Music streaming apps have become an essential part of our daily lives. From discovering new indie artists to curating personalized playlists, we rely on these apps to enhance our listening experience. However, building a music app that’s both dynamic and scalable isn’t easy—it requires the right tools and APIs to deliver an engaging experience. As a backend developer, I wanted to create a music app that could tap into a rich library of tracks while offering smooth playback and an intuitive interface. After some research, a couple of other cohort(Terra-learning) developers and I decided to choose the SoundCloud API for its extensive catalog and powerful features. In this post, I’ll take you through my journey of developing the app, the challenges we faced, how I overcame them, and the lessons I learned along the way.
Whether you’re a developer looking to integrate music APIs or just curious about how music apps work behind the scenes, this blog will give you a glimpse into my development process. Let’s dive in! 🎵
What Tech Stack did we use?
To build the music streaming service, we chose a modern, scalable, and developer-friendly tech stack that could handle real-time interactions, efficient data storage, and seamless API integration. Here’s a breakdown of the technologies we used and why they were the best fit for this project
1. Node.js (Runtime Engine)
We used Node.js as the runtime engine for this project because of its non-blocking, event-driven architecture. This made it ideal for handling multiple, concurrent requests—especially important for music streaming services where users expect smooth and uninterrupted playback. Node’s performance and scalability made it a natural choice for this real-time application.
2. Express.js (Web Framework)
To simplify the development of the backend, we used Express.js, a lightweight web framework for Node.js. Express provided a structured way to define routes, handle middleware, and process requests/responses efficiently. Its minimalist design allowed me to easily set up RESTful endpoints to interact with the SoundCloud API and serve dynamic data to the front end.
3. TypeScript (Programming Language)
We chose TypeScript as the primary language because it adds static typing to JavaScript, making the development process more robust and less error-prone. With TypeScript, we could define strict interfaces for data models, catch potential errors during development, and enjoy better code completion and refactoring support. This was particularly beneficial in a project with multiple API interactions and asynchronous operations, where type safety played a critical role.
4. MongoDB (Database)
For data storage, I selected MongoDB, a NoSQL database that’s known for its flexibility and scalability. Since my app needed to store user profiles, playlists, and playback history, MongoDB’s document-based structure was ideal for handling this kind of semi-structured data. Its schema-less nature allowed us to iterate quickly during development without worrying about rigid schema migrations.
MongoDB also scales easily, which is essential for handling a growing user base and large amounts of music data in the future. Its support for fast, complex queries ensured that users could quickly retrieve their playlists and favorites without lag.
5. SoundCloud API (Music Library)
The core feature of the app is its ability to provide users with access to a rich and diverse music library. We chose the SoundCloud API because of its extensive collection of indie and mainstream tracks, along with the ability to search, stream, and curate playlists. SoundCloud’s focus on user-generated content and niche music genres gave my app a unique edge compared to relying solely on mainstream music platforms. Additionally, the SoundCloud API offered comprehensive endpoints for track search, user authentication, and playlist management. Its developer documentation and community support were also strong, which helped speed up the integration process.
API Documentation
This API allows users to interact with music content using the SoundCloud API integration. Users can create and manage playlists, search for songs, and stream music directly from the app.
Stream Song Endpoint
GET /songs/stream/{songId}
Streams a song by its unique ID.
Example Request:GET /songs/stream/song1_id
Response (200 OK)
{
"stream_url": "https://soundcloud.com/stream/song1_id",
"message": "Song is ready to be streamed"
}
Create Playlist Endpoint
POST /music/create-playlist/
Allows users to create a new playlist with a given name and an initial list of song IDs.
Request Body (JSON)
{
"name": "Chill Vibes",
"description": "A playlist of relaxing tracks to unwind and chill out.",
"coverImage": "https://example.com/images/chill-vibes-cover.jpg",
"isPublic": false
}
Response (201 Created)
{
"message": "Playlist created successfully",
"playlist": {
"id": "playlist_id",
"name": "Chill Vibes",
"description": "A playlist of relaxing tracks to unwind and chill out.",
"coverImage": "https://example.com/images/chill-vibes-cover.jpg",
"isPublic": false,
"creator": "{user_id}"
}
}
Search for Song
GET /songs/search
Allows users to search for songs by title, artist, or genre.
Query Parameters:
q(string, required): The search query.genre(string, optional): Filter by music genre.limit(integer, optional): Number of results to return (default is 10).
Example Request:GET /songs/search?q=lofi&limit=5
Response (200 OK)
{
"results": [
{
"id": "song1_id",
"title": "Lo-Fi Beats",
"artist": "Chill Vibes",
"duration": 180000,
"genre": "Lofi",
"stream_url": "https://soundcloud.com/stream/song1_id"
},
{
"id": "song2_id",
"title": "Evening Chill",
"artist": "Relaxation Station",
"duration": 220000,
"genre": "Lofi",
"stream_url": "https://soundcloud.com/stream/song2_id"
}
]
}
Challenges Faces
1. Finding the Right Music Library
One of the first and most critical challenges was identifying a music library that was both free and reliable. Many popular music APIs came with limitations such as restricted access to tracks, limited API calls, or expensive subscription plans.
After extensive research and testing, we settled on the SoundCloud API for several reasons:
Extensive Catalog: SoundCloud offers a vast collection of tracks, from indie artists to niche genres, which align with our app’s goal of music discovery.
User-Generated Content: The platform thrives on unique content uploaded by creators, providing a wide variety of listening options.
Robust Documentation: The API had clear documentation and an active community, making integration easier and more efficient.
2. Streaming Music Data to the User
Streaming music data was another significant challenge. Unlike simple file downloads, streaming requires the delivery of audio data in chunks to ensure continuous playback without overwhelming the user's bandwidth or device. Here’s how we approached it:
Handling Buffering: We implemented a buffering system to ensure that songs load and play smoothly without interruptions. By preloading a few seconds of audio data before starting playback, we minimized pauses due to slow internet connections.
Managing Network Latency: Since users may have varying network speeds, we needed to account for potential latency issues. We optimized the API to deliver smaller chunks of audio data more frequently, reducing the chances of playback stuttering.
Authentication and Access Control: Ensuring that only authorized users could access the streaming service was essential. We implemented token-based authentication to secure each streaming session and prevent unauthorized access.
Lessons I learned
During the brief period that my team and I were able to work on this project, we learned some valuable lessons along the way by overcoming some of the technical challenges and time constraints. Here are the key lessons I learned throughout the process:
Thorough Research Pays Off: Selecting the right tech stack and music library required extensive research. Taking the time to evaluate different APIs and frameworks saved me from running into compatibility and performance issues later.
Type Safety Matters: Using TypeScript was a game-changer. It helped me catch potential bugs early in the development process, improved code readability and made future modifications easier and safer.
Optimize for User Experience: Streaming music is more than just delivering audio data—it’s about ensuring smooth playback, handling network variability, and managing buffering efficiently. Focusing on these details was critical for creating a positive user experience.
Security should be prioritized: Building the project with security in mind made me more aware of opportunities for adding necessary security measures to the project like implementing JWT authentication and securing requests using CORS Headers and so on. It taught me to always think ahead when designing APIs and backend services.
Future Plans for the Project
The current version of the app is functional, but there’s always room for improvement and expansion. Here are the plans for the project:
Open Source Contributions
I plan to open-source the project to encourage community contributions. This will allow other developers to suggest improvements, fix bugs, and add new features. Open sourcing will also make it easier to stay up to date with evolving best practices.Caching for Improved Performance
To further enhance the app’s speed, I’ll implement caching mechanisms to reduce unnecessary API calls. By caching frequently accessed data such as playlists, user profiles, and search results, I can decrease load times and minimize server stress.Asynchronous Task Handling
Asynchronous processing will be introduced to handle background tasks more efficiently. This will allow the app to perform resource-heavy operations (e.g., playlist updates and large data fetches) without blocking user interactions or slowing down the overall experience.Scaling the API
To prepare for potential growth, I plan to:Load Balance API Requests: Distribute incoming requests across multiple servers to prevent overloading a single node.
Database Sharding: Split the database into smaller, more manageable parts to improve performance and reduce query latency.
Containerization: Using Docker to containerize the app will simplify scaling and deployment, ensuring a more consistent and reliable environment across all servers.
Conclusion
Building this music app has been an exciting and insightful journey. From overcoming technical challenges to planning for future growth, I’ve learned so much about backend development, scalability, and API integration. I’m excited to continue improving the app and sharing it with a wider audience. Stay tuned for future updates! 🎵
Check out the Project: https://github.com/Terra-Backend-Team-1/music-api