diff --git a/components/api-server/src/application.js b/components/api-server/src/application.js
index a84612a14..062a86b17 100644
--- a/components/api-server/src/application.js
+++ b/components/api-server/src/application.js
@@ -56,6 +56,7 @@ const userLocalDirectory = require('business').users.userLocalDirectory;
 const { Extension, ExtensionLoader } = require('utils').extension;
 
 const { getAPIVersion } = require('middleware/src/project_version');
+const { pubsub } = require('messages');
 const { tracingMiddleware } = require('tracing');
 
 logger.debug('Loading app');
diff --git a/components/api-server/src/expressApp.js b/components/api-server/src/expressApp.js
index a76a131a0..add8322f4 100644
--- a/components/api-server/src/expressApp.js
+++ b/components/api-server/src/expressApp.js
@@ -18,6 +18,8 @@ const { getAPIVersion } = require('middleware/src/project_version');
 
 const { getConfig } = require('@pryv/boiler');
 
+const { initExpressTracer } = require('tracing');
+
 // ------------------------------------------------------------ express app init
 
 // Creates and returns an express application with a standard set of middleware. 
@@ -27,6 +29,9 @@ async function expressAppInit(logging) {
   const version = await getAPIVersion();
   const config = await getConfig();
   const app = express(); // register common middleware
+
+  initExpressTracer(app);
+
   const commonHeadersMiddleware = await middleware.commonHeaders();
   const requestTraceMiddleware = middleware.requestTrace(app, logging);
 
diff --git a/components/api-server/src/routes/auth/register.js b/components/api-server/src/routes/auth/register.js
index 6d667aa7e..48420ddfd 100644
--- a/components/api-server/src/routes/auth/register.js
+++ b/components/api-server/src/routes/auth/register.js
@@ -47,13 +47,13 @@ module.exports = function (expressApp: express$Application, app: Application) {
     expressApp.get(path.join(regPath, '/:username/check_username'), 
       setMinimalMethodContext,
       setMethodId('auth.usernameCheck'),
-      (req: express$Request, res, next) => {
+      function apiCall(req: express$Request, res, next) {
         api.call(req.context, req.params, methodCallback(res, next, 200));
     });
     expressApp.get(path.join(regPath, '/:email/check_email'), 
       setMinimalMethodContext,
       setMethodId('auth.emailCheck'),
-      (req: express$Request, res, next) => {
+      function apiCall(req: express$Request, res, next) {
         api.call(req.context, req.params, methodCallback(res, next, 200));
     });
     expressApp.post(path.join(regPath, '/username/check'), (req: express$Request, res, next) => {
diff --git a/components/api-server/src/routes/events.js b/components/api-server/src/routes/events.js
index 17db34c6c..5667683e6 100644
--- a/components/api-server/src/routes/events.js
+++ b/components/api-server/src/routes/events.js
@@ -35,7 +35,7 @@ module.exports = async function(expressApp: express$Application, app: Applicatio
   expressApp.get(Paths.Events + '/',
     setMethodId('events.get'),
     loadAccessMiddleware,
-    function (req: express$Request, res, next) {
+    function coerce(req: express$Request, res, next) {
       const params = _.extend({}, req.query);
       tryCoerceStringValues(params, {
         fromTime: 'number',
@@ -56,7 +56,7 @@ module.exports = async function(expressApp: express$Application, app: Applicatio
   expressApp.get(Paths.Events + '/:id',
     setMethodId('events.getOne'),
     loadAccessMiddleware,
-    function (req: express$Request, res, next) {
+    function coerce(req: express$Request, res, next) {
       const params = _.extend({id: req.params.id}, req.query);
       tryCoerceStringValues(params, {
         includeHistory: 'boolean'
@@ -126,7 +126,7 @@ module.exports = async function(expressApp: express$Application, app: Applicatio
     setMethodId('events.create'),
     loadAccessMiddleware,
     hasFileUpload,
-    function (req: express$Request, res, next) {
+    function apiCall(req: express$Request, res, next) {
       const params = req.body;
       if (req.files) {
         params.files = req.files;
@@ -144,12 +144,12 @@ module.exports = async function(expressApp: express$Application, app: Applicatio
   expressApp.put(Paths.Events + '/:id',
     setMethodId('events.update'),
     loadAccessMiddleware,
-    function (req: express$Request, res, next) {
+    function apiCall(req: express$Request, res, next) {
       api.call(req.context, { id: req.params.id, update: req.body }, methodCallback(res, next, 200));
     });
 
   expressApp.post(Paths.Events + '/stop',
-    function (req: express$Request, res, next) {
+    function apiCall(req: express$Request, res, next) {
       return next(errors.goneResource());
     });
   
@@ -158,7 +158,7 @@ module.exports = async function(expressApp: express$Application, app: Applicatio
     setMethodId('events.update'),
     loadAccessMiddleware,
     hasFileUpload,
-    function (req: express$Request, res, next) {
+    function apiCall(req: express$Request, res, next) {
       const params = {
         id: req.params.id,
         update: {}
@@ -174,14 +174,14 @@ module.exports = async function(expressApp: express$Application, app: Applicatio
   expressApp.delete(Paths.Events + '/:id',
     setMethodId('events.delete'),
     loadAccessMiddleware,
-    function (req: express$Request, res, next) {
+    function apiCall(req: express$Request, res, next) {
       api.call(req.context, {id: req.params.id}, methodCallback(res, next, 200));
     });
 
   expressApp.delete(Paths.Events + '/:id/:fileId',
     setMethodId('events.deleteAttachment'),
     loadAccessMiddleware,
-    function (req: express$Request, res, next) {
+    function apiCall(req: express$Request, res, next) {
       api.call(req.context, {id: req.params.id, fileId: req.params.fileId}, methodCallback(res, next, 200));
     });
 
diff --git a/components/api-server/src/routes/methodCallback.js b/components/api-server/src/routes/methodCallback.js
index 862166548..eb4d1b992 100644
--- a/components/api-server/src/routes/methodCallback.js
+++ b/components/api-server/src/routes/methodCallback.js
@@ -18,7 +18,7 @@ import type Result  from '../Result';
  * @returns {Function}
  */
 module.exports = function (res: express$Response, next: express$NextFunction, successCode: number) {
-  return function (err: ?Error, result: ?Result) {
+  return function methodCallBack(err: ?Error, result: ?Result) {
 
     if (err != null) {
       return next(err);
diff --git a/components/api-server/src/routes/streams.js b/components/api-server/src/routes/streams.js
index e9f6b38ef..7602f09dd 100644
--- a/components/api-server/src/routes/streams.js
+++ b/components/api-server/src/routes/streams.js
@@ -24,7 +24,7 @@ module.exports = function (expressApp: express$Application, app: Application) {
   expressApp.get(Paths.Streams, 
     loadAccessMiddleware,
     setMethodId('streams.get'),
-    function (req: express$Request, res, next) {
+    function coerce (req: express$Request, res, next) {
       const params = _.extend({}, req.query);
       tryCoerceStringValues(params, {
         includeDeletionsSince: 'number'
diff --git a/components/middleware/src/commonHeaders.js b/components/middleware/src/commonHeaders.js
index 524b63b4b..c41d7841b 100644
--- a/components/middleware/src/commonHeaders.js
+++ b/components/middleware/src/commonHeaders.js
@@ -11,9 +11,9 @@ const { getAPIVersion } =  require('middleware/src/project_version');
 // Middleware to handle OPTIONS requests and to add CORS headers to all other 
 // requests. 
 
-module.exports = async function (): Promise<Function> {
+module.exports = async function  (): Promise<Function> {
   const version = await getAPIVersion();
-  return function (req: express$Request, res: express$Response, next: express$NextFunction) {
+  return function commonHeaders(req: express$Request, res: express$Response, next: express$NextFunction) {
     // allow cross-domain requests (CORS)
     res.header('Access-Control-Allow-Origin', req.headers.origin || '*');
     // *
diff --git a/components/middleware/src/contentType.js b/components/middleware/src/contentType.js
index 189541351..13948beca 100644
--- a/components/middleware/src/contentType.js
+++ b/components/middleware/src/contentType.js
@@ -17,7 +17,7 @@ var errors = require('errors').factory;
 function checkContentType(/* arguments */) {
   var acceptedTypes = arguments,
       count = acceptedTypes.length;
-  return function (req, res, next) {
+  return function checkContentType(req, res, next) {
     if (count < 1) { return next(); }
 
     var contentType = req.headers['content-type'];
diff --git a/components/middleware/src/initContext.js b/components/middleware/src/initContext.js
index 6b32df2d3..333945500 100644
--- a/components/middleware/src/initContext.js
+++ b/components/middleware/src/initContext.js
@@ -21,7 +21,7 @@ import type { StorageLayer } from 'storage';
 module.exports = function initContext(
   storageLayer: StorageLayer, customAuthStepFn: ?CustomAuthFunction
 ) {
-  return function (
+  return function initContext(
     req: express$Request, res: express$Response, next: express$NextFunction
   ) {
     const authorizationHeader = req.headers['authorization'];
diff --git a/components/middleware/src/loadAccess.js b/components/middleware/src/loadAccess.js
index aa453c4fc..62f4a8c4d 100644
--- a/components/middleware/src/loadAccess.js
+++ b/components/middleware/src/loadAccess.js
@@ -13,7 +13,7 @@ import type { StorageLayer } from 'storage';
 // Also, it adds the corresponding access id as a specific response header.
 // 
 module.exports = function loadAccess(storageLayer: StorageLayer) {
-  return async function (
+  return async function loadAccess(
     req: express$Request, res: express$Response, next: express$NextFunction
   ) {
 
diff --git a/components/middleware/src/notFound.js b/components/middleware/src/notFound.js
index 64685f0d5..dfd23c8e7 100644
--- a/components/middleware/src/notFound.js
+++ b/components/middleware/src/notFound.js
@@ -9,6 +9,6 @@ const errors = require('errors').factory;
 /**
  * '404' handling to override Express' defaults. Must be set after the routes in the init sequence.
  */
-module.exports = function (req, res, next) {
+module.exports = function notFound(req, res, next) {
   return next(errors.unknownResource());
 };
diff --git a/components/middleware/src/requestTrace.js b/components/middleware/src/requestTrace.js
index f33aabd7a..92378f437 100644
--- a/components/middleware/src/requestTrace.js
+++ b/components/middleware/src/requestTrace.js
@@ -10,7 +10,7 @@
 const morgan = require('morgan');
 const { getLogger } = require('@pryv/boiler');
 
-module.exports = function (express: any) {
+module.exports = function requestTrace(express: any) {
   const logger = getLogger('request-trace');
   const morganLoggerStreamWrite = (msg: string) => logger.info(msg);
   
diff --git a/components/middleware/src/setMethodId.js b/components/middleware/src/setMethodId.js
index 66afc5371..76c232a56 100644
--- a/components/middleware/src/setMethodId.js
+++ b/components/middleware/src/setMethodId.js
@@ -15,9 +15,9 @@ module.exports = function (methodId: string) {
     req: express$Request, res: express$Response, next: express$NextFunction
   ) {
     if (req.context == null) {
-      const tracing = initRootSpan('express2');
+      const tracing = initRootSpan('expressX');
       req.context = {  tracing:  tracing};
-      res.on('finish', () => { tracing.finishSpan('express2', 'e2:' + methodId)} )
+      res.on('finish', () => { tracing.finishSpan('expressX', 'e2:' + methodId)} )
     }
     req.context.methodId = methodId;
     
diff --git a/components/middleware/src/subdomainToPath.js b/components/middleware/src/subdomainToPath.js
index 8f9ccdc14..1130d12c4 100644
--- a/components/middleware/src/subdomainToPath.js
+++ b/components/middleware/src/subdomainToPath.js
@@ -21,7 +21,7 @@ const { USERNAME_REGEXP_STR } = require('api-server/src/schema/helpers');
  * @return {Function}
  */
 module.exports = function (ignoredPaths: Array<string>) {
-  return function (req: express$Request, res: express$Response, next: express$NextFunction) {
+  return function subdomainToPath (req: express$Request, res: express$Response, next: express$NextFunction) {
     if (isIgnoredPath(req.url)) { return next(); }
 
     if (! req.headers.host) { return next(errors.missingHeader('Host')); }
diff --git a/components/tracing/src/expressPatch.js b/components/tracing/src/expressPatch.js
new file mode 100644
index 000000000..a03087dbd
--- /dev/null
+++ b/components/tracing/src/expressPatch.js
@@ -0,0 +1,66 @@
+/**
+ * @license
+ * Copyright (C) 2012-2021 Pryv S.A. https://pryv.com - All Rights Reserved
+ * Unauthorized copying of this file, via any medium is strictly prohibited
+ * Proprietary and confidential
+ */
+
+
+module.exports = function patchApp(app, expressSpanName) {
+  if (app.legacy_use != null) throw new Error('Already patched');
+
+  app.legacy_use = app.use;
+  app.use = function () {
+    const newArgs = [];
+    for (let i = 0; i < arguments.length; i++) {
+      // !!!! doing nothing for now.. all attemp to patch "use" failed
+      newArgs.push(patchFunction0(arguments[i]));
+    }
+    //console.log(arguments, newArgs);
+    return app.legacy_use(...newArgs);
+  }
+
+  patch('get');
+  patch('post');
+  patch('put');
+  patch('delete');
+
+  function patch(key) {
+    app['legacy_' + key] = app[key];
+    app[key] = function () {
+      const newArgs = [arguments[0]];
+      for (let i = 1; i < arguments.length; i++) {
+        const fn = arguments[i];
+        const spanName = 'e:' + key + ':' + arguments[0] + ':' + (fn.name || ('unamed.' + i));
+        newArgs.push(patchFunction(fn, spanName));
+      }
+      return app['legacy_' + key](...newArgs);
+    }
+  }
+
+  function patchFunction(fn, spanName) {
+    return async function (req, res, next) {
+      req.tracing.startSpan(spanName, {}, expressSpanName);
+      return await fn(req, res, function nextCloseSpan(err) {
+        req.tracing.finishSpan(spanName);
+        next(err);
+      });
+    }
+  }
+
+  // doing nothing 
+  function patchFunction0(fn) {
+    console.log('>>>> unpatched: ', fn.name);
+    return fn;
+  }
+
+  // kept for reference
+  function patchFunction2(fn) {
+    // return fn; 
+    if (fn.constructor.name === 'AsyncFunction') {
+      return async () => { try { return await fn.apply(null, arguments); } catch (e) { console.log('XXXX', e) } }
+    }
+    return () => { try { return fn.apply(null, arguments); } catch (e) { console.log(e) } }
+  }
+
+}
\ No newline at end of file
diff --git a/components/tracing/src/index.js b/components/tracing/src/index.js
index b60584904..1f2765ae5 100644
--- a/components/tracing/src/index.js
+++ b/components/tracing/src/index.js
@@ -8,10 +8,10 @@
 
 
 
-const { Tracing, DummyTracing } = require('./Tracing');
+const { Tracing, DummyTracing } = require('./Tracing');
 const { getHookerTracer } = require('./HookedTracer');
 
-
+const expressPatch = require('./expressPatch');
 const dataBaseTracer = require('./databaseTracer');
 const { getConfigUnsafe } = require('@pryv/boiler');
 const isTracingEnabled = getConfigUnsafe(true).get('trace:enable');
@@ -19,8 +19,8 @@ const launchTags = getConfigUnsafe(true).get('trace:tags');
 
 module.exports.DummyTracing = DummyTracing;
 
-module.exports.dataBaseTracer = dataBaseTracer;
 
+module.exports.dataBaseTracer = dataBaseTracer;
 module.exports.getHookerTracer = getHookerTracer;
 
 /**
@@ -42,9 +42,9 @@ module.exports.initRootSpan = initRootSpan;
 /**
  * Returns an ExpressJS middleware that starts a span and attaches the "tracing" object to the request parameter.
  */
-module.exports.tracingMiddleware = (name: string = 'express1', tags: ?{}): Function => {
+function tracingMiddleware (name: string, tags: ?{}): Function  {
   return function (req: express$Request, res: express$Response, next: express$NextFunction): void {
-    if (req.tracing != null) { console.log('XXXXX tracing already set', new Error()); return next();}
+    if (req.tracing != null) { console.log('XXXXX tracing already set', new Error()); return next();}
     const tracing = initRootSpan (name, tags);
     res.on('close', () => { 
       const extra = req.context?.methodId || req.url;
@@ -54,3 +54,10 @@ module.exports.tracingMiddleware = (name: string = 'express1', tags: ?{}): Funct
     next();
   }
 }
+module.exports.tracingMiddleware = tracingMiddleware;
+
+module.exports.initExpressTracer = function(app) {
+  const expressTraceName = 'express2';
+  app.use(tracingMiddleware(expressTraceName)); // anyway .. initRootSpan will retrun a dummytracer is not enabled
+  if (isTracingEnabled) expressPatch(app, expressTraceName);
+}
\ No newline at end of file