1. Compilation and Execution: Deno is a runtime for JavaScript and TypeScript, and code written in these languages can be executed directly in Deno without the need for transpiling or bundling. On the other hand, Go is a statically-typed compiled language that requires compilation before execution. This means that Go code needs to be compiled into machine code specific to the target platform before it can be run.
2. Concurrency and Parallelism: Go has built-in support for lightweight threads called goroutines, which enable concurrent programming with ease. It also provides a powerful mechanism called channels for communication and synchronization between goroutines. In contrast, Deno uses JavaScript's event loop for concurrency, which allows for asynchronous non-blocking I/O operations. While Deno supports concurrency through async/await syntax, it does not have built-in support for parallelism like Go.
3. Standard Library: Go has a robust and comprehensive standard library that includes many packages for various purposes, such as networking, file handling, and encryption. Deno, being a secure runtime, has a built-in standard library that focuses on security and provides modules for operations like file system access, HTTP requests, and web server functionality. However, Deno's standard library is still evolving and may not offer the same level of maturity and wide range of packages as Go.
4. Package Management: Go has its own package management system called Go Modules, which is integrated into the Go toolchain. It allows for easy dependency management and versioning. Deno, on the other hand, follows a decentralized approach to package management, where modules are imported using URLs. Deno does not have a centralized package registry and can directly fetch modules from URLs or refer to local files, which provides more flexibility but may lead to potential security concerns.
5. Security Model: Deno has a strong focus on security and provides a secure runtime environment for executing JavaScript and TypeScript code. It includes features like sandboxing, where each module runs in its own secure environment and needs explicit permissions to access system resources. Deno also supports fine-grained permissions for restricting access to file system, network, and environment variables. While Go has built-in security mechanisms like memory safety and general protection against common vulnerabilities, it does not have the same level of isolation and permission control as Deno.
6. Type System: Go is a statically-typed language that enforces strong type checking at compile-time. It provides a simple and efficient type system with support for struct types and interfaces. Deno, being based on TypeScript, has a more expressive and advanced type system that includes features like union types, intersection types, and generics. TypeScript's type annotations allow for better code clarity and enable static analysis for catching type-related errors early in the development process.

In Summary, Deno offers direct execution of JavaScript and TypeScript code, supports asynchronous programming with event loop concurrency, has a security-focused runtime with a evolving standard library, and follows a decentralized package management approach. On the other hand, Go is a statically-compiled language with built-in concurrency support, a robust standard library, integrated Go Modules package management system, and strong memory safety.