How to use other swift packages in an own swift package?

I'm currently developing a Swift Package in which I would like to use other Swift Packages. To do so I added the packages I want to use to the dependencies in my Package.swift

dependencies: [
    // Dependencies declare other packages that this package depends on.
    // .package(url: /* package url */, from: "1.0.0"),
    .package(url: "https://github.com/jedisct1/swift-sodium.git", .upToNextMajor(from: "0.9.1")),
    .package(url: "https://github.com/Alamofire/Alamofire.git", .upToNextMajor(from: "5.5.0"))
],

This is my full Package.swift:

// swift-tools-version:5.5
// The swift-tools-version declares the minimum version of Swift required to build this package.

import PackageDescription

let package = Package(
    name: "SpaceCryptography",
    platforms: [
        .iOS(.v10),
        .watchOS(.v3)
    ],
    products: [
        // Products define the executables and libraries a package produces, and make them visible to other packages.
        .library(
            name: "SpaceCryptography",
            targets: ["SpaceCryptography"]),
    ],
    dependencies: [
        // Dependencies declare other packages that this package depends on.
        // .package(url: /* package url */, from: "1.0.0"),
        .package(url: "https://github.com/jedisct1/swift-sodium.git", .upToNextMajor(from: "0.9.1")),
        .package(url: "https://github.com/Alamofire/Alamofire.git", .upToNextMajor(from: "5.5.0"))
    ],
    targets: [
        // Targets are the basic building blocks of a package. A target can define a module or a test suite.
        // Targets can depend on other targets in this package, and on products in packages this package depends on.
        .target(
            name: "SpaceCryptography",
            dependencies: []),
        .testTarget(
            name: "SpaceCryptographyTests",
            dependencies: ["SpaceCryptography"]),
    ]
)

The packages then appear under "Package Dependencies" in the Project Navigator. But when I try to use "import Alamofire" I get an error saying "No such module 'Alamofire'". How to properly use these packages in my own package?

As previous mentioned, you have to set the dependencies "Alamofire" and "Sodium" to the target. For example:

.target(
   name: "SpaceCryptography",
   dependencies: ["Alamofire", "Sodium"]),

I recommend to also give names to the dependencies packages defined above:

dependencies: [
        // Dependencies declare other packages that this package depends on.
        // .package(url: /* package url */, from: "1.0.0"),
        .package(name: "Sodium", url: "https://github.com/jedisct1/swift-sodium.git", .upToNextMajor(from: "0.9.1")),
        .package(name: "Alamofire" url: "https://github.com/Alamofire/Alamofire.git", .upToNextMajor(from: "5.5.0"))
    ]