Maintenance Strategy Framework

How to approach maintenance? Have a handbook, framework or routine to organize the work based on a prioritization. For example, you can prioritize based on the urgency (temporal status) and predictability:

Category Temporal Status Predictability Actions
Now
(Immediate-Critical)		 • Issue is actively occurring
• Failure is ongoing or imminent		 • Fully observable
• Probability ≈ 1.0
• No forecasting needed		 • Do a quick, low-cost fix to keep it safe and functioning
• Avoid expensive replacements unless safety is at risk
• Record what broke and what the full solution would require
• Focus on stopping things from getting worse
Upcoming & Expected
(Predictable-Critical)		 • Failure expected in days or weeks
• Based on wear, inspections, or history		 • High confidence (P > 0.7)
• Supported by trend data or experience		 • Start small: plan the work with important and inexpensive parts
• Defer costly labor until more capital is available
• Spread out effort to avoid a financial spike
• Use estimates and planning to argue for budget now
Upcoming & Unexpected
(Potential-Critical)		 • No current failure
• Some early signs or weak signals
• Could happen in weeks or months		 • Low to moderate confidence (P < 0.5)
• Based on team intuition or anomaly detection		 • Write it down to create shared knowledge
• Monitor it regularly, don’t act yet
• Track changes in case it escalates
• Be ready to act if budget improves
• Design flexible, low-effort responses that can scale later

Questions for maintenance

Here are five main areas with questions to ask when taking over an application for maintenance.

  1. Application Overview and Importance:
    • What are the primary functions of your application?
    • How crucial is it for the business operations and revenue generation?
    • Does it integrate closely with other internal or external services and applications?
  2. Development and Maintenance:
    • Is the application actively under development? If so, can you describe the team’s size, experience, and duration of involvement with this project?
    • Do you allocate a budget specifically for its maintenance?
  3. Testing and Deployment:
    • How updated is your application, and do you possess an automated update mechanism?
    • Is there a comprehensive automated test suite in place that covers essential business functions?
    • Are there parts of the application that cause concern, and do you have the means to address these?
    • Can you describe your deployment process, including details on automation, tools, frequency, and handling of unsuccessful deployments?
  4. Infrastructure and Monitoring:
    • How and where is your application hosted?
    • Do you have systems like CI pipelines, staging servers, and error tracking in place? If so, could you detail the tools and processes associated with them?
  5. Workflow, Documentation, and Anomalies:
    • How do you manage and review code changes, and what systems are in place for task tracking and backlog management?
    • Is there a structured approach to documenting the application and its domain, ensuring ease of maintenance and understanding for new team members?
    • Are there any unique or non-standard features of the application that might be relevant during maintenance tasks?

Finally, see the article on how to upgrade ruby on rails.

Or have a look at the General Checklist

Production

  • Hosting
    • Locations
    • Server(s)
      • Physical
      • Cloud
    • Access to servers
      • Ip address whitelist
      • Authorization / Verification
        • Phone
        • Email
      • Ssh
        • Authorized keys
      • Clean up old account access
    • Disk space
      • Used and free
      • Inodes used and free
      • Who can modify
      • When to modify
      • How to modify
    • File storage
    • Backups
      • Is there an automated database backup?
        • How often?
        • How long are backups kept?
        • Where are backups stored?
        • How to restore a backup?
        • How to test a backup?
      • Is there an automated file backup?
    • CDN
  • Monitoring:
    • Bug/Error monitoring (Sentry)
    • Infra/Hosting monitoring (AppSignal/Elastic/…)
      • Server
      • Database
      • Redis
      • Background processing
      • Email processing
    • Other monitoring in place
      • Custom made
      • Emails
      • 3rd party tools
        • checkly, uptimerobot, pingdom, …
        • Slack webhooks
      • Manual checks
  • Logging
    • Rotation
    • Collection
    • Retention
    • Size
    • Types
      • Server
      • Cron
      • Error
      • Other
  • SSL
    • Domains
    • Renewal procedure
      • Access provision
      • Automatic
  • Application Checklist
    • Documentation for technical team
      • Description of business processes
      • Description of application
      • Deploy processes and scripts
        • For acceptance, staging, test, production
    • API
      • Are API requests being made via a separate subdomain? Api.example.com
    • Configuration is stored in environment variables?
      • Check:
        • No Passwords in the database
        • Env variables are configured
  • Domain names & DNS
    • List
    • Access
    • Payment
  • Transactional Email
  • Payment processing
  • 3rd party integrations, services, plugins, themes, assets, images, fonts

Development

  • Version control
  • Code reviews
  • Test driven development
    • Tests all green?
    • Acceptance / integration / unit / other
    • Coverage
  • Continuous integration
  • Deployment
    • Schedule monday - thursday
  • Programming language
    • version
  • Able to start project locally

Coordination

  • Shared knowledge in directories, or files
  • Work locations, times and schedules for real-time conversation
  • Access to communication; Slack, Email, Telephone