What is the SDLC?
The software development life cycle (SDLC) is the series of stages a software project moves through from the first idea to daily use. Knowing the stages helps a business owner understand what the development team is doing, what to expect next and when a decision is needed.
The seven stages
- Planning. The problem, goals, budget and timeline are agreed. Your part: explain the problem and decide the priority.
- Requirement analysis. The team studies how you work today and lists what the software must do. Your part: give access to the staff who do the work.
- Design. Screens, data structure and system layout are drawn before coding starts. Your part: review the screen designs carefully; changes are cheapest here.
- Development. Programmers build the system, usually module by module. Your part: attend the regular demonstrations.
- Testing. The team checks each feature, then you test it with real work. Your part: report problems clearly, with an example.
- Deployment. The software is installed on the live server, old data is moved in and staff are trained.
- Maintenance. Problems are fixed, the system is updated and new features are added as the business changes.
Waterfall and Agile
| Waterfall | Agile | |
|---|---|---|
| How it works | Each stage is finished before the next starts | Work is done in short cycles of one to four weeks |
| When you see the software | Near the end | After every cycle |
| Changes | Difficult once work has started | Expected and planned for |
| Suits | Fixed, well-understood requirements | Projects where needs become clearer over time |
Most business software is best built in an Agile way with a fixed outline: the overall scope and budget are agreed first, and the details are refined cycle by cycle.
Where projects lose time
- Requirements that keep changing because the planning stage was rushed.
- Slow feedback on designs and demonstrations.
- Data that is not ready to be migrated.
- Testing left to the last week.
How long does it take?
A business website takes 3–8 weeks. A custom ERP or school LMS usually takes 3–6 months, delivered module by module. See software development, ERP development and the mistakes to avoid.
