diff --git a/CHANGELOG.md b/CHANGELOG.md
index fdbd26c011c20..ece52bb97ed03 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,8 @@
 
 ## v0.9.0
 
+- [task] allowed running existing tasks with temporary, one-time changes
+
 Breaking changes:
 
 - [plugin] fixed typo in 'HostedInstanceState' enum from RUNNNING to RUNNING in `plugin-dev` extension
diff --git a/packages/plugin-ext/src/plugin/tasks/task-provider.ts b/packages/plugin-ext/src/plugin/tasks/task-provider.ts
index 0a1e12cb8a34f..6fc22fad22019 100644
--- a/packages/plugin-ext/src/plugin/tasks/task-provider.ts
+++ b/packages/plugin-ext/src/plugin/tasks/task-provider.ts
@@ -16,12 +16,9 @@
 
 import * as theia from '@theia/plugin';
 import * as Converter from '../type-converters';
-import { ObjectIdentifier } from '../../common/object-identifier';
 import { TaskDto } from '../../common';
 
 export class TaskProviderAdapter {
-    private cacheId = 0;
-    private cache = new Map<number, theia.Task>();
 
     constructor(private readonly provider: theia.TaskProvider) { }
 
@@ -37,9 +34,6 @@ export class TaskProviderAdapter {
                     continue;
                 }
 
-                const id = this.cacheId++;
-                ObjectIdentifier.mixin(data, id);
-                this.cache.set(id, task);
                 result.push(data);
             }
             return result;
@@ -50,9 +44,7 @@ export class TaskProviderAdapter {
         if (typeof this.provider.resolveTask !== 'function') {
             return Promise.resolve(undefined);
         }
-        const id = ObjectIdentifier.of(task);
-        const cached = this.cache.get(id);
-        const item = cached ? cached : Converter.toTask(task);
+        const item = Converter.toTask(task);
         if (!item) {
             return Promise.resolve(undefined);
         }
diff --git a/packages/task/package.json b/packages/task/package.json
index f38b00a10b9ec..358634eaaeeac 100644
--- a/packages/task/package.json
+++ b/packages/task/package.json
@@ -11,6 +11,7 @@
     "@theia/terminal": "^0.8.0",
     "@theia/variable-resolver": "^0.8.0",
     "@theia/workspace": "^0.8.0",
+    "deepmerge": "2.0.1",
     "jsonc-parser": "^2.0.2"
   },
   "publishConfig": {
diff --git a/packages/task/src/browser/task-frontend-contribution.ts b/packages/task/src/browser/task-frontend-contribution.ts
index ae4fe3eb082e8..d2c09f7566d33 100644
--- a/packages/task/src/browser/task-frontend-contribution.ts
+++ b/packages/task/src/browser/task-frontend-contribution.ts
@@ -179,9 +179,9 @@ export class TaskFrontendContribution implements CommandContribution, MenuContri
                 isEnabled: () => true,
                 // tslint:disable-next-line:no-any
                 execute: (...args: any[]) => {
-                    const [source, label] = args;
+                    const [source, label, overrides] = args;
                     if (source && label) {
-                        return this.taskService.run(source, label);
+                        return this.taskService.run(source, label, overrides);
                     }
                     return this.quickOpenTask.open();
                 }
diff --git a/packages/task/src/browser/task-service.ts b/packages/task/src/browser/task-service.ts
index 45c445b1744ca..e3ac0567e7bb9 100644
--- a/packages/task/src/browser/task-service.ts
+++ b/packages/task/src/browser/task-service.ts
@@ -32,6 +32,8 @@ import { ProvidedTaskConfigurations } from './provided-task-configurations';
 import { Range } from 'vscode-languageserver-types';
 import URI from '@theia/core/lib/common/uri';
 
+const deepmerge: (args: object[]) => object = require('deepmerge').default.all;
+
 @injectable()
 export class TaskService implements TaskConfigurationClient {
     /**
@@ -250,8 +252,11 @@ export class TaskService implements TaskConfigurationClient {
     /**
      * Runs a task, by the source and label of the task configuration.
      * It looks for configured and provided tasks.
+     * The last parameter may contain additional task type specific properties
+     * which are used only for this request over persistent configuration of the task.
      */
-    async run(source: string, taskLabel: string): Promise<void> {
+    // tslint:disable-next-line:no-any
+    async run(source: string, taskLabel: string, overrides?: { [key: string]: any }): Promise<void> {
         let task = await this.getProvidedTask(source, taskLabel);
         if (!task) {
             task = this.taskConfigurations.getTask(source, taskLabel);
@@ -261,6 +266,10 @@ export class TaskService implements TaskConfigurationClient {
             }
         }
 
+        if (overrides) {
+            task = <TaskConfiguration>deepmerge([task, overrides]);
+        }
+
         this.runTask(task);
     }