diff --git a/test/unit/serverless/api-gateway-v2.test.js b/test/unit/serverless/api-gateway-v2.test.js
index e07a6562ba..d171b91759 100644
--- a/test/unit/serverless/api-gateway-v2.test.js
+++ b/test/unit/serverless/api-gateway-v2.test.js
@@ -64,7 +64,7 @@ test('should pick up the arn', async (t) => {
   assert.equal(agent.collector.metadata.arn, functionContext.invokedFunctionArn)
 })
 
-test('should create a web transaction', (t, end) => {
+test('should create a web transaction', async (t) => {
   const plan = tspl(t, { plan: 8 })
   const { agent, lambda, event, functionContext, responseBody } = t.nr
   agent.on('transactionFinished', verifyAttributes)
@@ -90,21 +90,16 @@ test('should create a web transaction', (t, end) => {
     plan.equal(agentAttributes['request.uri'], '/my/path')
     plan.equal(spanAttributes['request.method'], 'POST')
     plan.equal(spanAttributes['request.uri'], '/my/path')
-
-    end()
   }
+  await plan.completed
 })
 
-test('should set w3c tracecontext on transaction if present on request header', (t, end) => {
+test('should set w3c tracecontext on transaction if present on request header', async (t) => {
   const plan = tspl(t, { plan: 2 })
 
   const expectedTraceId = '4bf92f3577b34da6a3ce929d0e0e4736'
   const traceparent = `00-${expectedTraceId}-00f067aa0ba902b7-00`
   const { agent, lambda, event, functionContext, responseBody } = t.nr
-  agent.on('transactionFinished', () => {
-    end()
-  })
-
   agent.config.distributed_tracing.enabled = true
   event.headers.traceparent = traceparent
 
@@ -124,15 +119,13 @@ test('should set w3c tracecontext on transaction if present on request header',
   })
 
   wrappedHandler(event, functionContext, () => {})
+  await plan.completed
 })
 
-test('should add w3c tracecontext to transaction if not present on request header', (t, end) => {
+test('should add w3c tracecontext to transaction if not present on request header', async (t) => {
   const plan = tspl(t, { plan: 2 })
 
   const { agent, lambda, event, functionContext, responseBody } = t.nr
-  agent.on('transactionFinished', () => {
-    end()
-  })
 
   agent.config.account_id = 'AccountId1'
   agent.config.primary_application_id = 'AppId1'
@@ -152,9 +145,10 @@ test('should add w3c tracecontext to transaction if not present on request heade
   })
 
   wrappedHandler(event, functionContext, () => {})
+  await plan.completed
 })
 
-test('should capture request parameters', (t, end) => {
+test('should capture request parameters', async (t) => {
   const plan = tspl(t, { plan: 5 })
 
   const { agent, lambda, event, functionContext, responseBody } = t.nr
@@ -182,12 +176,11 @@ test('should capture request parameters', (t, end) => {
     plan.equal(spanAttributes['request.parameters.team'], 'node agent')
 
     plan.equal(agentAttributes['request.parameters.parameter1'], 'value1,value2')
-
-    end()
   }
+  await plan.completed
 })
 
-test('should capture request headers', (t, end) => {
+test('should capture request headers', async (t) => {
   const plan = tspl(t, { plan: 2 })
 
   const { agent, lambda, event, functionContext, responseBody } = t.nr
@@ -203,9 +196,8 @@ test('should capture request headers', (t, end) => {
 
     plan.equal(attrs['request.headers.accept'], 'application/json')
     plan.equal(attrs['request.headers.header2'], 'value1,value2')
-
-    end()
   }
+  await plan.completed
 })
 
 test('should not crash when headers are non-existent', (t) => {
diff --git a/test/unit/serverless/aws-lambda.test.js b/test/unit/serverless/aws-lambda.test.js
index 00e529601d..2fd3772379 100644
--- a/test/unit/serverless/aws-lambda.test.js
+++ b/test/unit/serverless/aws-lambda.test.js
@@ -1397,7 +1397,7 @@ test('AwsLambda.patchLambdaHandler', async (t) => {
     }
   )
 
-  await t.test('should record error event when error is thrown', (t, end) => {
+  await t.test('should record error event when error is thrown', async (t) => {
     const plan = tspl(t, { plan: 8 })
     const { agent, awsLambda, error, stubEvent, stubContext, stubCallback } = t.nr
 
@@ -1427,8 +1427,8 @@ test('AwsLambda.patchLambdaHandler', async (t) => {
       if (error.name !== 'SyntaxError') {
         throw error
       }
-      end()
     }
+    await plan.completed
   })
 
   await t.test('should not end transactions twice', (t, end) => {
diff --git a/test/unit/shim/message-shim.test.js b/test/unit/shim/message-shim.test.js
index 30e578c960..00ad948b9e 100644
--- a/test/unit/shim/message-shim.test.js
+++ b/test/unit/shim/message-shim.test.js
@@ -370,7 +370,7 @@ test('MessageShim', async function (t) {
       })
     })
 
-    await t.test('should insert distributed trace headers in all messages', function (t, end) {
+    await t.test('should insert distributed trace headers in all messages', async function (t) {
       const plan = tspl(t, { plan: 1 })
       const { agent, shim, wrappable } = t.nr
       const messages = [{}, { headers: { foo: 'foo' } }, {}]
@@ -418,13 +418,13 @@ test('MessageShim', async function (t) {
           }
         ])
         plan.equal(called, 1)
-        end()
       })
 
       helper.runInTransaction(agent, (tx) => {
         wrappable.sendMessages()
         tx.end()
       })
+      await plan.completed
     })
 
     await t.test('should create message broker metrics', function (t, end) {
@@ -1241,7 +1241,7 @@ test('MessageShim', async function (t) {
       })
     })
 
-    await t.test('should wrap object key of consumer', function (t, end) {
+    await t.test('should wrap object key of consumer', async function (t) {
       const plan = tspl(t, { plan: 4 })
       const { shim } = t.nr
       const message = { foo: 'bar' }
@@ -1267,10 +1267,10 @@ test('MessageShim', async function (t) {
           const segment = shim.getSegment()
           plan.equal(segment.name, 'OtherTransaction/Message/RabbitMQ/Exchange/Named/exchange.foo')
           plan.equal(msg, message)
-          end()
         }
       }
       wrapped(handler)
+      await plan.completed
     })
   })
 })
diff --git a/test/unit/shim/shim.test.js b/test/unit/shim/shim.test.js
index 0e50498b9f..40191d5263 100644
--- a/test/unit/shim/shim.test.js
+++ b/test/unit/shim/shim.test.js
@@ -1184,7 +1184,7 @@ test('Shim', async function (t) {
 
     t.afterEach(afterEach)
 
-    await t.test('should make the segment translucent when promise resolves', function (t, end) {
+    await t.test('should make the segment translucent when promise resolves', async function (t) {
       const plan = tspl(t, { plan: 4 })
       const { agent, promise, resolve, shim, toWrap } = t.nr
       const wrapped = shim.record(toWrap, function () {
@@ -1196,22 +1196,20 @@ test('Shim', async function (t) {
         const ret = wrapped()
         plan.ok(ret instanceof Object.getPrototypeOf(promise).constructor)
 
-        ret
-          .then(function (val) {
-            plan.equal(result, val)
-            plan.equal(promise.segment.opaque, false)
-            end()
-          })
-          .catch(end)
+        ret.then(function (val) {
+          plan.equal(result, val)
+          plan.equal(promise.segment.opaque, false)
+        })
       })
 
       plan.equal(promise.segment.opaque, true)
       setTimeout(function () {
         resolve(result)
       }, 5)
+      await plan.completed
     })
 
-    await t.test('should touch the segment when promise resolves', function (t, end) {
+    await t.test('should touch the segment when promise resolves', async function (t) {
       const plan = tspl(t, { plan: 3 })
       const { agent, promise, resolve, shim, toWrap } = t.nr
       const wrapped = shim.record(toWrap, function () {
@@ -1224,21 +1222,19 @@ test('Shim', async function (t) {
         const oldDur = promise.segment.timer.getDurationInMillis()
         plan.ok(ret instanceof Object.getPrototypeOf(promise).constructor)
 
-        ret
-          .then(function (val) {
-            plan.equal(result, val)
-            plan.ok(promise.segment.timer.getDurationInMillis() > oldDur)
-            end()
-          })
-          .catch(end)
+        ret.then(function (val) {
+          plan.equal(result, val)
+          plan.ok(promise.segment.timer.getDurationInMillis() > oldDur)
+        })
       })
 
       setTimeout(function () {
         resolve(result)
       }, 5)
+      await plan.completed
     })
 
-    await t.test('should make the segment translucent when promise rejects', function (t, end) {
+    await t.test('should make the segment translucent when promise rejects', async function (t) {
       const plan = tspl(t, { plan: 4 })
       const { agent, promise, reject, shim, toWrap } = t.nr
       const wrapped = shim.record(toWrap, function () {
@@ -1250,27 +1246,25 @@ test('Shim', async function (t) {
         const ret = wrapped()
         plan.ok(ret instanceof Object.getPrototypeOf(promise).constructor)
 
-        ret
-          .then(
-            function () {
-              end(new Error('Should not have resolved!'))
-            },
-            function (err) {
-              plan.equal(err, result)
-              plan.equal(promise.segment.opaque, false)
-              end()
-            }
-          )
-          .catch(end)
+        ret.then(
+          function () {
+            throw new Error('Should not have resolved!')
+          },
+          function (err) {
+            plan.equal(err, result)
+            plan.equal(promise.segment.opaque, false)
+          }
+        )
       })
 
       plan.equal(promise.segment.opaque, true)
       setTimeout(function () {
         reject(result)
       }, 5)
+      await plan.completed
     })
 
-    await t.test('should touch the segment when promise rejects', function (t, end) {
+    await t.test('should touch the segment when promise rejects', async function (t) {
       const plan = tspl(t, { plan: 3 })
       const { agent, promise, reject, shim, toWrap } = t.nr
       const wrapped = shim.record(toWrap, function () {
@@ -1288,7 +1282,6 @@ test('Shim', async function (t) {
           function (err) {
             plan.equal(err, result)
             plan.ok(promise.segment.timer.getDurationInMillis() > oldDur)
-            end()
           }
         )
       })
@@ -1296,12 +1289,12 @@ test('Shim', async function (t) {
       setTimeout(function () {
         reject(result)
       }, 5)
+      await plan.completed
     })
 
     await t.test('should not affect unhandledRejection event', async (t) => {
       const plan = tspl(t, { plan: 2 })
       const { agent, promise, reject, shim, toWrap } = t.nr
-      const { promise: testPromise, resolve: testResolve } = promiseResolvers()
       const result = new Error('unhandled rejection test')
 
       tempOverrideUncaught({
@@ -1309,7 +1302,6 @@ test('Shim', async function (t) {
         type: tempOverrideUncaught.REJECTION,
         handler(err) {
           plan.deepEqual(err, result)
-          testResolve()
         }
       })
 
@@ -1328,13 +1320,12 @@ test('Shim', async function (t) {
         reject(result)
       }, 5)
 
-      await testPromise
+      await plan.completed
     })
 
     await t.test('should call after hook when promise resolves', async (t) => {
       const plan = tspl(t, { plan: 7 })
       const { agent, promise, resolve, shim, toWrap } = t.nr
-      const { promise: testPromise, resolve: testResolve } = promiseResolvers()
       const segmentName = 'test segment'
       const expectedResult = { returned: true }
       const wrapped = shim.record(toWrap, function () {
@@ -1349,7 +1340,6 @@ test('Shim', async function (t) {
             plan.equal(error, null)
             plan.deepEqual(result, expectedResult)
             plan.equal(segment.name, segmentName)
-            testResolve()
           }
         })
       })
@@ -1363,13 +1353,12 @@ test('Shim', async function (t) {
         resolve(expectedResult)
       }, 5)
 
-      await testPromise
+      await plan.completed
     })
 
     await t.test('should call after hook when promise reject', async (t) => {
       const plan = tspl(t, { plan: 6 })
       const { agent, promise, reject, shim, toWrap } = t.nr
-      const { promise: testPromise, resolve: testResolve } = promiseResolvers()
       const segmentName = 'test segment'
       const expectedResult = new Error('should call after hook when promise rejects')
       const wrapped = shim.record(toWrap, function () {
@@ -1383,7 +1372,6 @@ test('Shim', async function (t) {
             plan.equal(name, toWrap.name)
             plan.deepEqual(error, expectedResult)
             plan.equal(segment.name, segmentName)
-            testResolve()
           }
         })
       })
@@ -1396,7 +1384,7 @@ test('Shim', async function (t) {
       setTimeout(function () {
         reject(expectedResult)
       }, 5)
-      await testPromise
+      await plan.completed
     })
   })
 
diff --git a/test/versioned/express/app-use.test.js b/test/versioned/express/app-use.test.js
index 1c3d127167..9eff58cd48 100644
--- a/test/versioned/express/app-use.test.js
+++ b/test/versioned/express/app-use.test.js
@@ -9,11 +9,10 @@ const helper = require('../../lib/agent_helper')
 const http = require('http')
 const { isExpress5 } = require('./utils')
 const tsplan = require('@matteo.collina/tspl')
-const promiseResolvers = require('../../lib/promise-resolvers')
 
 // This test is no longer applicable in express 5 as mounting a child router does not emit the same
 // mount event
-test('app should be at top of stack when mounted', { skip: isExpress5() }, function (t, end) {
+test('app should be at top of stack when mounted', { skip: isExpress5() }, async function (t) {
   const agent = helper.instrumentMockedAgent()
   const express = require('express')
 
@@ -28,14 +27,13 @@ test('app should be at top of stack when mounted', { skip: isExpress5() }, funct
 
   child.on('mount', function () {
     plan.equal(main._router.stack.length, 3, '3 middleware functions: query parser, Express, child')
-    end()
   })
 
   main.use(child)
+  await plan.completed
 })
 
 test('app should be at top of stack when mounted', async function (t) {
-  const { promise, resolve } = promiseResolvers()
   const agent = helper.instrumentMockedAgent()
 
   const express = require('express')
@@ -45,19 +43,10 @@ test('app should be at top of stack when mounted', async function (t) {
   const router = new express.Router()
   const router2 = new express.Router()
   const server = http.createServer(main)
-  // track how many requests and wait for all to be done
-  let tests = 0
-
-  const int = setInterval(() => {
-    if (tests === 5) {
-      resolve()
-    }
-  }, 10)
 
   t.after(function () {
     helper.unloadAgent(agent)
     server.close()
-    clearInterval(int)
   })
 
   main.use('/:app', app)
@@ -88,7 +77,6 @@ test('app should be at top of stack when mounted', async function (t) {
           'Expressjs/GET//:app/:child/app',
           'should set partialName correctly for nested apps'
         )
-        ++tests
       })
 
       helper.makeGetRequest(host + '/myApp/nestedApp  ', function (err, res, body) {
@@ -98,7 +86,6 @@ test('app should be at top of stack when mounted', async function (t) {
           'Expressjs/GET//:app/nestedApp',
           'should set partialName correctly for deeply nested apps'
         )
-        ++tests
       })
 
       helper.makeGetRequest(host + '/myApp/myChild/router', function (err, res, body) {
@@ -108,7 +95,6 @@ test('app should be at top of stack when mounted', async function (t) {
           'Expressjs/GET//:router/:child/router',
           'should set partialName correctly for nested routers'
         )
-        ++tests
       })
 
       helper.makeGetRequest(host + '/myApp/nestedRouter', function (err, res, body) {
@@ -118,7 +104,6 @@ test('app should be at top of stack when mounted', async function (t) {
           'Expressjs/GET//:router/nestedRouter',
           'should set partialName correctly for deeply nested routers'
         )
-        ++tests
       })
 
       helper.makeGetRequest(host + '/foo/bar', function (err, res, body) {
@@ -128,7 +113,6 @@ test('app should be at top of stack when mounted', async function (t) {
           'Expressjs/GET//:foo/:bar',
           'should reset partialName after a router without a matching route'
         )
-        ++tests
       })
     })
   })
@@ -137,11 +121,10 @@ test('app should be at top of stack when mounted', async function (t) {
     const tx = agent.getTransaction()
     res.send(tx.id)
   }
-
-  await promise
+  await plan.completed
 })
 
-test('should not pass wrong args when transaction is not present', function (t, end) {
+test('should not pass wrong args when transaction is not present', async function (t) {
   const plan = tsplan(t, { plan: 5 })
 
   const agent = helper.instrumentMockedAgent()
@@ -179,8 +162,8 @@ test('should not pass wrong args when transaction is not present', function (t,
       helper.makeGetRequest('http://localhost:' + port + '/', function (err, res, body) {
         plan.ok(!err)
         plan.equal(body, 'ok')
-        end()
       })
     })
   })
+  await plan.completed
 })
diff --git a/test/versioned/express/bare-router.test.js b/test/versioned/express/bare-router.test.js
index 2b23d78a79..6620487144 100644
--- a/test/versioned/express/bare-router.test.js
+++ b/test/versioned/express/bare-router.test.js
@@ -16,7 +16,7 @@ test.beforeEach(async (ctx) => {
 
 test.afterEach(teardown)
 
-test('Express router introspection', function (t, end) {
+test('Express router introspection', async function (t) {
   const { agent, app, port } = t.nr
   const plan = tsplan(t, { plan: 11 })
 
@@ -53,6 +53,6 @@ test('Express router introspection', function (t, end) {
   helper.makeGetRequest(url, { json: true }, function (error, res, body) {
     plan.equal(res.statusCode, 200, 'nothing exploded')
     plan.deepEqual(body, { status: 'ok' }, 'got expected response')
-    end()
   })
+  await plan.completed
 })
diff --git a/test/versioned/express/errors.test.js b/test/versioned/express/errors.test.js
index a7a4aeb236..7fbf08abc0 100644
--- a/test/versioned/express/errors.test.js
+++ b/test/versioned/express/errors.test.js
@@ -185,7 +185,7 @@ test('Error handling tests', async (t) => {
     })
   })
 
-  await t.test('does not error when request is aborted', function (t, end) {
+  await t.test('does not error when request is aborted', async function (t) {
     const plan = tsplan(t, { plan: 4 })
     const { app, agent, port } = t.nr
     let request = null
@@ -205,7 +205,6 @@ test('Error handling tests', async (t) => {
     app.use(function (error, req, res, next) {
       plan.equal(agent.getTransaction(), null, 'no active transaction when responding')
       res.end()
-      end()
     })
 
     request = http.request(
@@ -222,6 +221,7 @@ test('Error handling tests', async (t) => {
     request.on('error', function (err) {
       plan.equal(err.code, 'ECONNRESET')
     })
+    await plan.completed
   })
 })
 
diff --git a/test/versioned/express/express-enrouten.test.js b/test/versioned/express/express-enrouten.test.js
index 495695a514..40beac47f1 100644
--- a/test/versioned/express/express-enrouten.test.js
+++ b/test/versioned/express/express-enrouten.test.js
@@ -20,7 +20,7 @@ test.beforeEach(async (ctx) => {
 
 test.afterEach(teardown)
 
-test('Express + express-enrouten compatibility test', { skip: isExpress5() }, function (t, end) {
+test('Express + express-enrouten compatibility test', { skip: isExpress5() }, async function (t) {
   const { app, port } = t.nr
   const plan = tsplan(t, { plan: 2 })
 
@@ -35,6 +35,6 @@ test('Express + express-enrouten compatibility test', { skip: isExpress5() }, fu
 
   helper.makeGetRequest('http://localhost:' + port + '/foo', function (error, res) {
     plan.equal(res.statusCode, 200, 'Second Route loaded')
-    end()
   })
+  await plan.completed
 })
diff --git a/test/versioned/express/ignoring.test.js b/test/versioned/express/ignoring.test.js
index e289783d32..72f6f756a7 100644
--- a/test/versioned/express/ignoring.test.js
+++ b/test/versioned/express/ignoring.test.js
@@ -17,7 +17,7 @@ test.beforeEach(async (ctx) => {
 
 test.afterEach(teardown)
 
-test('ignoring an Express route', function (t, end) {
+test('ignoring an Express route', async function (t) {
   const { agent, app, port } = t.nr
   const plan = tsplan(t, { plan: 7 })
 
@@ -57,6 +57,6 @@ test('ignoring an Express route', function (t, end) {
   helper.makeGetRequest(url, function (error, res, body) {
     plan.equal(res.statusCode, 400, 'got expected error')
     plan.deepEqual(body, { status: 'pollpollpoll' }, 'got expected response')
-    end()
   })
+  await plan.completed
 })
diff --git a/test/versioned/express/issue171.test.js b/test/versioned/express/issue171.test.js
index f1671270e2..6169120abc 100644
--- a/test/versioned/express/issue171.test.js
+++ b/test/versioned/express/issue171.test.js
@@ -16,7 +16,7 @@ test.beforeEach(async (ctx) => {
 
 test.afterEach(teardown)
 
-test("adding 'handle' middleware", function (t, end) {
+test("adding 'handle' middleware", async function (t) {
   const { app, port } = t.nr
   const plan = tsplan(t, { plan: 2 })
 
@@ -40,7 +40,7 @@ test("adding 'handle' middleware", function (t, end) {
       res.pipe(process.stderr)
 
       plan.equal(res.statusCode, 500)
-      end()
     })
     .end()
+  await plan.completed
 })
diff --git a/test/versioned/express/render.test.js b/test/versioned/express/render.test.js
index 56443ffc56..49648e6db3 100644
--- a/test/versioned/express/render.test.js
+++ b/test/versioned/express/render.test.js
@@ -45,7 +45,7 @@ test('using only the express router', function (t, end) {
   end()
 })
 
-test('the express router should go through a whole request lifecycle', function (t, end) {
+test('the express router should go through a whole request lifecycle', async function (t) {
   const agent = helper.instrumentMockedAgent()
   const router = require('express').Router() // eslint-disable-line new-cap
   const finalhandler = require('finalhandler')
@@ -70,9 +70,9 @@ test('the express router should go through a whole request lifecycle', function
       server.close()
 
       plan.ok(!error)
-      end()
     })
   })
+  await plan.completed
 })
 
 test('agent instrumentation of Express', async function (t) {
@@ -167,7 +167,8 @@ test('agent instrumentation of Express', async function (t) {
     }
   )
 
-  await t.test('using EJS templates', { timeout: 1000 }, function (t, end) {
+  await t.test('using EJS templates', { timeout: 1000 }, async function (t) {
+    const plan = tsplan(t, { plan: 4 })
     const { app, agent, port } = t.nr
     app.set('views', __dirname + '/views')
     app.set('view engine', 'ejs')
@@ -178,20 +179,20 @@ test('agent instrumentation of Express', async function (t) {
 
     agent.once('transactionFinished', function () {
       const stats = agent.metrics.getMetric('View/index/Rendering')
-      assert.equal(stats.callCount, 1, 'should note the view rendering')
+      plan.equal(stats.callCount, 1, 'should note the view rendering')
     })
 
     helper.makeGetRequest(`${TEST_URL}:${port}${TEST_PATH}`, function (error, response, body) {
-      assert.ok(!error, 'should not error making request')
+      plan.ok(!error, 'should not error making request')
 
-      assert.equal(response.statusCode, 200, 'response code should be 200')
-      assert.equal(body, BODY, 'template should still render fine')
-
-      end()
+      plan.equal(response.statusCode, 200, 'response code should be 200')
+      plan.equal(body, BODY, 'template should still render fine')
     })
+    await plan.completed
   })
 
-  await t.test('should generate rum headers', { timeout: 1000 }, function (t, end) {
+  await t.test('should generate rum headers', { timeout: 1000 }, async function (t) {
+    const plan = tsplan(t, { plan: 5 })
     const { app, agent, port } = t.nr
     const api = new API(agent)
 
@@ -205,23 +206,22 @@ test('agent instrumentation of Express', async function (t) {
 
     app.get(TEST_PATH, function (req, res) {
       const rum = api.getBrowserTimingHeader()
-      assert.equal(rum.substring(0, 7), '<script')
+      plan.equal(rum.substring(0, 7), '<script')
       res.render('index', { title: 'yo dawg', rum })
     })
 
     agent.once('transactionFinished', function () {
       const stats = agent.metrics.getMetric('View/index/Rendering')
-      assert.equal(stats.callCount, 1, 'should note the view rendering')
+      plan.equal(stats.callCount, 1, 'should note the view rendering')
     })
 
     helper.makeGetRequest(`${TEST_URL}:${port}${TEST_PATH}`, function (error, response, body) {
-      assert.ok(!error, 'should not error making request')
-
-      assert.equal(response.statusCode, 200, 'response code should be 200')
-      assert.equal(body, BODY, 'template should still render fine')
+      plan.ok(!error, 'should not error making request')
 
-      end()
+      plan.equal(response.statusCode, 200, 'response code should be 200')
+      plan.equal(body, BODY, 'template should still render fine')
     })
+    await plan.completed
   })
 
   await t.test('should trap errors correctly', function (t, end) {
@@ -491,7 +491,7 @@ test('agent instrumentation of Express', async function (t) {
     })
   })
 
-  await t.test('layer wrapping', function (t, end) {
+  await t.test('layer wrapping', async function (t) {
     const { app, port } = t.nr
     const plan = tsplan(t, { plan: 1 })
     // Add our route.
@@ -507,8 +507,8 @@ test('agent instrumentation of Express', async function (t) {
     // Make our request.
     helper.makeGetRequest(`${TEST_URL}:${port}${TEST_PATH}`, function (err, response, body) {
       plan.equal(body, 'bar', 'should not fail with a proxy layer')
-      end()
     })
+    await plan.completed
   })
 })
 
diff --git a/test/versioned/express/route-iteration.test.js b/test/versioned/express/route-iteration.test.js
index e621d099b9..ed395e31da 100644
--- a/test/versioned/express/route-iteration.test.js
+++ b/test/versioned/express/route-iteration.test.js
@@ -8,7 +8,7 @@ const tsplan = require('@matteo.collina/tspl')
 const test = require('node:test')
 const helper = require('../../lib/agent_helper')
 
-test('new relic should not break route iteration', function (t) {
+test('new relic should not break route iteration', async function (t) {
   const plan = tsplan(t, { plan: 1 })
   const agent = helper.instrumentMockedAgent()
   const express = require('express')
@@ -36,6 +36,7 @@ test('new relic should not break route iteration', function (t) {
   router.use(childB)
 
   plan.deepEqual(findAllRoutes(router, ''), ['/get', ['/test'], ['/hello']])
+  plan.end()
 })
 
 function findAllRoutes(router, path) {
diff --git a/test/versioned/express/route-param.test.js b/test/versioned/express/route-param.test.js
index 447c732369..ba9ce42392 100644
--- a/test/versioned/express/route-param.test.js
+++ b/test/versioned/express/route-param.test.js
@@ -17,7 +17,7 @@ test('Express route param', async function (t) {
 
   t.afterEach(teardown)
 
-  await t.test('pass-through param', function (t, end) {
+  await t.test('pass-through param', async function (t) {
     const { agent, port } = t.nr
     const plan = tsplan(t, { plan: 4 })
 
@@ -33,11 +33,11 @@ test('Express route param', async function (t) {
       plan.ok(!err, 'should not have errored')
       plan.equal(body.action, 'foo', 'should pass through correct parameter value')
       plan.equal(body.name, 'action', 'should pass through correct parameter name')
-      end()
     })
+    await plan.completed
   })
 
-  await t.test('respond from param', function (t, end) {
+  await t.test('respond from param', async function (t) {
     const { agent, port } = t.nr
     const plan = tsplan(t, { plan: 3 })
 
@@ -52,11 +52,11 @@ test('Express route param', async function (t) {
     testRequest(port, 'deny', function (err, body) {
       plan.ok(!err, 'should not have errored')
       plan.equal(body, 'denied', 'should have responded from within paramware')
-      end()
     })
+    await plan.completed
   })
 
-  await t.test('in-active transaction in param handler', function (t, end) {
+  await t.test('in-active transaction in param handler', async function (t) {
     const { agent, port } = t.nr
     const plan = tsplan(t, { plan: 4 })
 
@@ -72,8 +72,8 @@ test('Express route param', async function (t) {
       plan.ok(!err, 'should not have errored')
       plan.equal(body.action, 'preempt', 'should pass through correct parameter value')
       plan.equal(body.name, 'action', 'should pass through correct parameter name')
-      end()
     })
+    await plan.completed
   })
 })
 
diff --git a/test/versioned/express/router-params.test.js b/test/versioned/express/router-params.test.js
index 48831ca964..775fa507a2 100644
--- a/test/versioned/express/router-params.test.js
+++ b/test/versioned/express/router-params.test.js
@@ -21,7 +21,7 @@ test.beforeEach(async (ctx) => {
 
 test.afterEach(teardown)
 
-test('Express router introspection', function (t, end) {
+test('Express router introspection', async function (t) {
   const { agent, app, express, port } = t.nr
   const plan = tsplan(t, { plan: 14 })
 
@@ -64,6 +64,6 @@ test('Express router introspection', function (t, end) {
     plan.ok(!error, 'should not have errored')
     plan.equal(res.statusCode, 200, 'should have ok status')
     plan.deepEqual(body, { status: 'ok' }, 'should have expected response')
-    end()
   })
+  await plan.completed
 })
diff --git a/test/versioned/express/transaction-naming.test.js b/test/versioned/express/transaction-naming.test.js
index bc2a284cf8..eca3baf371 100644
--- a/test/versioned/express/transaction-naming.test.js
+++ b/test/versioned/express/transaction-naming.test.js
@@ -327,7 +327,7 @@ test('transactions running in parallel should be recorded correctly', function (
   }
 })
 
-test('names transaction when request is aborted', function (t, end) {
+test('names transaction when request is aborted', async function (t) {
   const plan = tsplan(t, { plan: 5 })
 
   const { agent, app, port } = t.nr
@@ -349,7 +349,6 @@ test('names transaction when request is aborted', function (t, end) {
   app.use(function (error, req, res, next) {
     plan.ok(agent.getTransaction() == null, 'no active transaction when responding')
     res.end()
-    end()
   })
 
   request = http.request(
@@ -370,9 +369,10 @@ test('names transaction when request is aborted', function (t, end) {
   agent.on('transactionFinished', function (tx) {
     plan.equal(tx.name, 'WebTransaction/Expressjs/GET//test')
   })
+  await plan.completed
 })
 
-test('Express transaction names are unaffected by errorware', function (t, end) {
+test('Express transaction names are unaffected by errorware', async function (t) {
   const plan = tsplan(t, { plan: 1 })
 
   const { agent, app, port } = t.nr
@@ -380,7 +380,6 @@ test('Express transaction names are unaffected by errorware', function (t, end)
   agent.on('transactionFinished', function (tx) {
     const expected = 'WebTransaction/Expressjs/GET//test'
     plan.equal(tx.trace.root.children[0].name, expected)
-    end()
   })
 
   app.use('/test', function () {
@@ -393,9 +392,10 @@ test('Express transaction names are unaffected by errorware', function (t, end)
   })
 
   http.request({ port, path: '/test' }).end()
+  await plan.completed
 })
 
-test('when next is called after transaction state loss', function (t, end) {
+test('when next is called after transaction state loss', async function (t) {
   // Uninstrumented work queue. This must be set up before the agent is loaded
   // so that no transaction state is maintained.
   const tasks = []
@@ -446,7 +446,6 @@ test('when next is called after transaction state loss', function (t, end) {
     res.resume()
     res.on('end', function () {
       plan.equal(transactionsFinished, 2, 'should have two transactions done')
-      end()
     })
   })
 
@@ -457,14 +456,15 @@ test('when next is called after transaction state loss', function (t, end) {
       res.resume()
     })
   }, 100)
+  await plan.completed
 })
 
 // express did not add array based middleware registration
 // without path until 4.9.2
 // https://github.com/expressjs/express/blob/master/History.md#492--2014-09-17
 if (semver.satisfies(pkgVersion, '>=4.9.2')) {
-  test('transaction name with array of middleware with unspecified mount path', (t, end) => {
-    const plan = tsplan(t, { plan: 2 })
+  test('transaction name with array of middleware with unspecified mount path', async (t) => {
+    const plan = tsplan(t, { plan: 3 })
     const { app } = t.nr
 
     function mid1(req, res, next) {
@@ -483,11 +483,12 @@ if (semver.satisfies(pkgVersion, '>=4.9.2')) {
       res.end()
     })
 
-    runTest({ t, end, endpoint: '/path1' })
+    runTest({ t, localAssert: plan, endpoint: '/path1' })
+    await plan.completed
   })
 
-  test('transaction name when ending in array of unmounted middleware', (t, end) => {
-    const plan = tsplan(t, { plan: 2 })
+  test('transaction name when ending in array of unmounted middleware', async (t) => {
+    const plan = tsplan(t, { plan: 3 })
     const { app } = t.nr
 
     function mid1(req, res, next) {
@@ -504,7 +505,8 @@ if (semver.satisfies(pkgVersion, '>=4.9.2')) {
 
     app.use(mid1)
 
-    runTest({ t, end, endpoint: '/path1', expectedName: '/' })
+    runTest({ t, localAssert: plan, endpoint: '/path1', expectedName: '/' })
+    await plan.completed
   })
 }
 
@@ -534,18 +536,32 @@ function makeMultiRunner({ t, endpoint, expectedName, numTests, end }) {
   }
 }
 
-function runTest({ t, endpoint, expectedName, end }) {
+/**
+ * Makes a request and waits for transaction to finish before ending test.
+ * You can pass in the assertion library, this is for tests that rely on `tspl`
+ * end is optionally called and will be ommitted when tests rely on `tspl`
+ * to end.
+ *
+ * @param {object} params to function
+ * @param {object} params.t test context
+ * @param {string} params.endpoint
+ * @param {string} [params.expectedName] defaults to endpoint if not specified
+ * @param {function} [params.end] function that tells test to end
+ * @param {object} params.localAssert library for assertions, defaults to `node:assert`
+ *
+ */
+function runTest({ t, endpoint, expectedName, end, localAssert = require('node:assert') }) {
   const { agent, port } = t.nr
   if (!expectedName) {
     expectedName = endpoint
   }
   agent.on('transactionFinished', function (transaction) {
-    assert.equal(
+    localAssert.equal(
       transaction.name,
       'WebTransaction/Expressjs/GET/' + expectedName,
       'transaction has expected name'
     )
-    end()
+    end?.()
   })
   makeRequest(port, endpoint)
 }