After over a decade leading quality assurance initiatives for Fortune 500 companies, I‘ve seen hundreds of ways testing strategies succeed and fail. When done right, testing uncovers the defects that degrade customer experiences early so your software stays resilient. But testing done inefficiently slows releases while leaving bugs lurking.
This guide draws from my battle-tested experience to equip you with an insider’s perspective for creating a testing approach that finds critical bugs quickly without slowing innovation. I’ll unpack the key testing strategies top dev teams rely on and how to apply them based on context.
By the end, you’ll be ready to assess your team’s needs, pick the right techniques, and sell skeptics on supporting testing. Let‘s get started!
Why Software Testing Demands a Strategic Approach
Before diving into specific testing techniques, it‘s worth grounding ourselves on why testing merits heavy investment. Many developers see testing as a necessary evil that slows their productivity. But modern applications grow incredibly complex; testing is the only scalable way to prevent seemingly small defects from triggering catastrophic failures once software goes live.
Consider this – a recent study found the average hourly cost of critical application failure stands at $300K, accruing from disrupted business operations, reduced revenue, and damage control efforts. And that excludes indirect brand reputation loss and customer churn!
Here are telling statistics that quantify how pervasive software problems remain today:
- 50% of mobile apps demonstrate at least 2 quality issues to end users
- Software bugs cost the US economy $60 billion annually
- 45% of enterprise DevOps initiatives cite issues in test strategy skills
- Financial losses from software failures will reach $2.26 trillion by 2025
The incentives to bolster software testing keep growing exponentially as technology underpins more critical business functions. Strategic testing is no longer optional. Prioritizing testing early sniffs out the defects most likely to frustrate customers in production systems.
Now let‘s explore proven techniques to bake quality directly into your team’s development lifecycle.
Software Testing Strategies for Structuring What to Test
Test strategy guides what parts of an application to focus on validating. Like medical triage in an emergency, you must prioritize areas that pose the biggest risk if broken before releases. The techniques below help categorize testing efforts by different quality attributes and system components.
#1: Functional Testing
Validating that intended application behavior works without defects seems basic but gets forgotten as teams race to push code. Functional testing confirms each system requirement operates correctly from an end user perspective early, including:
- Application workflows across key usage scenarios
- Calculations, data processing, and business logic
- User interfaces, forms, and reporting
- Integrations with external services/databases/networks
Manual testers play an indispensable role guiding exploratory testing to find gaps between software behavior and business intent. They serve as proxy users interpreting requirements.
Add automated UI tests later once user workflows stabilize to prevent functionality regressions during ongoing development. Frame these tests around central use cases and riskier areas.
Smart Tip: Decompose requirements into small testable units. This simplifies tracing tests back to specifications and measuring test coverage.
#2: Non-functional Testing
While functional tests focus on outcomes, non-functional criteria gauge systemic quality attributes governing how software operates under duress like:
Performance – Response times, load capacity, scalability
Security – Vulnerabilities, authentication, protections
Reliability – Crash rates, data integrity, resilience
Usability – Ease-of-use, accessibility compliance
Testing early for non-functional risks helps avoid reinventing temporary band-aid solutions later that accrue technical debt. Deeply analyze architecture and infrastructure plans through fault tree analysis to determine failure scenarios.
Security demands continuous testing via static analysis, penetration testing, and runtime Application Protection solutions to address constantly evolving threats.
63% of breached organizations took months to discover security defects allowing incidents that ultimately cost millions. Prioritize testing security early.
#3: Platform and Device Testing
With tech usage fragmented across mobile, web, and apps, testing software across targeted user platforms grows critical to ensure broad access. Prioritize devices based on market share data and customer personas.
Confirm UI adaptations work properly across form factors. Leverage real device cloud platforms to access thousands of unique hardware, OS, and browser combinations impossible to replicate otherwise. Run automated tests in parallel to validate quickly.
Analyze usage analytics post-launch to guide enhancing platform support coverage. Mobile dominates traffic but overlooked categories like gaming consoles see highly engaged users.
Tip: Budget access to at least the top 5 devices per platform category matching your core demographics.
#4: Regression Testing
Regression testing validates existing features still operate correctly after code changes. This protects against unintended side effects that break functionality users rely on.
Automated regression test suites provide an efficient safeguard by codifying critical user pathways early. Rerun them for rapid feedback with each code check-in and release. Analyze regression testing metrics to pinpoint fragile areas prone to breakage.
Industry research found over 50% of application defects originate from inadequate regression testing around code changes. Automate tests for production usage patterns.
Choosing the Right Manual and Automated Testing Approaches
Complementary approaches execute functional and non-functional test strategies faster and more thoroughly. Choose techniques based on context since no single method fits every situation.
Getting the Most from Manual Testing
Manual testers serve a vital role representing how real users interact with software. Dynamic human exploration uncovers gaps scripted tests miss. Focus manual testing on:
- User Acceptance Validation – Confirm newly developed features match requirements
- Exploratory Testing – Improvise tests beyond defined use cases
- Usability Testing – Assess intuitive navigation and interfaces
- Corner Case Evaluation – Test edge scenarios and invalid inputs
Optimizing manual testing productivity involves:
- Decomposing user stories into discrete test cases
- Checking test steps against requirements traceability
- Using session logging to document test case execution
- Logging detailed defect reports tied to test cases
Without clear test documentation, crucial context gets lost once issues move downstream. Structure manual testing processes to maximize analyzable artifacts.
Implementing Automated Testing Right
Many quality initiatives derail by blindly automating bloated manual test packs verbatim without considering value, scope or maintenance costs. Shifting left through test automation only succeeds with deliberate vision and engineering.
Frame your test automation strategy by assessing:
- Functionality Stability – Avoid automating unfinished features still in flux
- Execution Frequency – Tests running often justify automation
- Time Savings – Prioritize repetitive tests lasting hours manually
- Business Risk – Automate systemically important user pathways
Architect test code for resilience by:
- Encapsulating separate test components behind clean interfaces
- Separating test data from core logic for easy experimentation
- Abstracting hardware-specific selectors to improve portability
- Optimizing speed through test parallelization techniques
Once tests run reliably, shift automation leftwards to amplify feedback:
- During development – Add component unit tests as code gets built
- Continuous integration – Execute full regression test suites with each code merge
- Release gates – Include tests as go/no-go promotion criteria
Automated testing demands meticulous API and integration contract management between layers. Enforce test discipline through coaching and code reviews.
Adopting a Test-Driven Development Approach
Test-driven development (TDD) takes test automation to the next level by forcing developers to author failing test scripts even before writing a single line of application code. This flips testing from an afterthought to something that shapes implementation directly.
Here is the TDD cycle in practice:
- Write a failing automated test for the next required behavior
- Run test suites, verify new test fails showing red/broken status
- Write minimal production code to pass just the failing test
- Repeat steps to build features incrementally test-first
Benefits gained through TDD processes:
- Built-in Safety Net – Gain extensive automated regression test coverage by default
- Rapid Iterations – Isolate code changes to small steps that take minutes
- Emergent Design – Let tests drive more modular code encouraged through refactoring
- Defect Prevention – Fix bugs preemptively before users even see issues
- Documentation – Tests describe how code should function
Success with TDD relies on developers practicing discipline in layering incremental changes over a comprehensive test bed from the very start. It slows initial development but pays off later through dramatically fewer defects and technical debt.
Note: TDD suits agile models emphasizing iterative design improvement. For sequenced waterfall projects, use context-appropriate testing techniques.
Key Criteria for Selecting Testing Strategies
There is no universal playbook prescribing exactly which testing strategies teams must follow. Choosing techniques depends on weighing several contextual factors:
Timelines – Balance testing scope with schedule constraints
Budgets – Prioritize test coverage based on viable resourcing
System Risk – Test riskier aspects more rigorously
Team Skills – Match testing methods to existing capabilities
Delivery Cadence – Tailor strategy across agile sprints vs waterfall releases
With experience, you intuitively learn which testing types work for given project traits and team strengths. There is no replacement for seasoned judgment.
Conduct risk analysis on requirements and architecture plans to guide early test planning. High risk areas likely demand thorough functional and security testing. Lower risk chunks help calibrate automation scopes for expedited feedback without over-engineering.
Discuss test strategy trade-offs transparently with stakeholders and management through show and tells to align expectations. Testing involves balancing prudent quality gates against market urgencies.
Leveraging Real Device Cloud Testing
The expanding landscape of user devices and platforms makes testing software universally challenging. Just procuring ranges of real mobile devices internally scales infeasibly due to costs and overhead.
Fortunately, real device cloud testing services grant on-demand access to thousands of unique phone, tablet and desktop browser combinations hosted in data centers for distributed test execution.
Cloud-based real devices offer numerous advantages over only using internal labs or emulators/simulators:
Broader Test Coverage – Evaluate across more platforms than feasible internally
Time and Cost Savings – Reduce expenditures on lab equipment and maintenance
Flexibility – Scale test runs elastically on-demand
Improved Analytics – Usage metrics reveal how to refine platform support
Integrate these devices early during continuous integration to run full test suites in parallel against every code change. Fix issues promptly before functionality diverges widely.
Optimally combine real devices, emulators, and simulators matched appropriately. Simulators work for validating core functionality. Real devices help confirm realistic end user experiences across targeted deployment environments.
Key Takeaways from an Expert Perspective
We covered extensive ground mapping out tips only gained through weathering countless testing battles over many years. Let me leave you with actionable parting advice:
Start Testing Early
Shifting quality left reduces accumulated issues exponentially later. Delaying never saves time.
Master Fundamentals First
Crawl through unit, integration and user workflow testing before trying exotic methods.
Rightsize Automation Investments
Balance automated functional testing with exploratory manual spot checks.
Safeguard Existing Value
Automate regression testing around key customer functionality first.
Confirm Software Works for Real People on Real Devices
Leverage real device cloud testing to efficiently validate broad compatibility.
As technology permeates society, software quality correlates directly with business sustainability. Testing strategically serves as insurance protecting organizations against the soaring costs of failure.
Now you have insider expertise to help position your teams for quality and innovation success in the face of increasing complexity!
