diff --git a/src/app/app.module.ts b/src/app/app.module.ts
index 6e40470..940a3f5 100644
--- a/src/app/app.module.ts
+++ b/src/app/app.module.ts
@@ -1,40 +1,61 @@
 import { BrowserAnimationsModule } from '@angular/platform-browser/animations';
 import { BrowserModule } from '@angular/platform-browser';
-import { EffectsModule } from '@ngrx/effects';
 import { NgModule } from '@angular/core';
+import { ReactiveFormsModule, FormsModule } from '@angular/forms';
+
+import { EffectsModule } from '@ngrx/effects';
 import { StoreModule } from '@ngrx/store';
 
-import { MatToolbarModule } from '@angular/material/toolbar';
-import { MatCardModule } from '@angular/material/card';
+import { MatAutocompleteModule } from '@angular/material/autocomplete';
 import { MatButtonModule } from '@angular/material/button';
+import { MatCardModule } from '@angular/material/card';
+import { MatChipsModule } from '@angular/material/chips';
+import { MatFormFieldModule } from '@angular/material/form-field';
 import { MatIconModule } from '@angular/material/icon';
+import { MatToolbarModule } from '@angular/material/toolbar';
+import { MatInputModule } from '@angular/material/input';
 
 import { AppComponent } from './app.component';
 import { reducers, metaReducers } from './reducers';
 import { CommentStoreModule } from './store';
+import { PipesModule } from './pipes/pipes.module';
+import { DirectivesModule } from './directives/directives.module';
+
 import { CommentCardComponent } from './comment-card/comment-card.component';
 import { CommentsListComponent } from './comments-list/comments-list.component';
-import { PipesModule } from './pipes/pipes.module';
+import { CommentCardEditComponent } from './comment-card-edit/comment-card-edit.component';
+
+const materialModules = [
+  MatAutocompleteModule,
+  MatButtonModule,
+  MatCardModule,
+  MatChipsModule,
+  MatFormFieldModule,
+  MatIconModule,
+  MatToolbarModule,
+  MatInputModule
+];
 
 @NgModule({
   declarations: [
     AppComponent,
     CommentCardComponent,
-    CommentsListComponent
+    CommentsListComponent,
+    CommentCardEditComponent
   ],
   imports: [
     BrowserModule,
     BrowserAnimationsModule,
+    ReactiveFormsModule,
+    FormsModule,
     StoreModule.forRoot(reducers, {
       metaReducers
     }),
     EffectsModule.forRoot([]),
     CommentStoreModule,
-    MatToolbarModule,
-    MatCardModule,
-    MatButtonModule,
-    MatIconModule,
-    PipesModule
+    ...materialModules,
+    PipesModule,
+    DirectivesModule
   ],
   providers: [],
   bootstrap: [AppComponent]
diff --git a/src/app/comment-card-edit/comment-card-edit.component.html b/src/app/comment-card-edit/comment-card-edit.component.html
new file mode 100644
index 0000000..e0cb72b
--- /dev/null
+++ b/src/app/comment-card-edit/comment-card-edit.component.html
@@ -0,0 +1,36 @@
+<mat-card class="comment-card">
+  <form [formGroup]="form" #commentForm="ngForm" (ngSubmit)="submit($event, commentForm)" novalidate>
+    <mat-form-field class="full-width-field">
+      <mat-label>Comment Title</mat-label>
+      <input matInput formControlName="title">
+    </mat-form-field>
+    <mat-form-field class="full-width-field">
+      <mat-chip-list #chipList>
+        <mat-chip *ngFor="let tag of form.value.tags" selectable="true" removable="true" (removed)="removeTag(tag)">
+          {{ tag }}
+          <mat-icon matChipRemove>cancel</mat-icon>
+        </mat-chip>
+        <input placeholder="New tag..." #tagInput [formControl]="tagCtrl" [matAutocomplete]="auto"
+          [matChipInputFor]="chipList" [matChipInputSeparatorKeyCodes]="separatorKeysCodes"
+          (matChipInputTokenEnd)="addTag($event)">
+      </mat-chip-list>
+      <mat-autocomplete #auto="matAutocomplete" (optionSelected)="selected($event)">
+        <mat-option *ngFor="let tag of filteredTags | async" [value]="tag">
+          {{ tag }}
+        </mat-option>
+      </mat-autocomplete>
+    </mat-form-field>
+    <mat-form-field class="full-width-field">
+      <mat-label>Comment Body</mat-label>
+      <textarea matInput rows="6" formControlName="text"></textarea>
+    </mat-form-field>
+    <mat-card-actions align="end">
+      <button mat-button (click)="cancel()">
+        Cancel
+      </button>
+      <button mat-button color="primary" type="submit">
+        {{ !!data?.id ? 'Save' : 'Add' }}
+      </button>
+    </mat-card-actions>
+  </form>
+</mat-card>
\ No newline at end of file
diff --git a/src/app/comment-card-edit/comment-card-edit.component.scss b/src/app/comment-card-edit/comment-card-edit.component.scss
new file mode 100644
index 0000000..1c15ddd
--- /dev/null
+++ b/src/app/comment-card-edit/comment-card-edit.component.scss
@@ -0,0 +1,11 @@
+:host {
+  display: block;
+}
+
+.comment-card {
+  max-width: 420px;
+}
+
+.full-width-field {
+  width: 100%;
+}
\ No newline at end of file
diff --git a/src/app/comment-card-edit/comment-card-edit.component.spec.ts b/src/app/comment-card-edit/comment-card-edit.component.spec.ts
new file mode 100644
index 0000000..2a0cd5f
--- /dev/null
+++ b/src/app/comment-card-edit/comment-card-edit.component.spec.ts
@@ -0,0 +1,25 @@
+import { async, ComponentFixture, TestBed } from '@angular/core/testing';
+
+import { CommentCardEditComponent } from './comment-card-edit.component';
+
+describe('CommentCardEditComponent', () => {
+  let component: CommentCardEditComponent;
+  let fixture: ComponentFixture<CommentCardEditComponent>;
+
+  beforeEach(async(() => {
+    TestBed.configureTestingModule({
+      declarations: [ CommentCardEditComponent ]
+    })
+    .compileComponents();
+  }));
+
+  beforeEach(() => {
+    fixture = TestBed.createComponent(CommentCardEditComponent);
+    component = fixture.componentInstance;
+    fixture.detectChanges();
+  });
+
+  it('should create', () => {
+    expect(component).toBeTruthy();
+  });
+});
diff --git a/src/app/comment-card-edit/comment-card-edit.component.ts b/src/app/comment-card-edit/comment-card-edit.component.ts
new file mode 100644
index 0000000..98ebfe9
--- /dev/null
+++ b/src/app/comment-card-edit/comment-card-edit.component.ts
@@ -0,0 +1,105 @@
+import { COMMA, ENTER } from '@angular/cdk/keycodes';
+import { Component, ElementRef, ViewChild, OnInit, Input } from '@angular/core';
+import { FormBuilder, Validators, FormGroup } from '@angular/forms';
+import { MatAutocompleteSelectedEvent, MatAutocomplete } from '@angular/material/autocomplete';
+import { MatChipInputEvent } from '@angular/material/chips';
+
+import { Observable } from 'rxjs';
+import { map, startWith, withLatestFrom } from 'rxjs/operators';
+
+import { Comment, CommentFacade } from '../store/comment'
+
+@Component({
+  selector: 'app-comment-card-edit',
+  templateUrl: './comment-card-edit.component.html',
+  styleUrls: ['./comment-card-edit.component.scss']
+})
+export class CommentCardEditComponent implements OnInit {
+  @ViewChild('tagInput') tagInput: ElementRef<HTMLInputElement>;
+  @ViewChild('auto') matAutocomplete: MatAutocomplete;
+  @Input() data: Comment;
+  form: FormGroup;
+  tagCtrl = this.fb.control([]);
+  filteredTags: Observable<string[]>;
+  separatorKeysCodes: number[] = [ENTER, COMMA];
+
+  constructor(
+    private readonly fb: FormBuilder,
+    private readonly commentFacade: CommentFacade
+  ) { }
+
+  ngOnInit(): void {
+    if (!!this.data) {
+      this.form = this.fb.group({
+        id: [this.data.id],
+        title: [this.data.title, [Validators.required]],
+        tags: [this.data.tags],
+        text: [this.data.text, [Validators.required]],
+      });
+    } else {
+      this.form = this.fb.group({
+        id: [null],
+        title: [null, [Validators.required]],
+        tags: [[]],
+        text: [null, [Validators.required]],
+      });
+    }
+    this.filteredTags = this.tagCtrl.valueChanges.pipe(
+      startWith(null),
+      withLatestFrom(this.commentFacade.tags$),
+      map(([tag, allTags]) => {
+        if (tag === null) {
+          return [...allTags];
+        }
+        const value = tag.toLowerCase()
+        return allTags.filter(t => t.toLowerCase().includes(value));
+      })
+    );
+  }
+
+  submit(event, commentForm): void {
+    event.preventDefault();
+    if (!!this.form.value.id) {
+      this.commentFacade.edit(this.form.value);
+    } else {
+      this.commentFacade.add(this.form.value);
+    }
+    this.form.reset();
+    commentForm.resetForm();
+  }
+
+  cancel(): void {
+    this.commentFacade.toggleEdit(undefined);
+  }
+
+  selected(event: MatAutocompleteSelectedEvent): void {
+    const tags = [...this.form.value.tags];
+    this.form.get('tags').setValue([...tags, event.option.viewValue]);
+    this.tagInput.nativeElement.value = '';
+    this.tagCtrl.setValue(null);
+  }
+
+
+  addTag(event: MatChipInputEvent): void {
+    const input = event.input;
+    const value = event.value;
+
+    if ((value || '').trim()) {
+      const tags = [...this.form.value.tags];
+      this.form.get('tags').setValue([...tags, value.trim()]);
+    }
+
+    if (input) {
+      input.value = '';
+    }
+
+    this.tagCtrl.setValue(null);
+  }
+
+  removeTag(tag: string): void {
+    const tags = [...this.form.value.tags];
+
+    this.form.get('tags').setValue([...tags.filter(t => t !== tag)]);
+  }
+
+}
diff --git a/src/app/comment-card/comment-card.component.html b/src/app/comment-card/comment-card.component.html
index 949de2e..b095de0 100644
--- a/src/app/comment-card/comment-card.component.html
+++ b/src/app/comment-card/comment-card.component.html
@@ -1,13 +1,17 @@
 <mat-card class="comment-card">
   <mat-card-header>
     <mat-card-title>{{ data.title }}</mat-card-title>
-    <mat-card-subtitle>{{ data.tags | join }}</mat-card-subtitle>
+    <mat-card-subtitle>
+      <mat-chip-list>
+        <mat-chip *ngFor="let tag of data.tags" color="primary" selected>{{ tag }}</mat-chip>
+      </mat-chip-list>
+    </mat-card-subtitle>
   </mat-card-header>
   <mat-card-content>
     <div [innerHTML]="data.text | safeHTML"></div>
   </mat-card-content>
   <mat-card-actions align="end">
-    <button mat-icon-button color="primary" (click)="toggleEdit()">
+    <button mat-button color="primary" (click)="toggleEdit()">
       <mat-icon>edit</mat-icon>
     </button>
     <button mat-icon-button color="warn" (click)="delete()">
diff --git a/src/app/comment-card/comment-card.component.scss b/src/app/comment-card/comment-card.component.scss
index bbc4d0f..3db042f 100644
--- a/src/app/comment-card/comment-card.component.scss
+++ b/src/app/comment-card/comment-card.component.scss
@@ -2,10 +2,6 @@
   display: block;
 }
 
-:host:not(:first-of-type) {
-  margin-top: 1rem;
-}
-
 .comment-card {
   max-width: 420px;
 }
\ No newline at end of file
diff --git a/src/app/comment-card/comment-card.component.ts b/src/app/comment-card/comment-card.component.ts
index 0bd8343..1fc77d5 100644
--- a/src/app/comment-card/comment-card.component.ts
+++ b/src/app/comment-card/comment-card.component.ts
@@ -15,7 +15,7 @@ export class CommentCardComponent {
   ) { }
 
   toggleEdit(): void {
-    // todo
+    this.commentFacade.toggleEdit(this.data.id)
   }
 
   delete(): void {
diff --git a/src/app/comments-list/comments-list.component.html b/src/app/comments-list/comments-list.component.html
index aa11efb..245879d 100644
--- a/src/app/comments-list/comments-list.component.html
+++ b/src/app/comments-list/comments-list.component.html
@@ -1,6 +1,10 @@
 <section class="comment-list" *ngIf="list$ | async as list; else loading;">
-  <ng-container *ngFor="let item of list">
-    <app-comment-card [data]="item"></app-comment-card>
+  <ng-container *ngLet="activeEditId$ | async as activeEditId">
+    <ng-container *ngFor="let item of list">
+      <app-comment-card *ngIf="activeEditId !== item.id" [data]="item"></app-comment-card>
+      <app-comment-card-edit *ngIf="activeEditId === item.id" [data]="item"></app-comment-card-edit>
+    </ng-container>
+    <app-comment-card-edit *ngIf="!activeEditId"></app-comment-card-edit>
   </ng-container>
 </section>
 
diff --git a/src/app/comments-list/comments-list.component.scss b/src/app/comments-list/comments-list.component.scss
index e69de29..1c48435 100644
--- a/src/app/comments-list/comments-list.component.scss
+++ b/src/app/comments-list/comments-list.component.scss
@@ -0,0 +1,5 @@
+.comment-list {
+  *:not(:first-child) {
+    margin-top: 1rem;
+  }
+}
\ No newline at end of file
diff --git a/src/app/comments-list/comments-list.component.ts b/src/app/comments-list/comments-list.component.ts
index 764c4a2..6a31459 100644
--- a/src/app/comments-list/comments-list.component.ts
+++ b/src/app/comments-list/comments-list.component.ts
@@ -9,6 +9,7 @@ import { CommentFacade } from '../store/comment';
 })
 export class CommentsListComponent implements OnInit {
   list$ = this.commentFacade.list$;
+  activeEditId$ = this.commentFacade.activeEditId$;
 
   constructor(
     private readonly commentFacade: CommentFacade
diff --git a/src/app/directives/directives.module.ts b/src/app/directives/directives.module.ts
new file mode 100644
index 0000000..f3bf135
--- /dev/null
+++ b/src/app/directives/directives.module.ts
@@ -0,0 +1,17 @@
+import { NgModule } from '@angular/core';
+
+import { NgLetDirective } from './ng-let-directive';
+
+const exportedDirectives = [
+  NgLetDirective
+];
+
+@NgModule({
+  declarations: [
+    ...exportedDirectives
+  ],
+  exports: [
+    ...exportedDirectives
+  ]
+})
+export class DirectivesModule { }
diff --git a/src/app/directives/ng-let-directive.ts b/src/app/directives/ng-let-directive.ts
new file mode 100644
index 0000000..19e54a6
--- /dev/null
+++ b/src/app/directives/ng-let-directive.ts
@@ -0,0 +1,34 @@
+import {
+  Directive,
+  Input,
+  OnInit,
+  TemplateRef,
+  ViewContainerRef
+} from '@angular/core';
+
+export class NgLetContext {
+  $implicit: any = undefined;
+  ngLet: any = undefined;
+}
+
+@Directive({
+  // tslint:disable-next-line:directive-selector
+  selector: '[ngLet]'
+})
+export class NgLetDirective implements OnInit {
+  private readonly _context = new NgLetContext();
+
+  @Input()
+  set ngLet(value: any) {
+    this._context.$implicit = this._context.ngLet = value;
+  }
+
+  constructor(
+    private readonly _vcr: ViewContainerRef,
+    private readonly _templateRef: TemplateRef<NgLetContext>
+  ) { }
+
+  ngOnInit(): void {
+    this._vcr.createEmbeddedView(this._templateRef, this._context);
+  }
+}
\ No newline at end of file
diff --git a/src/app/store/comment/comment.actions.ts b/src/app/store/comment/comment.actions.ts
index cadb73c..d0a05bd 100644
--- a/src/app/store/comment/comment.actions.ts
+++ b/src/app/store/comment/comment.actions.ts
@@ -16,9 +16,14 @@ export const loadCommentsFailure = createAction(
   '[Comment/API] Load Comments Failure'
 );
 
+export const setCommentEditMode = createAction(
+  '[Comment] Set Comment Edit Mode',
+  props<{ id: number }>()
+);
+
 export const addComment = createAction(
   '[Comment/API] Add Comment',
-  props<{ comment: Comment }>()
+  props<{ comment: Partial<Comment> }>()
 );
 
 export const upsertComment = createAction(
diff --git a/src/app/store/comment/comment.effects.ts b/src/app/store/comment/comment.effects.ts
index fe173d9..c54a1dc 100644
--- a/src/app/store/comment/comment.effects.ts
+++ b/src/app/store/comment/comment.effects.ts
@@ -15,7 +15,7 @@ export class CommentEffects {
       ofType(CommentActions.loadComments),
       switchMap(_ =>
         this.api.getAll().pipe(
-          map(data => CommentActions.loadCommentsSuccess({ comments: data as any })), // debug type issue here
+          map(comments => CommentActions.loadCommentsSuccess({ comments })),
           catchError(_ => of(CommentActions.loadCommentsFailure()))
         )
       )
diff --git a/src/app/store/comment/comment.facade.ts b/src/app/store/comment/comment.facade.ts
index aa732a6..6870b07 100644
--- a/src/app/store/comment/comment.facade.ts
+++ b/src/app/store/comment/comment.facade.ts
@@ -1,23 +1,38 @@
 import { Injectable } from '@angular/core';
 import { Store, select } from '@ngrx/store';
 
-import * as commentActions from './comment.actions';
+import * as CommentActions from './comment.actions';
 import * as query from './comment.selectors'
+import { Comment } from './comment.model';
 
 @Injectable()
 export class CommentFacade {
-  list$ = this.store.pipe(select(query.getAll))
+  list$ = this.store.pipe(select(query.getAll));
+  activeEditId$ = this.store.pipe(select(query.getActiveEditId));
+  tags$ = this.store.pipe(select(query.getAllTags));
 
   constructor(
     private readonly store: Store
   ) { }
 
   getAll(): void {
-    this.store.dispatch(commentActions.loadComments());
+    this.store.dispatch(CommentActions.loadComments());
+  }
+
+  toggleEdit(id: number): void {
+    this.store.dispatch(CommentActions.setCommentEditMode({ id }));
+  }
+
+  add(comment: Partial<Comment>): void {
+    this.store.dispatch(CommentActions.addComment({ comment }))
+  }
+
+  edit(comment: Comment): void {
+    this.store.dispatch(CommentActions.updateComment({ comment: { id: comment.id, changes: comment } }));
   }
 
   delete(id: number): void {
-    this.store.dispatch(commentActions.deleteComment({ id }))
+    this.store.dispatch(CommentActions.deleteComment({ id }))
   }
 
 }
diff --git a/src/app/store/comment/comment.reducer.spec.ts b/src/app/store/comment/comment.reducer.spec.ts
deleted file mode 100644
index bc2ef74..0000000
--- a/src/app/store/comment/comment.reducer.spec.ts
+++ /dev/null
@@ -1,13 +0,0 @@
-import { reducer, initialState } from './comment.reducer';
-
-describe('Comment Reducer', () => {
-  describe('unknown action', () => {
-    it('should return the previous state', () => {
-      const action = {} as any;
-
-      const result = reducer(initialState, action);
-
-      expect(result).toBe(initialState);
-    });
-  });
-});
diff --git a/src/app/store/comment/comment.reducer.ts b/src/app/store/comment/comment.reducer.ts
index d32ee96..20c75a4 100644
--- a/src/app/store/comment/comment.reducer.ts
+++ b/src/app/store/comment/comment.reducer.ts
@@ -1,31 +1,44 @@
-import { Action, createReducer, on } from '@ngrx/store';
+import { createReducer, on } from '@ngrx/store';
 import { EntityState, EntityAdapter, createEntityAdapter } from '@ngrx/entity';
+
 import { Comment } from './comment.model';
 import * as CommentActions from './comment.actions';
 
 export const commentsFeatureKey = 'comments';
 
 export interface State extends EntityState<Comment> {
-  // additional entities state properties
+  activeEditId: number
 }
 
 export const adapter: EntityAdapter<Comment> = createEntityAdapter<Comment>();
 
 export const initialState: State = adapter.getInitialState({
-  // additional entity state properties
+  activeEditId: undefined
 });
 
 
 export const reducer = createReducer(
   initialState,
+  on(CommentActions.setCommentEditMode,
+    (state, action) => ({ ...state, activeEditId: action.id })
+  ),
   on(CommentActions.addComment,
-    (state, action) => adapter.addOne(action.comment, state)
+    (state, action) => {
+      const newComment = {
+        ...action.comment,
+        id: Object.keys(state.entities).length + 1
+      } as Comment;
+      return adapter.addOne(newComment, state)
+    }
   ),
   on(CommentActions.upsertComment,
     (state, action) => adapter.upsertOne(action.comment, state)
   ),
   on(CommentActions.updateComment,
-    (state, action) => adapter.updateOne(action.comment, state)
+    (state, action) => ({
+      ...adapter.updateOne(action.comment, state),
+      activeEditId: undefined
+    })
   ),
   on(CommentActions.deleteComment,
     (state, action) => adapter.removeOne(action.id, state)
@@ -42,3 +55,4 @@ export const {
   selectAll,
   selectTotal,
 } = adapter.getSelectors();
+export const selectActiveEditId = (state: State) => state.activeEditId;
diff --git a/src/app/store/comment/comment.selectors.ts b/src/app/store/comment/comment.selectors.ts
index de0c16b..eb353b7 100644
--- a/src/app/store/comment/comment.selectors.ts
+++ b/src/app/store/comment/comment.selectors.ts
@@ -1,8 +1,9 @@
 import { createFeatureSelector, createSelector } from '@ngrx/store';
 
-import { Comment } from './comment.model';
 import * as fromComment from './comment.reducer';
 
 export const getState = createFeatureSelector<fromComment.State>(fromComment.commentsFeatureKey);
 export const getAll = createSelector(getState, fromComment.selectAll);
-export const getEntities = createSelector(getState, fromComment.selectEntities);
\ No newline at end of file
+export const getEntities = createSelector(getState, fromComment.selectEntities);
+export const getActiveEditId = createSelector(getState, fromComment.selectActiveEditId);
+export const getAllTags = createSelector(getAll, comments => Array.from(new Set(comments.map(c => c.tags).flat()).values()));
\ No newline at end of file
diff --git a/src/app/store/comment/comment.service.ts b/src/app/store/comment/comment.service.ts
index 1cd211d..8c46cfa 100644
--- a/src/app/store/comment/comment.service.ts
+++ b/src/app/store/comment/comment.service.ts
@@ -3,6 +3,8 @@ import { HttpClient } from '@angular/common/http';
 
 import { map } from 'rxjs/operators'
 
+import { Comment } from './comment.model';
+
 @Injectable()
 export class CommentService {
 
diff --git a/tsconfig.json b/tsconfig.json
index 8c4ef3b..d83fada 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -13,6 +13,7 @@
     "target": "es2015",
     "lib": [
       "es2018",
+      "ESNext",
       "dom"
     ]
   },
@@ -20,4 +21,4 @@
     "fullTemplateTypeCheck": true,
     "strictInjectionParameters": true
   }
-}
+}
\ No newline at end of file