diff --git a/src/server.test.ts b/src/server.test.ts
index f296319..ca64c93 100644
--- a/src/server.test.ts
+++ b/src/server.test.ts
@@ -40,11 +40,14 @@ test('Reads and writes from the file system', async () => {
   }
 
   // Store #1: Edge access
+  const server1Ops: string[] = []
   const directory1 = await tmp.dir()
   const server1 = new BlobsServer({
     directory: directory1.path,
+    onRequest: ({ type }) => server1Ops.push(type),
     token,
   })
+
   const { port: port1 } = await server1.start()
   const store1 = getStore({
     edgeURL: `http://localhost:${port1}`,
@@ -110,6 +113,28 @@ test('Reads and writes from the file system', async () => {
     expect(list3.directories).toEqual([])
   }
 
+  expect(server1Ops).toEqual([
+    'list',
+    'set',
+    'get',
+    'set',
+    'get',
+    'list',
+    'set',
+    'get',
+    'get',
+    'get',
+    'getMetadata',
+    'getMetadata',
+    'get',
+    'getMetadata',
+    'delete',
+    'get',
+    'getMetadata',
+    'get',
+    'list',
+  ])
+
   await server1.stop()
   await fs.rm(directory1.path, { force: true, recursive: true })
 
diff --git a/src/server.ts b/src/server.ts
index fa13b7b..bc366fe 100644
--- a/src/server.ts
+++ b/src/server.ts
@@ -6,11 +6,20 @@ import { dirname, join, relative, resolve, sep } from 'node:path'
 
 import { ListResponse } from './backend/list.ts'
 import { decodeMetadata, encodeMetadata, METADATA_HEADER_INTERNAL } from './metadata.ts'
+import { HTTPMethod } from './types.ts'
 import { isNodeError, Logger } from './util.ts'
 
 const API_URL_PATH = /\/api\/v1\/sites\/(?<site_id>[^/]+)\/blobs\/?(?<key>[^?]*)/
 const DEFAULT_STORE = 'production'
 
+export enum Operation {
+  DELETE = 'delete',
+  GET = 'get',
+  GET_METADATA = 'getMetadata',
+  LIST = 'list',
+  SET = 'set',
+}
+
 interface BlobsServerOptions {
   /**
    * Whether debug-level information should be logged, such as internal errors
@@ -28,6 +37,11 @@ interface BlobsServerOptions {
    */
   logger?: Logger
 
+  /**
+   * Callback function to be called on every request.
+   */
+  onRequest?: (parameters: { type: Operation }) => void
+
   /**
    * Port to run the server on. Defaults to a random port.
    */
@@ -45,16 +59,22 @@ export class BlobsServer {
   private debug: boolean
   private directory: string
   private logger: Logger
+  private onRequest: (parameters: { type: Operation }) => void
   private port: number
   private server?: http.Server
   private token?: string
   private tokenHash: string
 
-  constructor({ debug, directory, logger, port, token }: BlobsServerOptions) {
+  constructor({ debug, directory, logger, onRequest, port, token }: BlobsServerOptions) {
     this.address = ''
     this.debug = debug === true
     this.directory = directory
     this.logger = logger ?? console.log
+    this.onRequest =
+      onRequest ??
+      (() => {
+        // no-op
+      })
     this.port = port || 0
     this.token = token
     this.tokenHash = createHmac('sha256', Math.random.toString())
@@ -124,6 +144,8 @@ export class BlobsServer {
       return this.list({ dataPath, metadataPath, rootPath, req, res, url })
     }
 
+    this.onRequest({ type: Operation.GET })
+
     const headers: Record<string, string> = {}
 
     try {
@@ -193,6 +215,8 @@ export class BlobsServer {
     res: http.ServerResponse
     url: URL
   }) {
+    this.onRequest({ type: Operation.LIST })
+
     const { dataPath, rootPath, req, res, url } = options
     const directories = url.searchParams.get('directories') === 'true'
     const prefix = url.searchParams.get('prefix') ?? ''
@@ -295,17 +319,26 @@ export class BlobsServer {
       return this.sendResponse(req, res, 403)
     }
 
-    switch (req.method) {
-      case 'DELETE':
+    switch (req.method?.toLowerCase()) {
+      case HTTPMethod.DELETE: {
+        this.onRequest({ type: Operation.DELETE })
+
         return this.delete(req, res)
+      }
 
-      case 'GET':
+      case HTTPMethod.GET: {
         return this.get(req, res)
+      }
+
+      case HTTPMethod.PUT: {
+        this.onRequest({ type: Operation.SET })
 
-      case 'PUT':
         return this.put(req, res)
+      }
+
+      case HTTPMethod.HEAD: {
+        this.onRequest({ type: Operation.GET_METADATA })
 
-      case 'HEAD': {
         return this.head(req, res)
       }