diff --git a/logging.common.js b/logging.common.js
index 5c897c2..969d930 100644
--- a/logging.common.js
+++ b/logging.common.js
@@ -16,17 +16,22 @@ export const UNCOLOR = symbol.create()
 
 /* c8 ignore start */
 /**
- * @param {Array<string|Symbol|Object|number>} args
+ * @param {Array<undefined|string|Symbol|Object|number|function():any>} args
  * @return {Array<string|object|number>}
  */
 export const computeNoColorLoggingArgs = args => {
+  if (args.length === 1 && args[0]?.constructor === Function) {
+    args = /** @type {Array<string|Symbol|Object|number>} */ (/** @type {[function]} */ (args)[0]())
+  }
   const strBuilder = []
   const logArgs = []
   // try with formatting until we find something unsupported
   let i = 0
   for (; i < args.length; i++) {
     const arg = args[i]
-    if (arg.constructor === String || arg.constructor === Number) {
+    if (arg === undefined) {
+      strBuilder.push('undefined')
+    } else if (arg.constructor === String || arg.constructor === Number) {
       strBuilder.push(arg)
     } else if (arg.constructor === Object) {
       logArgs.push(JSON.stringify(arg))
@@ -57,6 +62,9 @@ export const createModuleLogger = (_print, moduleName) => {
   return !doLogging
     ? func.nop
     : (...args) => {
+        if (args.length === 1 && args[0]?.constructor === Function) {
+          args = args[0]()
+        }
         const timeNow = time.getUnixTime()
         const timeDiff = timeNow - lastLoggingTime
         lastLoggingTime = timeNow
@@ -65,7 +73,7 @@ export const createModuleLogger = (_print, moduleName) => {
           moduleName,
           UNCOLOR,
           ...args.map((arg) => {
-            if (arg != null && arg.constructor !== Uint8Array) {
+            if (arg != null && arg.constructor === Uint8Array) {
               arg = Array.from(arg)
             }
             const t = typeof arg
diff --git a/logging.js b/logging.js
index feae871..d6c77c6 100644
--- a/logging.js
+++ b/logging.js
@@ -32,11 +32,14 @@ const _browserStyleMap = {
 }
 
 /**
- * @param {Array<string|Symbol|Object|number>} args
+ * @param {Array<string|Symbol|Object|number|function():any>} args
  * @return {Array<string|object|number>}
  */
 /* c8 ignore start */
 const computeBrowserLoggingArgs = (args) => {
+  if (args.length === 1 && args[0]?.constructor === Function) {
+    args = /** @type {Array<string|Symbol|Object|number>} */ (/** @type {[function]} */ (args)[0]())
+  }
   const strBuilder = []
   const styles = []
   const currentStyle = map.create()
@@ -53,6 +56,9 @@ const computeBrowserLoggingArgs = (args) => {
     if (style !== undefined) {
       currentStyle.set(style.left, style.right)
     } else {
+      if (arg === undefined) {
+        break
+      }
       if (arg.constructor === String || arg.constructor === Number) {
         const style = dom.mapToStyleString(currentStyle)
         if (i > 0 || style.length > 0) {
@@ -195,12 +201,15 @@ const _computeLineSpans = (args) => {
   // try with formatting until we find something unsupported
   let i = 0
   for (; i < args.length; i++) {
-    const arg = args[i]
+    let arg = args[i]
     // @ts-ignore
     const style = _browserStyleMap[arg]
     if (style !== undefined) {
       currentStyle.set(style.left, style.right)
     } else {
+      if (arg === undefined) {
+        arg = 'undefined '
+      }
       if (arg.constructor === String || arg.constructor === Number) {
         // @ts-ignore
         const span = dom.element('span', [
diff --git a/logging.node.js b/logging.node.js
index dc54c3d..63d41ec 100644
--- a/logging.node.js
+++ b/logging.node.js
@@ -23,10 +23,13 @@ const _nodeStyleMap = {
 
 /* c8 ignore start */
 /**
- * @param {Array<string|Symbol|Object|number>} args
- * @return {Array<string|object|number>}
+ * @param {Array<string|undefined|Symbol|Object|number|function():Array<any>>} args
+ * @return {Array<string|object|number|undefined>}
  */
 const computeNodeLoggingArgs = (args) => {
+  if (args.length === 1 && args[0]?.constructor === Function) {
+    args = /** @type {Array<string|Symbol|Object|number>} */ (/** @type {[function]} */ (args)[0]())
+  }
   const strBuilder = []
   const logArgs = []
   // try with formatting until we find something unsupported
@@ -38,7 +41,9 @@ const computeNodeLoggingArgs = (args) => {
     if (style !== undefined) {
       strBuilder.push(style)
     } else {
-      if (arg.constructor === String || arg.constructor === Number) {
+      if (arg === undefined) {
+        break
+      } else if (arg.constructor === String || arg.constructor === Number) {
         strBuilder.push(arg)
       } else {
         break
@@ -68,7 +73,7 @@ const computeLoggingArgs = env.supportsColor
 /* c8 ignore stop */
 
 /**
- * @param {Array<string|Symbol|Object|number>} args
+ * @param {Array<string|Symbol|Object|number|undefined>} args
  */
 export const print = (...args) => {
   console.log(...computeLoggingArgs(args))
diff --git a/logging.test.js b/logging.test.js
index c59b91a..eecfd4e 100644
--- a/logging.test.js
+++ b/logging.test.js
@@ -14,4 +14,15 @@ export const testLogging = () => {
   log.print(log.BLUE, log.BOLD, 'number', 1)
   log.print(log.BLUE, log.BOLD, 'number', 1, {}, 's', 2)
   log.print({}, 'dtrn')
+  log.print(() => [log.GREEN, 'can lazyprint stuff ', log.RED, 'with formatting'])
+  log.print(undefined, 'supports undefined')
+}
+
+export const testModuleLogger = () => {
+  // if you want to see the messages, enable logging: LOG=* npm run test --filter logging
+  const mlog = log.createModuleLogger('testing')
+  mlog('can print ', log.GREEN, 'with colors')
+  mlog(() => ['can lazyprint ', log.GREEN, 'with colors'])
+  mlog(undefined, 'supports undefined')
+  mlog(() => [undefined, 'supports lazyprint undefined'])
 }
diff --git a/test.html b/test.html
index 19ccb42..93e723b 100644
--- a/test.html
+++ b/test.html
@@ -29,6 +29,7 @@
   "lib0/conditions.js": "./conditions.js",
   "lib0/dist/conditions.cjs": "./dist/conditions.cjs",
   "lib0/conditions": "./condititons.js",
+  "lib0/crypto/jwt": "./crypto/jwt.js",
   "lib0/crypto/aes-gcm": "./crypto/aes-gcm.js",
   "lib0/crypto/ecdsa": "./crypto/ecdsa.js",
   "lib0/crypto/rsa-oaep": "./crypto/rsa-oaep.js",