diff --git a/.gitignore b/.gitignore
index cf8b1ff..d2fe01d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,3 +3,4 @@ releases
 collerd.db
 !docker/collerd.json
 collerd.json
+node_modules
diff --git a/package-lock.json b/package-lock.json
new file mode 100644
index 0000000..4cf810c
--- /dev/null
+++ b/package-lock.json
@@ -0,0 +1,40 @@
+{
+  "name": "coller",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {
+    "": {
+      "dependencies": {
+        "bootstrap": "^5.3.8"
+      }
+    },
+    "node_modules/@popperjs/core": {
+      "version": "2.11.8",
+      "resolved": "https://registry.npmjs.org/@popperjs/core/-/core-2.11.8.tgz",
+      "integrity": "sha512-P1st0aksCrn9sGZhp8GMYwBnQsbvAWsZAX44oXNNvLHGqAOcoVxmjZiohstwQ7SqKnbR47akdNi+uleWD8+g6A==",
+      "peer": true,
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/popperjs"
+      }
+    },
+    "node_modules/bootstrap": {
+      "version": "5.3.8",
+      "resolved": "https://registry.npmjs.org/bootstrap/-/bootstrap-5.3.8.tgz",
+      "integrity": "sha512-HP1SZDqaLDPwsNiqRqi5NcP0SSXciX2s9E+RyqJIIqGo+vJeN5AJVM98CXmW/Wux0nQ5L7jeWUdplCEf0Ee+tg==",
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/twbs"
+        },
+        {
+          "type": "opencollective",
+          "url": "https://opencollective.com/bootstrap"
+        }
+      ],
+      "peerDependencies": {
+        "@popperjs/core": "^2.11.8"
+      }
+    }
+  }
+}
diff --git a/package.json b/package.json
new file mode 100644
index 0000000..719e5df
--- /dev/null
+++ b/package.json
@@ -0,0 +1,5 @@
+{
+  "dependencies": {
+    "bootstrap": "^5.3.8"
+  }
+}
diff --git a/src/cmd/collerd/README.md b/src/cmd/collerd/README.md
index d99a273..0b51d6a 100644
--- a/src/cmd/collerd/README.md
+++ b/src/cmd/collerd/README.md
@@ -34,6 +34,7 @@ The file format is **JSON**:
 * **languages** ([]string): List of supported [languages](https://github.com/microsoft/monaco-editor/tree/main/src/basic-languages)
 * **language** (string): Default language (default "text")
 * **enable_upload_file_button** (bool): Display the upload file button in the UI (default true)
+* **bootstrap_directory** (string): Serve [Bootstrap](https://getbootstrap.com/) assets from this local directory (ex: "./node_modules/bootstrap/dist"). See **Dependencies** for details.
 
 The configuration file is not required but the service might not be exposed to the public.
 
@@ -76,4 +77,27 @@ If the note is encrypted, the encrypted value is returned (application/octet-str
 
 Errors return **500 Server Internal Error** with the **JSON** payload:
 * **message** (string): context of the error
-* **error** (string): error message
\ No newline at end of file
+* **error** (string): error message
+
+## Dependencies
+
+The web interface depends on:
+
+- [Bootstrap](https://getbootstrap.com/)
+- [Monaco Editor]https://github.com/microsoft/monaco-editor/)
+
+By default, those dependencies are fetched from **remote CDN** services by the client.
+
+If you would like to download them to serve them locally:
+
+```
+npm install
+```
+
+Then configure the local directories:
+
+```json
+{
+  "bootstrap_directory": "./node_modules/bootstrap/dist"
+}
+```
\ No newline at end of file
diff --git a/src/server/config.go b/src/server/config.go
index 8ba51ca..e1ef5e7 100644
--- a/src/server/config.go
+++ b/src/server/config.go
@@ -26,6 +26,7 @@ type Config struct {
 	Languages              []string `json:"languages"`
 	Language               string   `json:"language"`
 	EnableUploadFileButton bool     `json:"enable_upload_file_button"`
+	BootstrapDirectory     string   `json:"bootstrap_directory"`
 }
 
 func NewConfig() *Config {
diff --git a/src/server/server.go b/src/server/server.go
index 703714d..ab61605 100644
--- a/src/server/server.go
+++ b/src/server/server.go
@@ -195,6 +195,7 @@ type PageData struct {
 	URL                    string
 	Note                   *Note
 	EnableUploadFileButton bool
+	BootstrapDirectory     string
 }
 
 type HomeHandler struct {
@@ -429,10 +430,11 @@ func (s *Server) Start() error {
 		"string":        func(b []byte) string { return string(b) },
 	}
 	p := PageData{
-		Title:       s.config.Title,
-		Expirations: s.config.Expirations,
-		Expiration:  s.config.Expiration,
-		Languages:   s.config.Languages,
+		Title:              s.config.Title,
+		Expirations:        s.config.Expirations,
+		Expiration:         s.config.Expiration,
+		Languages:          s.config.Languages,
+		BootstrapDirectory: s.config.BootstrapDirectory,
 	}
 
 	if s.config.ShowVersion {
@@ -469,6 +471,10 @@ func (s *Server) Start() error {
 	}
 	r.Path("/{id:[a-zA-Z0-9]+}.html").Handler(webNoteHandler).Methods("GET")
 
+	if s.config.BootstrapDirectory != "" {
+		r.PathPrefix("/static/bootstrap/").Handler(http.StripPrefix("/static/bootstrap/", http.FileServer(http.Dir(s.config.BootstrapDirectory))))
+	}
+
 	r.Path("/").Handler(&HomeHandler{Templates: templates, PageData: p}).Methods("GET")
 
 	addr := fmt.Sprintf("%s:%d", s.config.ListenAddress, s.config.ListenPort)
diff --git a/src/server/templates/head.html b/src/server/templates/head.html
index bd8edba..e5f3544 100644
--- a/src/server/templates/head.html
+++ b/src/server/templates/head.html
@@ -4,6 +4,6 @@
     <title>{{.Title}}</title>
     <meta charset="utf-8">
     <meta name="viewport" content="width=device-width, initial-scale=1">
-    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/css/bootstrap.min.css" rel="stylesheet">
+    <link href="{{if ne .BootstrapDirectory ``}}/static/bootstrap/css/bootstrap.min.css{{else}}https://cdn.jsdelivr.net/npm/bootstrap@5.3.8/dist/css/bootstrap.min.css{{end}}" rel="stylesheet">
 </head>
 {{end}}
\ No newline at end of file