Composer not making request to private repository

Question

I have a private Satis repository set up on which I am hosting several private packages. I would like to include one of these packages as a dependency for a package I am writing, but when I try to run composer update (with composer version 1.4.1), it is failing with the following message:

Your requirements could not be resolved to an installable set of packages.

Problem 1
    - The requested package my/dependency-bundle could not be found in any version, there may be a typo in the package name.

Potential causes:
 - A typo in the package name
 - The package is not available in a stable-enough version according to your minimum-stability setting
   see <https://getcomposer.org/doc/04-schema.md#minimum-stability> for more details.

Here is my composer.json:

{
    "name":"my/bundle",
    "description":"Provides a simple user provider",
    "version": "3.0.0",
    "keywords":["user", "Symfony2", "bundle"],
    "homepage":"http://my.url.com/",
    "authors": [
        {
            "name": "DIMMSum Information Technology",
            "email": "[email protected]"
        }
    ],
    "repositories": [
        {
            "type": "composer",
            "url": "https://my.url.com/packages/"
        }
    ],
    "require": {
        "php": ">=7.0.1",
        "my/dependency-bundle": "3.x-dev"
    },
    "require-dev": {
        "symfony/framework-bundle": ">=2.8"
    },
    "autoload": {
        "psr-0": { "My\\Bundle": "" }
    },
    "minimum-stability": "dev",
    "target-dir": "My/Bundle"
}

And here is the output of running composer update -vvv:

[vagrant@my-rhel7-vagrant my-bundle]$ composer update -vvv
Reading ./composer.json
Loading config file /home/vagrant/.config/composer/auth.json
Loading config file ./composer.json
Checked CA file /etc/pki/ca-trust/extracted/pem/tls-ca-bundle.pem: valid
Reading /home/vagrant/.config/composer/composer.json
Loading config file /home/vagrant/.config/composer/auth.json
Loading config file /home/vagrant/.config/composer/composer.json
Loading config file /home/vagrant/.config/composer/auth.json
Reading /home/vagrant/.config/composer/auth.json
Reading /home/vagrant/.config/composer/vendor/composer/installed.json
Loading plugin Fxp\Composer\AssetPlugin\FxpAssetPlugin
Running 1.4.1 (2017-03-10 09:29:45) with PHP 7.0.10 on Linux / 3.10.0-514.10.2.el7.x86_64
Loading composer repositories with package information
Downloading https://packagist.org/packages.json
Writing /home/vagrant/.cache/composer/repo/https---packagist.org/packages.json into cache
Updating dependencies (including require-dev)
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/p-provider-2013.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/p-provider-2014.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/p-provider-2015.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/p-provider-2016.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/p-provider-2016-07.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/p-provider-2016-10.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/p-provider-2017-01.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/p-provider-2017-04.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/p-provider-archived.json from cache
Downloading http://packagist.org/p/provider-latest%248a761592e8d13b91d8ab79b2d284f47f569be9a701150af0b762648216abf987.json
Writing /home/vagrant/.cache/composer/repo/https---packagist.org/p-provider-latest.json into cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$framework-bundle.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-doctrine$annotations.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-doctrine$cache.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$asset.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$class-loader.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$config.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$dependency-injection.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$event-dispatcher.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$filesystem.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$finder.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$http-foundation.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$http-kernel.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$polyfill-mbstring.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$routing.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$security-core.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$security-csrf.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$stopwatch.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$templating.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$translation.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-doctrine$lexer.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$polyfill-apcu.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$polyfill-php54.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$polyfill-php55.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-psr$log.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$debug.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-paragonie$random-compat.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$polyfill-php56.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$polyfill-util.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$polyfill-php70.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-ircmaxell$password-compat.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-psr$container.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$cache.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-psr$cache.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-psr$simple-cache.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-phpunit$phpunit.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-doctrine$common.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$expression-language.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$yaml.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$var-dumper.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-phpdocumentor$reflection-docblock.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-phpdocumentor$type-resolver.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$console.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$serializer.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$form.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$property-info.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$validator.json from cache
Reading /home/vagrant/.cache/composer/repo/https---packagist.org/provider-symfony$workflow.json from cache
Resolving dependencies through SAT
Dependency resolution completed in 0.241 seconds
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - The requested package my/dependency-bundle could not be found in any version, there may be a typo in the package name.

Potential causes:
 - A typo in the package name
 - The package is not available in a stable-enough version according to your minimum-stability setting
   see <https://getcomposer.org/doc/04-schema.md#minimum-stability> for more details.

Read <https://getcomposer.org/doc/articles/troubleshooting.md> for further common problems.

As you can see, composer is never even sending a request to my repository.

I have verified the following:

• The package name is spelled correctly
• The URL of my Satis repository is reachable and correct
• Deleting the composer cache does not fix the problem.
• The minimum stability setting is as permissive as possible ("dev").

Why is composer not querying my repository for the dependency package, and what do I need to change to make it include my Satis repository in its list of repositories when resolving dependencies?