diff --git a/src/scicloj/clay/v2/api.clj b/src/scicloj/clay/v2/api.clj
index e42617b7..dea6348d 100644
--- a/src/scicloj/clay/v2/api.clj
+++ b/src/scicloj/clay/v2/api.clj
@@ -1,12 +1,11 @@
 (ns scicloj.clay.v2.api
   (:require
-   [clojure.string :as string]
    [clojure.test]
    [scicloj.clay.v2.config :as config]
+   [scicloj.clay.v2.files :as files]
    [scicloj.clay.v2.live-reload :as live-reload]
    [scicloj.clay.v2.server :as server]
    [scicloj.clay.v2.make :as make]
-   [scicloj.kindly.v4.api :as kindly]
    [scicloj.kindly.v4.kind :as kind]))
 
 (defn stop! []
diff --git a/src/scicloj/clay/v2/files.clj b/src/scicloj/clay/v2/files.clj
index 3e53c8d8..1fb047cd 100644
--- a/src/scicloj/clay/v2/files.clj
+++ b/src/scicloj/clay/v2/files.clj
@@ -2,6 +2,9 @@
   (:require [clojure.java.io :as io]
             [babashka.fs :as fs]))
 
+;; will be bound when the notebook is being evaluated
+(def ^:dynamic *context* nil)
+
 (def *target-path->files (atom {}))
 
 (defn init-target! [target-path]
@@ -43,3 +46,15 @@
                              (get value))]
             (io/make-parents new-file)
             [new-file (relative-url target-path new-file)])))))
+
+(defn notebook-relative-file!
+  "When evaluated by Clay as a notebook,
+   returns a pair of [file relative-path] such that one can write to file,
+   and include it in a document using the relative path.
+   When evaluated outside of Clay, returns nil.
+   `custom-name` will be used as a filename prefix.
+   `value` is used for de-duplication, only one file is returned per value.
+   `ext` is the file extension."
+  [custom-name value ext]
+  (when *context*
+    (next-file! *context* custom-name value ext)))
diff --git a/src/scicloj/clay/v2/notebook.clj b/src/scicloj/clay/v2/notebook.clj
index 6d5f9e79..773422fb 100644
--- a/src/scicloj/clay/v2/notebook.clj
+++ b/src/scicloj/clay/v2/notebook.clj
@@ -1,6 +1,7 @@
 (ns scicloj.clay.v2.notebook
   (:require [clojure.string :as str]
             [clojure.pprint :as pp]
+            [scicloj.clay.v2.files :as files]
             [scicloj.clay.v2.util.path :as path]
             [scicloj.clay.v2.item :as item]
             [scicloj.clay.v2.prepare :as prepare]
@@ -430,7 +431,8 @@
   (binding [*ns* *ns*
             *warn-on-reflection* *warn-on-reflection*
             *unchecked-math* *unchecked-math*
-            pp/*print-right-margin* pprint-margin]
+            pp/*print-right-margin* pprint-margin
+            files/*context* spec]
     (-> (relevant-notes spec)
         (complete-notes spec)
         (with-out-err-captured))))