Remote Procedure Calls in Web Development: A Simple Guide
When building modern web applications, you often need different parts of your system to communicate—your frontend needs to talk to your backend, your services need to coordinate with each other, and your APIs need to execute specific operations. Remote Procedure Call (RPC) solves this problem by letting one program execute code on another system as if it were running locally. This guide explains what RPC is, why it matters for web development, and when to use it over alternatives like REST or GraphQL.
Key Takeaways
- RPC lets programs execute functions on remote servers as if they were local calls
- Modern frameworks like gRPC and JSON-RPC simplify implementation for web developers
- Choose RPC for action-oriented operations with controlled client-server environments
- REST and GraphQL serve different needs—the best architecture often combines multiple patterns
What Is RPC and How Does It Work?
Think of RPC like ordering food at a restaurant. You (the client) tell the waiter what you want. The waiter takes your order to the kitchen (the server), where the chef prepares your meal. Once ready, the waiter brings it back to you. You don’t need to know how the kitchen works or even speak the chef’s language—the waiter handles all the communication details.
In technical terms, Remote Procedure Call allows a program to execute a function on a remote server as if it were a local function call. The complexity of network communication gets abstracted away, making distributed systems easier to build.
Key Components of RPC
Every RPC system has four essential components:
- Client: The program requesting the remote procedure execution
- Server: The system that hosts and executes the requested procedure
- Stubs: Client-side and server-side proxies that make remote calls look like local ones
- Serialization: The process of converting data into a format suitable for network transmission
When you make an RPC call, your client stub serializes the function name and parameters, sends them over the network, and the server stub deserializes them, executes the function, and returns the result through the same process in reverse.
Why RPC Matters in Modern Web Development
RPC has become essential for web development because it simplifies how different parts of your application communicate. Instead of manually crafting HTTP requests and parsing responses, developers can call remote functions as naturally as local ones.
Frontend-Backend Communication
In web applications, RPC enables seamless communication between your JavaScript frontend and backend services. Rather than constructing REST endpoints for every operation, you define procedures that your frontend can call directly.
Microservices and Distributed Systems
RPC shines in microservices architectures where services need to communicate frequently. Each service exposes its capabilities as procedures that other services can invoke, creating a clean separation of concerns while maintaining simple integration patterns.
Discover how at OpenReplay.com.
Modern RPC Frameworks
Several frameworks make implementing Remote Procedure Call straightforward:
gRPC uses Protocol Buffers for efficient binary serialization and HTTP/2 for transport. It’s ideal for high-performance microservices that need bidirectional streaming and strong typing across multiple programming languages.
JSON-RPC keeps things simple with JSON payloads over HTTP. It’s lightweight, human-readable, and perfect for web applications that prioritize simplicity over raw performance.
XML-RPC was one of the first widely-adopted RPC protocols. While less common today, it’s still found in legacy systems and situations requiring maximum compatibility.
RPC vs REST vs GraphQL: Choosing the Right Approach
Each communication pattern serves different needs:
Use RPC when:
- You need action-oriented operations (like “calculateTax” or “sendEmail”)
- Performance and low latency are critical
- You control both client and server
- Your operations don’t map cleanly to CRUD operations
Use REST when:
- You’re building resource-oriented APIs
- You need standard HTTP caching
- Wide compatibility with web tools is important
- Your API will be consumed by unknown third parties
Use GraphQL when:
- Clients need flexible data queries
- You’re dealing with complex, nested data structures
- Different clients need different data shapes
- Frontend teams want control over response formats
Advantages and Challenges of RPC
Advantages
Simplicity: RPC makes remote calls feel local, reducing cognitive overhead for developers.
Performance: Binary protocols like gRPC offer better performance than text-based alternatives, with smaller payloads and faster parsing.
Abstraction: Network complexity stays hidden, letting developers focus on business logic rather than communication details.
Challenges
Tight Coupling: RPC creates stronger dependencies between client and server than REST. Changes to procedure signatures can break clients.
Debugging Complexity: When remote calls look like local ones, it’s easy to forget about network failures, latency, and partial failures that don’t exist in local function calls.
Network Latency: Despite the local-call illusion, network round trips still happen. Developers must design with latency in mind, especially for chatty interfaces.
Conclusion
Remote Procedure Call remains a powerful pattern for web development, especially when building internal services, microservices architectures, or performance-critical applications. While REST and GraphQL excel at building public APIs and flexible data queries, RPC provides the most straightforward path for executing specific operations across distributed systems. Choose RPC when you need simple, fast, action-oriented communication between services you control—and remember that the best architecture often combines multiple patterns to leverage each one’s strengths.
FAQs
RPC abstracts network communication to make remote function calls appear local. Unlike HTTP APIs where you manually construct requests and parse responses, RPC handles serialization, transport, and deserialization automatically, letting you call remote functions like local ones.
While possible, RPC works best for internal services you control. Public APIs benefit more from REST or GraphQL due to their standardization, documentation tools, and broader client compatibility. RPC's tight coupling makes it less suitable for third-party integrations.
gRPC typically outperforms REST by 2-10x depending on payload size and network conditions. It uses binary Protocol Buffers instead of JSON, HTTP/2 for multiplexing, and supports streaming. These features reduce bandwidth usage and latency significantly.
RPC frameworks provide built-in error handling mechanisms. Define clear error codes and messages in your procedures, implement retry logic with exponential backoff for transient failures, and use circuit breakers to prevent cascading failures in distributed systems.
Understand every bug
Uncover frustrations, understand bugs and fix slowdowns like never before with OpenReplay — the open-source session replay tool for developers. Self-host it in minutes, and have complete control over your customer data. Check our GitHub repo and join the thousands of developers in our community.
