Back4app Blog
How to Link Multiple Sign-In Methods to One Account
A signed-in user links a second and third way in, unlinks one, changes a password, signs out everywhere. Every step is a raw REST call to a managed Parse backend, with the codes it answered, and the one case the server lets you break.
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BackendAndroid Expense Tracker App With Source Code: Kotlin, Jetpack Compose and Offline Sync That Is Actually Specified [Full Repo]
A complete Android expense tracker to download and run: Kotlin, Compose, Room, WorkManager and a Parse backend, with an offline sync spec tested cell by cell.
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BackendHow to Build a Scalable Game Backend: Leaderboards & Cloud Saves
Can a general backend-as-a-service run a game's accounts, leaderboards and saves? Built on Parse Server, seeded with a million scores, every query timed.
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BackendWhy Vibe-Coded Apps Break: 13 Problems From 130,000 Posts, Ranked, With the Fix for Each
Why vibe-coded apps break: the 13 problems vibe coders hit most, ranked from annoying to app-killing from 130,000 posts, with the fix for each.
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ContainersHow to Set Up an Invoicing and Bills App Using Only Your Browser
Fork a template, switch on PostgreSQL, open the URL: invoices, bills and a weekly money view on Back4app Containers. No terminal; every number measured.
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BackendHow to Turn a Gantt Spreadsheet Into a Project Tracker Your Team Can Query [Full Repo]
Import the schedule, then ask it what is late and what that blocks. Twelve activities imported in 502 ms, four answers in under half a second each. Oct 2026.
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BackendHow to Ban and Unban Users in Your App, and Make the Ban Stick [Full Repo]
A flag and one trigger blocks the next login — and leaves the banned user signed in, able to clear the flag. The three triggers that close both. Sept 2026.
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ContainersWhy Your App Works Locally and Crashes When You Deploy It [Full Repo]
Four faults an AI coding tool leaves in a working app, each reproduced with its real output, and the one line that fixes each. Oct 2026.
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ContainersHow to Build a Cash Flow Tracker With JavaScript
Demo, full source and deploy guide: a three-screen cash flow tracker with login, server-side rules and no Dockerfile. 159 checks pass on the live backend.
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BackendHow to Find the Nearest Driver in an Uber-Style App [Full Repo]
Store each driver's location and let the database answer who is closest, and how far the trip is. Built and checked in under five seconds, Sept 2026.
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Web DeploymentHow to Deploy a Figma Make Site With an MCP Server [Full Repo]
Generate a site in Figma Make, then ship it from your editor in one prompt. A three-file build went live in 9.4s, Sept 2026.
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BackendHow to Build the Backend for a Flutter App: Login, Data and Push Notifications [Full Repo]
Accounts, per-user notes and push registration for a Flutter app over REST with package:http, no SDK. Create 440 ms, list 420 ms, measured Sept 2026.
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ContainersHow to Host a Flutter Web App With Docker, Without Managing a Server [Full Repo]
Compile a Flutter web build, serve it from nginx in a container, and deploy it from a GitHub repository on the free plan. Measured Sept 2026.
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AI AgentTwo Kinds of AI Agent: One Builds the App, One Operates the Backend
Two agents, two dashboards, two billing models. One builds apps on free daily credits; the other runs on your own OpenAI or Anthropic key. Sept 2026.
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BackendHow to Upload and Serve Images From an App Without S3 [Full Repo]
Upload user images from a web page with two REST calls to a managed backend and serve them from a CDN URL. 1 MB in 6.8 s, 25 MB accepted. Measured Sept 2026.
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ContainersHow to Host a Static Website on Back4app Containers With Docker and nginx [Full Repo]
Put your HTML in a container and deploy it. The usual Dockerfile builds a 254 MB image; the same page ships from 75.9 MB and goes live in 9s. Sept 2026.
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AI AgentHow to Install and Run the BMAD Method in an AI Editor [Artifacts Included]
Install BMAD v6 with the skills CLI, run its planning workflows, and check the output with its own linter. 13 skills in under 7s, Sept 2026.
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BackendWhy Does the API Return 101, 119, 142 or 209? Every Backend Error Code, Reproduced [Full Repo]
Every error code a backend API returns, reproduced with curl: 101, 119, 141, 142, 202, 203, 206, 209 and more, with HTTP status, cause and fix. Sept 2026.
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ContainersHow to Run a Node.js Bot, Webhook or Cron Job 24/7 Without a VPS [Full Repo]
One 75-line Node container ran a signed webhook, a cron tick and a queue worker around the clock, state in a managed backend — measured Sept 2026, no VPS.
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AI AgentHow to Build an Inventory Management System Without Writing Code
Turn your stock spreadsheet into a multi-user inventory system with logins, reorder alerts and an AI assistant — from prompts, in an afternoon. Sept 2026.
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BackendBuild and Deploy a Node.js REST API in 15 Minutes — Without Owning a Server [Full Code Inside]
The same Task API two ways: 105 lines of Express you maintain forever, or 24 lines on Back4app. Measured comparison, every command tested August 2026.
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ContainersHow to Deploy a Next.js SSR App With Docker and a Backend [Full Repo]
Deploy a server-rendered Next.js 15 app with Docker and a managed backend: per-request rendering on a container, keys never in the browser, 6-min first build.
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AI AgentHow to Build an Online Store From a Single Prompt
Describe the shop you want and get a catalogue, cart, checkout, customer accounts and an admin back office — running, with server-side pricing. Sept 2026.
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BackendHow to Add Authentication to a Web or Flutter App Without Writing an Auth Server [Full Repo]
Add signup, login, logout and password reset to a web or Flutter app with six REST calls to a managed backend and no auth server. Signup 597 ms, login 245 ms.
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ContainersHow to Deploy FastAPI With Docker and a Database, Without Managing a Server [Full Repo]
Deploy a FastAPI app with Docker and a managed database: 80 lines of Python, a 7-line Dockerfile, live behind HTTPS in 86 seconds, and the bug Pydantic missed.
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AI AgentHow to Turn a Spreadsheet Into a Web App With a Database and Login
Attach your .xlsx, describe what you need, and get a multi-user web app with a real database, Google sign-in and AI and email integrations. Sept 2026.
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ContainersHow to Deploy a Node.js App With Docker and a Database, Without Managing a Server [Full Repo]
Deploy a Node.js app with Docker and a managed database: a 42-line Express app, an 8-line Dockerfile, live behind HTTPS in 42 seconds, no server to administer.
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BackendYour Frontend Talks Straight to the Database. Here Is How to Lock It Down [Full Repo]
Twelve requests from four identities against one class, before and after class-level permissions, an owner ACL from a hook and a role. Measured Sept 2026.