feat: Add Fedora, UBI, and Podman-in-Podman templates

.github/workflows/test-pr.yaml

@@ -21,6 +21,9 @@ jobs:
             docker-outside-of-docker: ./**/docker-outside-of-docker/**
             docker-outside-of-docker-compose: ./**/docker-outside-of-docker-compose/**
             docker-in-docker: ./**/docker-in-docker/**
+            fedora: ./**/fedora/**
+            ubi: ./**/ubi/**
+            podman-in-podman: ./**/podman-in-podman/**
             dotnet: ./**/dotnet/**
             dotnet-fsharp: ./**/dotnet-fsharp/**
             dotnet-mssql: ./**/dotnet-mssql/**

src/fedora/.devcontainer/Dockerfile

@@ -0,0 +1,27 @@
+# Fedora base image for Dev Containers
+# [Choice] Fedora version: 43, 42, 41, latest, rawhide
+ARG VARIANT=43
+FROM registry.fedoraproject.org/fedora:${VARIANT}
+
+# Install base packages needed for Dev Container features
+RUN dnf install -y \
+        curl \
+        wget \
+        ca-certificates \
+        findutils \
+        which \
+        tar \
+        gzip \
+        unzip \
+        shadow-utils \
+        procps-ng \
+        sudo \
+        glibc-langpack-en \
+    && dnf clean all
+
+# Set locale to avoid warnings
+ENV LANG=en_US.UTF-8 \
+    LC_ALL=en_US.UTF-8
+
+# Note: The common-utils feature will create the vscode user and install additional tools
+

src/fedora/.devcontainer/devcontainer.json

@@ -0,0 +1,40 @@
+// For format details, see https://aka.ms/devcontainer.json. For config options, see the
+// README at: https://github.com/devcontainers/templates/tree/main/src/fedora
+{
+	"name": "Fedora",
+	"build": {
+		"dockerfile": "Dockerfile",
+		"args": {
+			"VARIANT": "${templateOption:imageVariant}"
+		}
+	},
+
+	// Features to add to the dev container. More info: https://containers.dev/features.
+	// Note: Zsh is installed but Bash remains the default shell (matching official templates)
+	"features": {
+		"ghcr.io/devcontainers/features/common-utils:2": {
+			"installZsh": true,
+			"installOhMyZsh": true,
+			"username": "vscode",
+			"userUid": "1000",
+			"userGid": "1000",
+			"upgradePackages": true
+		},
+		"ghcr.io/devcontainers/features/git:1": {}
+	},
+
+	// Use 'forwardPorts' to make a list of ports inside the container available locally.
+	// "forwardPorts": [],
+
+	// Use 'postCreateCommand' to run commands after the container is created.
+	// "postCreateCommand": "cat /etc/fedora-release",
+
+	// Configure tool-specific properties.
+	// "customizations": {},
+
+	// Uncomment to connect as root instead. More info: https://aka.ms/dev-containers-non-root.
+	// "remoteUser": "root"
+	"remoteUser": "vscode"
+}
+
+

src/fedora/NOTES.md

@@ -0,0 +1,44 @@
+## Using this template
+
+This template creates a Fedora-based development container. Fedora provides cutting-edge packages and is the upstream source for Red Hat Enterprise Linux.
+
+### Fedora Version Options
+
+| Version | Description |
+|---------|-------------|
+| `43` | Fedora 43 (current stable, October 2025) |
+| `42` | Fedora 42 (previous stable) |
+| `41` | Fedora 41 (extended support) |
+| `latest` | Latest stable Fedora release |
+| `rawhide` | Development/unstable version |
+
+### Using with Podman
+
+This template works well with Podman as the container engine. To configure VS Code to use Podman:
+
+```json
+{
+    "dev.containers.dockerPath": "podman"
+}
+```
+
+### Adding Development Tools
+
+You can add language-specific tools using [Dev Container Features](https://containers.dev/features). For example, to add Python:
+
+```json
+"features": {
+    "ghcr.io/devcontainers/features/python:1": {}
+}
+```
+
+Or install packages directly using `dnf`:
+
+```json
+"postCreateCommand": "sudo dnf install -y nodejs golang rust"
+```
+
+### Multi-Architecture Support
+
+Fedora images are available for both `x86_64` and `aarch64` (ARM64/Apple Silicon).
+

src/fedora/devcontainer-template.json

@@ -0,0 +1,28 @@
+{
+    "id": "fedora",
+    "version": "1.0.0",
+    "name": "Fedora",
+    "description": "Simple Fedora container with Git and common utilities installed.",
+    "documentationURL": "https://github.com/devcontainers/templates/tree/main/src/fedora",
+    "publisher": "Dev Container Spec Maintainers",
+    "licenseURL": "https://github.com/devcontainers/templates/blob/main/LICENSE",
+    "options": {
+        "imageVariant": {
+            "type": "string",
+            "description": "Fedora version:",
+            "proposals": [
+                "43",
+                "42",
+                "41",
+                "latest",
+                "rawhide"
+            ],
+            "default": "43"
+        }
+    },
+    "platforms": ["Any"],
+    "optionalPaths": [
+        ".github/*"
+    ]
+}
+

src/podman-in-podman/.devcontainer/Dockerfile

@@ -0,0 +1,97 @@
+# Podman-in-Podman for Dev Containers
+# Allows running containers inside a dev container using Podman
+
+# [Choice] Podman version tag: latest or any version (e.g., v5.7.1, v5.7, v5, 5.7.1)
+# Version tags use 'v' prefix (e.g., v5.7.1, v5.7, v5)
+# The 'v' prefix is optional in input - if you specify '5.7.1', it will be used as 'v5.7.1'
+# For best results, specify the full tag with 'v' prefix (e.g., 'v5.7.1', 'v5.7', 'v5')
+ARG VARIANT=latest
+ARG PODMAN_TAG
+ARG INSTALL_BUILDAH="true"
+ARG INSTALL_SKOPEO="true"
+
+# Official Podman images from quay.io
+# Tag format: quay.io/podman/stable:latest or quay.io/podman/stable:v5.7.1, v5.7, v5, etc.
+# PODMAN_TAG is calculated and passed from devcontainer.json:
+# - 'latest' -> 'latest'
+# - Other versions -> add 'v' prefix if not present (e.g., '5.7.1' -> 'v5.7.1', 'v5.7.1' -> 'v5.7.1')
+# Default to 'latest' if PODMAN_TAG is not provided
+FROM quay.io/podman/stable:${PODMAN_TAG:-latest}
+
+# For official Podman images, Podman is already installed
+# Install additional tools and optional components
+RUN dnf install -y \
+        shadow-utils \
+        sudo \
+        curl \
+        wget \
+        ca-certificates \
+        findutils \
+        which \
+        tar \
+        gzip \
+        unzip \
+        procps-ng \
+        glibc-langpack-en \
+        podman-docker \
+    && dnf clean all
+
+# Install optional tools based on build arguments
+# Note: ARG must be redeclared after FROM to be available in this stage
+ARG INSTALL_BUILDAH
+ARG INSTALL_SKOPEO
+RUN if [ "${INSTALL_BUILDAH}" = "true" ]; then \
+        dnf install -y buildah && dnf clean all; \
+    fi \
+    && if [ "${INSTALL_SKOPEO}" = "true" ]; then \
+        dnf install -y skopeo && dnf clean all; \
+    fi
+
+# Configure subuid/subgid for rootless containers (will be set up by common-utils feature)
+# Using UID/GID 1001 to avoid conflicts with existing users in official Podman image
+RUN echo "vscode:100000:65536" >> /etc/subuid \
+    && echo "vscode:100000:65536" >> /etc/subgid \
+    && echo "1001:100000:65536" >> /etc/subuid \
+    && echo "1001:100000:65536" >> /etc/subgid
+
+# Configure Podman for nested container operation
+RUN mkdir -p /etc/containers \
+    && echo '[containers]' > /etc/containers/containers.conf \
+    && echo 'netns="host"' >> /etc/containers/containers.conf \
+    && echo 'userns="host"' >> /etc/containers/containers.conf \
+    && echo 'ipcns="host"' >> /etc/containers/containers.conf \
+    && echo 'utsns="host"' >> /etc/containers/containers.conf \
+    && echo 'cgroupns="host"' >> /etc/containers/containers.conf \
+    && echo 'log_driver = "k8s-file"' >> /etc/containers/containers.conf \
+    && echo '' >> /etc/containers/containers.conf \
+    && echo '[engine]' >> /etc/containers/containers.conf \
+    && echo 'cgroup_manager = "cgroupfs"' >> /etc/containers/containers.conf \
+    && echo 'events_logger = "file"' >> /etc/containers/containers.conf
+
+# Configure storage
+RUN echo '[storage]' > /etc/containers/storage.conf \
+    && echo 'driver = "overlay"' >> /etc/containers/storage.conf \
+    && echo '' >> /etc/containers/storage.conf \
+    && echo '[storage.options.overlay]' >> /etc/containers/storage.conf \
+    && echo 'mount_program = "/usr/bin/fuse-overlayfs"' >> /etc/containers/storage.conf
+
+# Set locale to avoid warnings
+ENV LANG=en_US.UTF-8 \
+    LC_ALL=en_US.UTF-8
+
+# Create /etc/machine-id if it doesn't exist (required by some tools)
+# This is a dummy machine-id for container environments (32 hex chars, no hyphens per systemd spec)
+RUN if [ ! -f /etc/machine-id ]; then \
+        if [ -f /proc/sys/kernel/random/uuid ]; then \
+            # Convert UUID format to 32-char hex string (remove hyphens) \
+            cat /proc/sys/kernel/random/uuid | tr -d '-' > /etc/machine-id; \
+        elif command -v dbus-uuidgen >/dev/null 2>&1; then \
+            dbus-uuidgen | tr -d '-' > /etc/machine-id; \
+        else \
+            # Fallback: generate 32 hex characters \
+            od -An -N16 -tx1 /dev/urandom | tr -d ' \n' > /etc/machine-id || \
+            echo "00000000000000000000000000000000" > /etc/machine-id; \
+        fi; \
+    fi
+
+# Note: The common-utils feature will create the vscode user

src/podman-in-podman/.devcontainer/devcontainer.json

@@ -0,0 +1,65 @@
+// For format details, see https://aka.ms/devcontainer.json. For config options, see the
+// README at: https://github.com/devcontainers/templates/tree/main/src/podman-in-podman
+{
+	"name": "Podman in Podman",
+	"build": {
+		"dockerfile": "Dockerfile",
+		"args": {
+			"VARIANT": "${templateOption:imageVariant}",
+			"PODMAN_TAG": "${templateOption:imageVariant}",
+			"INSTALL_BUILDAH": "${templateOption:installBuildah}",
+			"INSTALL_SKOPEO": "${templateOption:installSkopeo}"
+		}
+	},
+
+	// Required for nested container operations
+	"runArgs": [
+		"--privileged",
+		"--security-opt", "label=disable"
+	],
+
+	// Persistent storage for container images
+	"mounts": [
+		{
+			"source": "devcontainer-podman-var-lib-${devcontainerId}",
+			"target": "/var/lib/containers",
+			"type": "volume"
+		}
+	],
+
+	// Features to add to the dev container. More info: https://containers.dev/features.
+	// Note: Using UID/GID 1001 to avoid conflicts with podman user in official image
+	// Zsh is installed but Bash remains the default shell (matching official templates)
+	"features": {
+		"ghcr.io/devcontainers/features/common-utils:2": {
+			"installZsh": true,
+			"installOhMyZsh": true,
+			"username": "vscode",
+			"userUid": "1001",
+			"userGid": "1001",
+			"upgradePackages": true
+		},
+		"ghcr.io/devcontainers/features/git:1": {}
+	},
+
+	// Use 'forwardPorts' to make a list of ports inside the container available locally.
+	// "forwardPorts": [],
+
+	// Verify Podman is working (run as root for nested container operations)
+	"postCreateCommand": "sudo podman --version && sudo podman info --format '{{.Host.OCIRuntime.Name}}'",
+
+	// Configure tool-specific properties.
+	"customizations": {
+		"vscode": {
+			"extensions": [
+				"redhat.vscode-yaml"
+			]
+		}
+	},
+
+	// Using root for nested container operations to avoid user namespace issues
+	// This is common for Podman-in-Podman scenarios
+	"remoteUser": "root"
+}
+
+