snapraid/beta/design.html

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                SnapRAID
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                    <li><a href="index" >Home</a></li>
                    <li><a href="ui" >UI & Daemon</a></li>
                    <li><a href="howitworks" >How it Works</a></li>
                    <li><a href="design" class="active">Design</a></li>
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            <h1 style="margin-bottom: 1rem;">Design Philosophy</h1>
            <blockquote style="font-size: 1.5rem; color: var(--text-accent); font-style: italic; margin: 0; padding: 0; border: none; font-family: serif;">
                Simplicity is prerequisite for reliability
            </blockquote>
            <cite style="display: block; margin-top: 1rem; font-size: 1rem; color: var(--text-secondary); font-style: normal;">
                <a href="http://en.wikipedia.org/wiki/Edsger_W._Dijkstra" style="color: var(--text-secondary); text-decoration: underline;">Edsger W. Dijkstra</a>
            </cite>
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                <strong style="color: var(--text-primary);">SnapRAID</strong> was created following the <a href="http://en.wikipedia.org/wiki/Unix_philosophy">Unix philosophy</a>:
                <em>Write programs that do one thing and do it well</em>.
            </p>
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                <h3>Reliability</h3>
            <p>
                The first design principle was <strong style="color: var(--text-primary);">reliability</strong>.
                The result is a simple architecture and an easy to understand implementation.
            </p>
                <p>
                    Extensive and automated tests with the runtime checker <a href="http://valgrind.org/">Valgrind</a>
                    and with the <a href="https://github.com/google/sanitizers">Google Sanitizers</a>
                    are done to ensure the correctness of the final application.
                    The test has a <a href="/cov/">code coverage of over 90%</a>, measured with <a href="https://github.com/linux-test-project/lcov">lcov</a>.
                </p>
                <p>
                    SnapRAID is also verified with Coverity Scan for both the
                    <a href="https://scan.coverity.com/projects/snapraid">CLI</a> and the <a href="https://scan.coverity.com/projects/snapraid-daemon">Daemon</a>.
                    and <a href="http://clang-analyzer.llvm.org/">clang</a> static analyzers,
                    and with the <a href="http://lcamtuf.coredump.cx/afl/">American Fuzzy Lop</a> fuzzy tester.
                </p>
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                <h3>Robustness</h3>
                <p>
                    The second design principle was <strong style="color: var(--text-primary);">robustness</strong>.
                    It supports any kind of problem. Even on kernel panics, power-downs
                    or any other hard failure at runtime, your redundancy data is in safe hands.
                </p>
                <p>
                    It uses all the possible storage techniques to ensure to always keep consistent
                    redundancy even after critical interruptions.
                </p>
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                <h3>Efficiency</h3>
                <p>
                    The third design principle was <strong style="color: var(--text-primary);">efficiency</strong>.
                    It's a native C application highly optimized to ensure maximum throughput of your disk array.
                </p>
                <p>
                    Integrity checks use the highly efficient <a href="https://github.com/aappleby/smhasher">murmur3</a>
                    and <a href="https://burtleburtle.net/bob/hash/spooky.html">SpookyHash</a> hashes at 128 bits.
                </p>
                <p>
                    Redundancy computations use a custom <a href="https://github.com/amadvance/snapraid/tree/master/raid">RAID library</a>
                    (based on Linux Kernel RAID) supporting up to six parity levels.
                    Internal structures use <a href="https://www.tommyds.it/">TommyDS</a>.
                </p>
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                <h3>Use of Artificial Intelligence</h3>
                <p>
                    This project <strong style="color: var(--text-primary);">is not "vibe-coded"</strong>.
                    Artificial intelligence is used strictly as a
                    precision tool and a pair programmer, never as a substitute for engineering judgment. All architecture
                    decisions, core logic, and safety guarantees remain under direct human control and review.
                </p>
                <p>
                    AI was used selectively to accelerate front-end scaffolding, component layout, and alignment with modern UI
                    standards. All functional behavior, state management, API integration, and system logic were implemented and
                    <strong style="color: var(--text-primary);">manually validated</strong>.
                </p>
                <p>
                    Development follows a <strong style="color: var(--text-primary);">human-led</strong>, AI-assisted workflow. The developer defines the architecture and writes
                    the core implementations. AI contributes by exploring design alternatives, surfacing edge cases, suggesting
                    optimizations, and helping refine documentation. Any generated output is reviewed, revised where necessary,
                    and hardened before integration.
                </p>
                <p>
                    This approach improves development efficiency while preserving strict <strong style="color: var(--text-primary);">engineering oversight</strong> and reliability.
                </p>
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                <h3>SnapRAID</h3>
                <p>Copyright &copy; 2026 Andrea Mazzoleni</p>
                <p class="license">Distributed under GPL v3 License</p>
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                <h4>Community</h4>
                <ul>
                    <li><a href="https://www.reddit.com/r/Snapraid/">Reddit r/snapraid</a></li>
                    <li><a href="https://sourceforge.net/p/snapraid/discussion/1677233/">SourceForge Forum</a></li>
                    <li><a href="https://github.com/amadvance/snapraid/">GitHub SnapRAID CLI</a></li>
                    <li><a href="https://github.com/amadvance/snapraid-daemon/">GitHub SnapRAID Daemon</a></li>
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