diff --git a/src/operations/category.service.ts b/src/operations/category.service.ts
index 411d4b7..c7559df 100644
--- a/src/operations/category.service.ts
+++ b/src/operations/category.service.ts
@@ -5,14 +5,14 @@ import * as moment from 'moment';
 import { Injectable } from '@angular/core';
 import { Observable } from 'rxjs/Rx';
 
-import { Restangular } from "ngx-restangular";
+import { HttpClient, HttpParams } from "@angular/common/http";
 
 import { Category } from './category';
 
 @Injectable()
 export class CategoryService {
   constructor(
-    private restangular: Restangular
+    private http: HttpClient
   ) {}
 
   formatDate(date: Date|string) {
@@ -24,16 +24,16 @@ export class CategoryService {
   }
 
   query(id: number, minDate: Date = null, maxDate: Date = null): Observable<Category[]> {
-    var dateRange: any = {};
+    let params: HttpParams = new HttpParams();
 
     if(minDate) {
-      dateRange.begin = this.formatDate(minDate);
+      params = params.set('begin', this.formatDate(minDate));
     }
 
     if(maxDate) {
-      dateRange.end = this.formatDate(maxDate);
+      params = params.set('end', this.formatDate(maxDate));
     }
 
-    return this.restangular.one('account', id).getList('category', dateRange);
+    return this.http.get<Category[]>(`/api/account/${id}/category`, { params: params});
   }
 }
diff --git a/src/operations/operation.module.ts b/src/operations/operation.module.ts
index 2b252ce..fd87ff7 100644
--- a/src/operations/operation.module.ts
+++ b/src/operations/operation.module.ts
@@ -3,9 +3,8 @@
 import { NgModule } from '@angular/core';
 import { CommonModule } from '@angular/common';
 import { FormsModule } from '@angular/forms';
-import { HttpModule } from '@angular/http';
+import { HttpClientModule } from '@angular/common/http';
 
-import { RestangularModule } from 'ngx-restangular';
 import { NgLoggerModule, Level } from '@nsalaun/ng-logger';
 import { NgbModule } from '@ng-bootstrap/ng-bootstrap';
 import { ToastrModule } from 'ngx-toastr';
@@ -31,11 +30,10 @@ export function accountIdServiceFactory(i: any) {
 
 @NgModule({
   imports: [
-    HttpModule,
+    HttpClientModule,
     CommonModule,
     FormsModule,
     NgLoggerModule,
-    RestangularModule,
     ToastrModule,
     NgbModule,
     TextMaskModule
diff --git a/src/operations/operation.service.ts b/src/operations/operation.service.ts
index 5ff0931..0286040 100644
--- a/src/operations/operation.service.ts
+++ b/src/operations/operation.service.ts
@@ -3,26 +3,18 @@
 import * as moment from 'moment';
 
 import { Injectable } from '@angular/core';
-import { Observable } from 'rxjs/Rx';
+import { HttpClient, HttpParams } from '@angular/common/http';
 
-import { Restangular } from "ngx-restangular";
+import { Observable } from 'rxjs/Rx';
 
 import { Operation } from './operation';
 
 @Injectable()
 export class OperationService {
   constructor(
-    private restangular: Restangular
+    private http: HttpClient,
   ) {}
 
-  private all() {
-    return this.restangular.all('operation');
-  }
-
-  private one(id: number) {
-    return this.restangular.one('operation', id);
-  }
-
   formatDate(date: Date|string) {
     if(date instanceof Date) {
       return moment(date).format('YYYY-MM-DD');
@@ -31,39 +23,49 @@ export class OperationService {
     return date;
   }
 
+  url(id?: Number): string {
+    if(id) {
+      return `/api/operation/${id}`;
+    }
+
+    return `/api/operation`;
+  }
+
   query(
     accountId: number,
     minDate: Date|string = null,
     maxDate: Date|string = null
   ): Observable<Operation[]> {
-    var dateRange: any = {
-      account_id: accountId
-    };
+    let params = new HttpParams();
+
+    params = params.set('account_id', `${accountId}`);
 
     if(minDate) {
-      dateRange.begin = this.formatDate(minDate);
+      params = params.set('begin', this.formatDate(minDate));
     }
 
     if(maxDate) {
-      dateRange.end = this.formatDate(maxDate);
+      params = params.set('end', this.formatDate(maxDate));
     }
 
-    return this.all().getList(dateRange);
+    return this.http.get<Operation[]>(this.url(), {
+      params: params
+    });
   }
   
   get(id: number): Observable<Operation> {
-    return this.one(id).get();
+    return this.http.get<Operation>(this.url(id));
   }
 
   create(operation: Operation): Observable<Operation> {
-    return this.all().post(operation);
+    return this.http.post<Operation>(this.url(), operation);
   }
 
   update(operation: Operation): Observable<Operation> {
-    return this.one(operation.id).post(null, operation);
+    return this.http.post<Operation>(this.url(operation.id), operation);
   }
 
   delete(operation: Operation): Observable<Operation> {
-    return this.one(operation.id).remove();
+    return this.http.delete<Operation>(this.url(operation.id));
   }
 }