refactor: make Red Hat UBI9 image minimal like Ubuntu base

- Simplified Dockerfile to match Ubuntu base image pattern
- Removed multi-stage builds and extensive tooling
- Kept only essential packages: Docker, Git, Python, development tools
- Updated README to reflect minimal base image approach
- Image now serves as extensible base rather than comprehensive environment
- Follows coder/images repository conventions for base images

Author: Blink

images/redhat-ubi9/README.md

@@ -1,69 +1,42 @@
-# Red Hat UBI9 Development Image
+# Red Hat UBI9 Base Image
 
-A comprehensive development workspace image based on Red Hat Universal Base Image 9 (UBI9) for use with Coder.
+[![Docker Pulls](https://img.shields.io/docker/pulls/codercom/enterprise-redhat-ubi9?label=codercom%2Fenterprise-redhat-ubi9)](https://hub.docker.com/r/codercom/enterprise-redhat-ubi9)
+
+## Description
+
+A minimal base image based on Red Hat Universal Base Image 9 (UBI9) for use with Coder workspaces. This image provides enterprise-grade security and compliance while maintaining a minimal footprint.
 
 ## Features
 
 ### Base Operating System
 - **Red Hat UBI9**: Enterprise-grade, security-focused base image
 - **Enterprise Ready**: Red Hat supported with regular security updates
 - **Compliance**: Meets enterprise security and compliance requirements
+- **Minimal**: Only essential packages included
 
-### Development Tools
+### Included Tools
 
-#### Languages & Runtimes
-- **Go 1.24.2**: Latest Go version with complete toolchain
-- **Node.js 20**: Latest LTS with npm and pnpm
-- **Python 3**: System Python with pip
-- **Rust**: Latest stable with Cargo
-
-#### Go Development Tools
-- `gopls` - Go language server
-- `goimports` - Import management
-- `moq` - Mock generation
-- `swag` - Swagger documentation
-- `swagger` - API client generation
-- `migrate` - Database migrations
-- `goreleaser` - Release automation
-- `gotestsum` - Enhanced test output
-- `kind` - Kubernetes in Docker
-- `helm-docs` - Helm documentation
-- `sqlc` - SQL code generation
-- `ruleguard` - Custom linting rules
-- `shfmt` - Shell script formatting
-- `nfpm` - Package building
-- `yq` - YAML processing
-- `mockgen` - Interface mocking
-
-#### Infrastructure & DevOps
+#### Essential Development Tools
+- **Development Tools**: GCC, make, and essential build tools
 - **Docker CE**: Container development and deployment
-- **Terraform**: Infrastructure as Code
-- **kubectl**: Kubernetes command-line tool
-- **Helm**: Kubernetes package manager
-
-#### Development Utilities
 - **Git**: Version control
+- **Python 3**: System Python with pip
+- **Bash**: Default shell
+
+#### System Utilities
+- **curl/wget**: HTTP clients
 - **jq**: JSON processing
 - **htop**: Process monitoring
-- **tmux**: Terminal multiplexer
-- **vim/nano**: Text editors
-- **fish/zsh/bash**: Multiple shell options
-- **pre-commit**: Git hooks framework
-
-#### Rust Tools
-- `jj-cli` - Jujutsu version control
-- `typos-cli` - Spell checker
-- `watchexec-cli` - File watcher
-
-#### Protocol Buffers
-- `protoc` - Protocol buffer compiler
-- Go protobuf plugins
+- **vim**: Text editor
+- **unzip**: Archive extraction
+- **rsync**: File synchronization
+- **systemd**: System and service manager
 
 ## Usage
 
 ### With Coder Templates
 
-Use this image in your Coder workspace templates:
+Use this image as a base in your Coder workspace templates:
 
 ```hcl
 resource "docker_image" "main" {
@@ -79,6 +52,24 @@ resource "docker_container" "workspace" {
 }
 ```
 
+### Extending This Image
+
+Extend this image with additional tooling and language packages:
+
+```dockerfile
+FROM codercom/enterprise-redhat-ubi9
+
+# Install Go
+RUN curl -L "https://go.dev/dl/go1.24.2.linux-amd64.tar.gz" | tar -C /usr/local -xz
+ENV PATH=/usr/local/go/bin:$PATH
+
+# Install Node.js
+RUN curl -fsSL https://rpm.nodesource.com/setup_20.x | bash - && \
+    dnf install -y nodejs
+
+# Add your tools here
+```
+
 ### Building Locally
 
 ```bash
@@ -89,57 +80,44 @@ docker build -f ubi9.Dockerfile -t coder-redhat-ubi9 .
 docker run -it --rm coder-redhat-ubi9
 ```
 
+## How To Use It
+
+Extend this image with additional tooling and language packages.
+
 ### Environment Variables
 
 The image sets up the following environment:
 
-- `GOPATH=/home/coder/go`
-- `GOROOT=/usr/local/go`
-- `PATH` includes Go, Node.js, and all development tools
 - `LANG=en_US.UTF-8`
+- `LANGUAGE=en_US.UTF-8`
 - `LC_ALL=en_US.UTF-8`
 
 ### User Configuration
 
 - **User**: `coder` (non-root)
 - **Home**: `/home/coder`
-- **Shell**: bash (with zsh and fish available)
+- **Shell**: bash
 - **Sudo**: Passwordless sudo access
-
-### Ports
-
-The following ports are exposed for development:
-
-- `3000` - Frontend development servers
-- `8080` - Backend services
-- `8443` - HTTPS services
+- **Groups**: docker (for Docker access)
 
 ## Use Cases
 
-This image is ideal for:
+This base image is ideal for:
 
-- **Go Development**: Complete Go development environment
-- **Full-Stack Development**: Go backend + Node.js frontend
-- **Cloud Native Development**: Kubernetes and container development
-- **Infrastructure Development**: Terraform and DevOps workflows
 - **Enterprise Environments**: Red Hat compliance and support
-- **Multi-language Projects**: Go, Node.js, Python, Rust support
+- **Container Development**: Docker and containerized applications
+- **Custom Development Images**: Extend with specific language runtimes
+- **Security-Conscious Deployments**: Minimal attack surface
+- **Compliance Requirements**: Red Hat enterprise support
 
 ## Security & Compliance
 
 - Based on Red Hat UBI9 for enterprise security
 - Regular security updates from Red Hat
 - Non-root user execution
-- Minimal attack surface with curated tool selection
+- Minimal package installation
 - Compliance with enterprise security policies
 
-## Size Optimization
-
-- Multi-stage build to minimize final image size
-- Package cache cleanup
-- Optimized layer structure
-- Only essential development tools included
-
 ## Support
 
 For issues related to: