     res.registerLateHeaderAction(lateHeaderAction, (res: Res) => {
       if (!(session[isNew] && Object.keys(session).length > 1) && !session[isTouched] && !session[isDestroyed]) return
-      appendSessionCookieHeader(res, name, session, encode)
+      appendSessionCookieHeader(res, name, session, cookieOpts)
     })
 
     return session
diff --git a/src/types.ts b/src/types.ts
index cea675b..eaf1135 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -38,12 +38,33 @@ export interface SessionStore {
 }
 
 export interface Options {
-  name?: string
-  store?: SessionStore
-  genid?: () => string
-  encode?: (rawSid: string) => string
-  decode?: (encryptedSid: string) => string | null
-  touchAfter?: number
-  cookie?: Partial<Pick<Cookie, "maxAge" | "httpOnly" | "path" | "domain" | "secure" | "sameSite">>
-  autoCommit?: boolean
+  name?: string | undefined
+  store?: SessionStore | undefined
+  genid?: (() => string) | undefined
+  touchAfter?: number | undefined
+  cookie?:
+    | (Partial<Exclude<Cookie, "expires">> & {
+        /**
+         * `otterhttp` cookie `sign` function, will be passed to `res.cookie`.
+         * @default undefined
+         */
+        sign?: ((value: string) => string) | undefined
+
+        /**
+         * `otterhttp` cookie 'unsign' function, will be used to unsign session cookies.
+         *
+         * You must ensure that encoded session cookies are not matched by your `otterhttp` `App`'s configured
+         * `signedCookieMatcher`. Otherwise, `otterhttp` will attempt to decode session cookies using the `App`'s configured
+         * `cookieUnsigner` instead, and unsigning with this function will not be attempted.
+         * @default undefined
+         */
+        unsign?: ((signedValue: string) => string) | undefined
+
+        /**
+         * `otterhttp` cookie 'encode' function, will be passed to `res.cookie`.
+         * @default undefined
+         */
+        encode?: ((value: string) => string) | undefined
+      })
+    | undefined
 }
diff --git a/src/utils.ts b/src/utils.ts
index 7449f55..0349a72 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -2,14 +2,11 @@ import type { Request, Response } from "@otterhttp/app"
 
 import type { Options, Session } from "./types"
 
-export function appendSessionCookieHeader<
-  Req extends Request = Request,
-  Res extends Response<Req> = Response<Req>,
->(
+export function appendSessionCookieHeader<Req extends Request = Request, Res extends Response<Req> = Response<Req>>(
   res: Res,
   name: string,
   { cookie, id }: Pick<Session, "cookie" | "id">,
-  encodeFn?: Options["encode"],
+  { encode, sign }: Pick<Exclude<Options["cookie"], undefined>, "encode" | "sign">,
 ) {
   if (res.headersSent) return
   res.cookie(name, id, {
@@ -19,6 +16,7 @@ export function appendSessionCookieHeader<
     domain: cookie.domain,
     sameSite: cookie.sameSite,
     secure: cookie.secure,
-    encode: encodeFn,
+    encode,
+    sign,
   })
 }
diff --git a/test/session.test.ts b/test/session.test.ts
index 7d54805..68aa452 100644
--- a/test/session.test.ts
+++ b/test/session.test.ts
@@ -63,7 +63,10 @@ describe("session()", () => {
     const cookie = {
       httpOnly: false,
     }
-    const sess = await session({ cookie })({} as Request, { registerLateHeaderAction: vi.fn() } as unknown as Response)
+    const sess = await session({ cookie })(
+      { cookies: {} } as Request,
+      { registerLateHeaderAction: vi.fn() } as unknown as Response,
+    )
 
     expect(sess.cookie.httpOnly).toBeFalsy()
   })
@@ -282,16 +285,16 @@ describe("session()", () => {
         .end()
     })
   })
-  test("allow encode and decode sid", async () => {
-    const decode = (key: string) => {
+  test("allow sign and unsign sid", async () => {
+    const unsign = (key: string) => {
       if (key.startsWith("sig.")) return key.substring(4)
-      return null
+      throw new Error()
     }
-    const encode = (key: string) => {
+    const sign = (key: string) => {
       return `sig.${key}`
     }
     const store = new MemoryStore()
-    const sessionFn = session({ store, encode, decode })
+    const sessionFn = session({ store, cookie: { sign, unsign } })
     let sid: string | undefined
     const app = new App<Request, Response>()
     app.use("/", async (req: Request, res: Response, next) => {
@@ -317,10 +320,10 @@ describe("session()", () => {
 
     const res1 = await fetch("/first")
     expect(sid).toBeDefined()
-    expect(res1.headers.getSetCookie()).toContain(`sid=${encode(sid as string)}; Path=/; HttpOnly`)
+    expect(res1.headers.getSetCookie()).toContain(`sid=${sign(sid as string)}; Path=/; HttpOnly`)
     expect(store.store.has(sid as string)).toBe(true)
 
-    const res2 = await fetch("/second", { headers: { cookie: `sid=${encode(sid as string)}` } })
+    const res2 = await fetch("/second", { headers: { cookie: `sid=${sign(sid as string)}` } })
     await expect(res2.text()).resolves.toEqual("bar")
 
     const res3 = await fetch("/second", { headers: { cookie: `sid=${sid}` } })