Design Patterns

<h2 id="design-patterns" class="position-relative d-flex align-items-center group"> Design Patterns <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="design-patterns" aria-haspopup="dialog" aria-label="Share link: Design Patterns"> Share link </button> </h2><div id="headingShareModal" class="heading-share-modal" role="dialog" aria-modal="true" aria-labelledby="headingShareTitle" hidden> <div class="hsm-dialog" role="document"> <div class="hsm-header"> <h2 id="headingShareTitle" class="h6 mb-0 fw-bold">Share this section</h2> <button type="button" class="hsm-close" aria-label="Close"> </button> </div> <div class="hsm-body"> <label for="headingShareInput" class="form-label small text-muted mb-1 text-uppercase fw-bold" style="font-size: 0.7rem; letter-spacing: 0.5px;">Permalink</label> <div class="input-group mb-4 hsm-url-group"> <input id="headingShareInput" type="text" class="form-control font-monospace" readonly aria-readonly="true" style="font-size: 0.85rem;" /> <button class="btn btn-primary hsm-copy" type="button" aria-label="Copy" title="Copy"> </button> </div> <div class="small fw-bold mb-2 text-muted text-uppercase" style="font-size: 0.7rem; 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Geode leverages proven design patterns to create maintainable, scalable, and testable code across its graph database implementation. <h3 id="creational-patterns" class="position-relative d-flex align-items-center group"> Creational Patterns <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="creational-patterns" aria-haspopup="dialog" aria-label="Share link: Creational Patterns"> Share link </button> </h3> <h4 id="factory-pattern" class="position-relative d-flex align-items-center group"> Factory Pattern <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="factory-pattern" aria-haspopup="dialog" aria-label="Share link: Factory Pattern"> Share link </button> </h4>Geode uses factories to create complex objects with consistent initialization: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">pub const NodeFactory = struct { allocator: Allocator, pub fn createNode(self: *Self, labels: []const []const u8, props: Properties) !*Node { const node = try self.allocator.create(Node); errdefer self.allocator.destroy(node); node.* = Node{ .id = try generateId(), .labels = try self.allocator.dupe([]const u8, labels), .properties = try props.clone(self.allocator), }; return node; } }; </code></pre></div>This pattern centralizes object creation logic and ensures proper initialization. <h4 id="builder-pattern" class="position-relative d-flex align-items-center group"> Builder Pattern <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="builder-pattern" aria-haspopup="dialog" aria-label="Share link: Builder Pattern"> Share link </button> </h4>Complex query construction uses the builder pattern: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Fluent query builder pattern in GQL MATCH (p:Person) WHERE p.age > 18 WITH p, p.followers AS followers WHERE SIZE(followers) > 1000 RETURN p.name, SIZE(followers) AS follower_count ORDER BY follower_count DESC LIMIT 10; </code></pre></div>Builders enable step-by-step construction of complex objects. <h4 id="singleton-pattern" class="position-relative d-flex align-items-center group"> Singleton Pattern <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="singleton-pattern" aria-haspopup="dialog" aria-label="Share link: Singleton Pattern"> Share link </button> </h4>Geode uses singletons for global system resources: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">pub const ConfigManager = struct { var instance: ?*ConfigManager = null; var mutex: std.Thread.Mutex = .{}; pub fn getInstance(allocator: Allocator) !*ConfigManager { mutex.lock(); defer mutex.unlock(); if (instance == null) { instance = try allocator.create(ConfigManager); instance.?.* = try ConfigManager.init(allocator); } return instance.?; } }; </code></pre></div>Singletons ensure a single instance of critical resources. <h4 id="object-pool-pattern" class="position-relative d-flex align-items-center group"> Object Pool Pattern <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="object-pool-pattern" aria-haspopup="dialog" aria-label="Share link: Object Pool Pattern"> Share link </button> </h4>Connection pooling reuses expensive resources: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">pub const ConnectionPool = struct { available: std.ArrayList(*Connection), in_use: std.ArrayList(*Connection), max_size: usize, pub fn acquire(self: *Self) !*Connection { if (self.available.items.len > 0) { const conn = self.available.pop(); try self.in_use.append(conn); return conn; } if (self.getTotalSize() < self.max_size) { const conn = try self.createConnection(); try self.in_use.append(conn); return conn; } return error.PoolExhausted; } }; </code></pre></div>Pooling reduces allocation overhead for frequently used objects. <h3 id="structural-patterns" class="position-relative d-flex align-items-center group"> Structural Patterns <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="structural-patterns" aria-haspopup="dialog" aria-label="Share link: Structural Patterns"> Share link </button> </h3> <h4 id="adapter-pattern" class="position-relative d-flex align-items-center group"> Adapter Pattern <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="adapter-pattern" aria-haspopup="dialog" aria-label="Share link: Adapter Pattern"> Share link </button> </h4>Geode adapts different storage backends to a common interface: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">pub const StorageAdapter = struct { pub const Interface = struct { ptr: *anyopaque, vtable: *const VTable, pub const VTable = struct { read: *const fn(*anyopaque, []const u8) anyerror![]u8, write: *const fn(*anyopaque, []const u8, []const u8) anyerror!void, delete: *const fn(*anyopaque, []const u8) anyerror!void, }; pub fn read(self: Interface, key: []const u8) ![]u8 { return self.vtable.read(self.ptr, key); } }; }; </code></pre></div>Adapters enable interchangeable implementations. <h4 id="decorator-pattern" class="position-relative d-flex align-items-center group"> Decorator Pattern <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="decorator-pattern" aria-haspopup="dialog" aria-label="Share link: Decorator Pattern"> Share link </button> </h4>Query execution is enhanced through decorators: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">pub const QueryExecutor = struct { base: *const Executor, pub const CachingDecorator = struct { executor: QueryExecutor, cache: *QueryCache, pub fn execute(self: *Self, query: Query) !Result { if (self.cache.get(query.hash())) |cached| { return cached; } const result = try self.executor.base.execute(query); try self.cache.put(query.hash(), result); return result; } }; }; </code></pre></div>Decorators add behavior without modifying existing code. <h4 id="facade-pattern" class="position-relative d-flex align-items-center group"> Facade Pattern <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="facade-pattern" aria-haspopup="dialog" aria-label="Share link: Facade Pattern"> Share link </button> </h4>Complex subsystems are simplified through facades: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">pub const GraphDatabaseFacade = struct { storage: *StorageEngine, query_engine: *QueryEngine, tx_manager: *TransactionManager, pub fn executeQuery(self: *Self, gql: []const u8) !ResultSet { const tx = try self.tx_manager.begin(); errdefer tx.rollback() catch {}; const ast = try self.query_engine.parse(gql); const plan = try self.query_engine.optimize(ast); const result = try self.query_engine.execute(plan, self.storage); try tx.commit(); return result; } }; </code></pre></div>Facades provide a simplified interface to complex systems. <h4 id="proxy-pattern" class="position-relative d-flex align-items-center group"> Proxy Pattern <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="proxy-pattern" aria-haspopup="dialog" aria-label="Share link: Proxy Pattern"> Share link </button> </h4>Remote access and caching use proxy patterns: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">pub const RemoteGraphProxy = struct { client: *QuicClient, local_cache: *Cache, pub fn getNode(self: *Self, id: NodeId) !Node { // Check local cache first if (self.local_cache.get(id)) |node| { return node; } // Fetch from remote server const node = try self.client.fetchNode(id); try self.local_cache.put(id, node); return node; } }; </code></pre></div>Proxies control access and add functionality transparently. <h4 id="composite-pattern" class="position-relative d-flex align-items-center group"> Composite Pattern <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="composite-pattern" aria-haspopup="dialog" aria-label="Share link: Composite Pattern"> Share link </button> </h4>Graph structures use the composite pattern: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">pub const GraphElement = union(enum) { node: Node, edge: Edge, subgraph: Subgraph, pub fn properties(self: GraphElement) Properties { return switch (self) { .node => |n| n.properties, .edge => |e| e.properties, .subgraph => |s| s.aggregateProperties(), }; } }; </code></pre></div>Composites treat individual objects and compositions uniformly. <h3 id="behavioral-patterns" class="position-relative d-flex align-items-center group"> Behavioral Patterns <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="behavioral-patterns" aria-haspopup="dialog" aria-label="Share link: Behavioral Patterns"> Share link </button> </h3> <h4 id="strategy-pattern" class="position-relative d-flex align-items-center group"> Strategy Pattern <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="strategy-pattern" aria-haspopup="dialog" aria-label="Share link: Strategy Pattern"> Share link </button> </h4>Query optimization uses pluggable strategies: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">pub const OptimizationStrategy = union(enum) { rule_based: RuleBasedOptimizer, cost_based: CostBasedOptimizer, heuristic: HeuristicOptimizer, pub fn optimize(self: OptimizationStrategy, plan: QueryPlan) !QueryPlan { return switch (self) { .rule_based => |opt| opt.optimize(plan), .cost_based => |opt| opt.optimize(plan), .heuristic => |opt| opt.optimize(plan), }; } }; </code></pre></div>Strategies enable runtime algorithm selection. <h4 id="observer-pattern" class="position-relative d-flex align-items-center group"> Observer Pattern <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="observer-pattern" aria-haspopup="dialog" aria-label="Share link: Observer Pattern"> Share link </button> </h4>Change notifications use the observer pattern: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">pub const ChangeNotifier = struct { observers: std.ArrayList(*Observer), pub fn attach(self: *Self, observer: *Observer) !void { try self.observers.append(observer); } pub fn notify(self: *Self, event: ChangeEvent) !void { for (self.observers.items) |observer| { try observer.update(event); } } }; </code></pre></div>Observers decouple event sources from event handlers. <h4 id="iterator-pattern" class="position-relative d-flex align-items-center group"> Iterator Pattern <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="iterator-pattern" aria-haspopup="dialog" aria-label="Share link: Iterator Pattern"> Share link </button> </h4>Result sets provide consistent iteration: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">pub const ResultIterator = struct { result_set: *ResultSet, position: usize, pub fn next(self: *Self) ?Row { if (self.position >= self.result_set.rows.len) { return null; } defer self.position += 1; return self.result_set.rows[self.position]; } }; </code></pre></div>Iterators provide sequential access without exposing internal structure. <h4 id="command-pattern" class="position-relative d-flex align-items-center group"> Command Pattern <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="command-pattern" aria-haspopup="dialog" aria-label="Share link: Command Pattern"> Share link </button> </h4>Transactions use the command pattern: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">pub const Command = union(enum) { insert_node: InsertNodeCommand, update_node: UpdateNodeCommand, delete_node: DeleteNodeCommand, pub fn execute(self: Command, storage: *Storage) !void { switch (self) { .insert_node => |cmd| try storage.insertNode(cmd.node), .update_node => |cmd| try storage.updateNode(cmd.id, cmd.properties), .delete_node => |cmd| try storage.deleteNode(cmd.id), } } pub fn undo(self: Command, storage: *Storage) !void { switch (self) { .insert_node => |cmd| try storage.deleteNode(cmd.node.id), .update_node => |cmd| try storage.updateNode(cmd.id, cmd.old_properties), .delete_node => |cmd| try storage.insertNode(cmd.deleted_node), } } }; </code></pre></div>Commands encapsulate operations for execution, undo, and replay. <h4 id="template-method-pattern" class="position-relative d-flex align-items-center group"> Template Method Pattern <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="template-method-pattern" aria-haspopup="dialog" aria-label="Share link: Template Method Pattern"> Share link </button> </h4>Query execution follows a template: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">pub const QueryExecutionTemplate = struct { pub fn execute(self: *Self, query: Query) !Result { try self.validate(query); const plan = try self.plan(query); const optimized = try self.optimize(plan); const result = try self.executePhysical(optimized); try self.postProcess(result); return result; } // Subclasses override specific steps fn validate(self: *Self, query: Query) !void; fn plan(self: *Self, query: Query) !QueryPlan; fn optimize(self: *Self, plan: QueryPlan) !QueryPlan; }; </code></pre></div>Templates define algorithm structure with customizable steps. <h4 id="chain-of-responsibility-pattern" class="position-relative d-flex align-items-center group"> Chain of Responsibility Pattern <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="chain-of-responsibility-pattern" aria-haspopup="dialog" aria-label="Share link: Chain of Responsibility Pattern"> Share link </button> </h4>Request processing uses handler chains: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">pub const RequestHandler = struct { next: ?*RequestHandler, pub fn handle(self: *Self, request: Request) !Response { if (self.canHandle(request)) { return self.process(request); } if (self.next) |next_handler| { return next_handler.handle(request); } return error.NoHandlerFound; } fn canHandle(self: *Self, request: Request) bool; fn process(self: *Self, request: Request) !Response; }; </code></pre></div>Chains enable flexible request routing and processing. <h4 id="state-pattern" class="position-relative d-flex align-items-center group"> State Pattern <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="state-pattern" aria-haspopup="dialog" aria-label="Share link: State Pattern"> Share link </button> </h4>Connection lifecycle management uses state machines: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">pub const ConnectionState = union(enum) { disconnected: Disconnected, connecting: Connecting, connected: Connected, closing: Closing, pub fn handleEvent(self: *ConnectionState, event: Event) !void { switch (self.*) { .disconnected => |*state| self.* = try state.connect(), .connecting => |*state| self.* = try state.onConnected(), .connected => |*state| self.* = try state.onClose(), .closing => |*state| self.* = try state.onClosed(), } } }; </code></pre></div>State patterns make state transitions explicit and manageable. <h3 id="solid-principles" class="position-relative d-flex align-items-center group"> SOLID Principles <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="solid-principles" aria-haspopup="dialog" aria-label="Share link: SOLID Principles"> Share link </button> </h3> <h4 id="single-responsibility-principle" class="position-relative d-flex align-items-center group"> Single Responsibility Principle <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="single-responsibility-principle" aria-haspopup="dialog" aria-label="Share link: Single Responsibility Principle"> Share link </button> </h4>Each component has one reason to change: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">// Good - Single responsibility pub const UserValidator = struct { pub fn validate(user: User) !void { } }; pub const UserRepository = struct { pub fn save(user: User) !void { } }; pub const UserNotifier = struct { pub fn sendWelcomeEmail(user: User) !void { } }; </code></pre></div> <h4 id="open-closed-principle" class="position-relative d-flex align-items-center group"> Open-Closed Principle <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="open-closed-principle" aria-haspopup="dialog" aria-label="Share link: Open-Closed Principle"> Share link </button> </h4>Open for extension, closed for modification: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">// Good - Extensible through interfaces pub const Serializer = struct { pub const Interface = struct { serialize: *const fn(*anyopaque, *Node) anyerror![]u8, }; }; // Add new serializers without modifying existing code pub const JsonSerializer = struct { /* implementation */ }; pub const BinarySerializer = struct { /* implementation */ }; </code></pre></div> <h4 id="liskov-substitution-principle" class="position-relative d-flex align-items-center group"> Liskov Substitution Principle <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="liskov-substitution-principle" aria-haspopup="dialog" aria-label="Share link: Liskov Substitution Principle"> Share link </button> </h4>Subtypes must be substitutable for their base types: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">// All storage implementations must satisfy the contract pub const Storage = struct { pub const Interface = struct { // Contract: read returns data or error read: *const fn(*anyopaque, []const u8) anyerror![]u8, // Contract: write persists data or returns error write: *const fn(*anyopaque, []const u8, []const u8) anyerror!void, }; }; </code></pre></div> <h4 id="interface-segregation-principle" class="position-relative d-flex align-items-center group"> Interface Segregation Principle <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="interface-segregation-principle" aria-haspopup="dialog" aria-label="Share link: Interface Segregation Principle"> Share link </button> </h4>Clients shouldn’t depend on unused interfaces: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">// Good - Split into specific interfaces pub const Readable = struct { read: *const fn(*anyopaque, []const u8) anyerror![]u8, }; pub const Writable = struct { write: *const fn(*anyopaque, []const u8, []const u8) anyerror!void, }; // Clients only depend on what they need pub const LogReader = struct { storage: Readable, // Only needs read capability }; </code></pre></div> <h4 id="dependency-inversion-principle" class="position-relative d-flex align-items-center group"> Dependency Inversion Principle <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="dependency-inversion-principle" aria-haspopup="dialog" aria-label="Share link: Dependency Inversion Principle"> Share link </button> </h4>Depend on abstractions, not concretions: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">// Good - Depends on interface pub const QueryEngine = struct { storage: StorageInterface, // Abstract interface pub fn execute(self: *Self, query: Query) !Result { return self.storage.fetch(query.pattern); } }; </code></pre></div> <h3 id="best-practices" class="position-relative d-flex align-items-center group"> Best Practices <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="best-practices" aria-haspopup="dialog" aria-label="Share link: Best Practices"> Share link </button> </h3> <h4 id="pattern-selection" class="position-relative d-flex align-items-center group"> Pattern Selection <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="pattern-selection" aria-haspopup="dialog" aria-label="Share link: Pattern Selection"> Share link </button> </h4>Choose patterns based on actual needs: <ul> <li>Use patterns to solve real problems, not for their own sake</li> <li>Start simple, refactor to patterns when complexity warrants</li> <li>Consider team familiarity and maintenance implications</li> </ul> <h4 id="pattern-composition" class="position-relative d-flex align-items-center group"> Pattern Composition <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="pattern-composition" aria-haspopup="dialog" aria-label="Share link: Pattern Composition"> Share link </button> </h4>Combine patterns for complex scenarios: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">// Strategy + Factory + Singleton pub const OptimizerFactory = struct { var instance: ?*OptimizerFactory = null; pub fn getInstance() !*OptimizerFactory { /* ... */ } pub fn createOptimizer(strategy: OptimizationType) !*Optimizer { return switch (strategy) { .rule_based => try RuleBasedOptimizer.init(), .cost_based => try CostBasedOptimizer.init(), }; } }; </code></pre></div> <h4 id="anti-patterns-to-avoid" class="position-relative d-flex align-items-center group"> Anti-Patterns to Avoid <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="anti-patterns-to-avoid" aria-haspopup="dialog" aria-label="Share link: Anti-Patterns to Avoid"> Share link </button> </h4>Common mistakes to watch for: God Object - Classes that know or do too much Spaghetti Code - Lack of structure and organization Golden Hammer - Using one pattern for everything Premature Optimization - Optimizing before measuring <h3 id="performance-considerations" class="position-relative d-flex align-items-center group"> Performance Considerations <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="performance-considerations" aria-haspopup="dialog" aria-label="Share link: Performance Considerations"> Share link </button> </h3> <h4 id="pattern-overhead" class="position-relative d-flex align-items-center group"> Pattern Overhead <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="pattern-overhead" aria-haspopup="dialog" aria-label="Share link: Pattern Overhead"> Share link </button> </h4>Some patterns add indirection: <ul> <li>Virtual function calls have small overhead</li> <li>Extra allocations impact memory usage</li> <li>Balance abstraction with performance needs</li> </ul> <h4 id="optimization-opportunities" class="position-relative d-flex align-items-center group"> Optimization Opportunities <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="optimization-opportunities" aria-haspopup="dialog" aria-label="Share link: Optimization Opportunities"> Share link </button> </h4>Patterns can enable optimizations: <ul> <li>Strategy pattern allows runtime algorithm selection</li> <li>Proxy pattern enables transparent caching</li> <li>Flyweight pattern reduces memory usage</li> </ul> <h3 id="testing-patterns" class="position-relative d-flex align-items-center group"> Testing Patterns <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="testing-patterns" aria-haspopup="dialog" aria-label="Share link: Testing Patterns"> Share link </button> </h3> <h4 id="test-doubles" class="position-relative d-flex align-items-center group"> Test Doubles <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="test-doubles" aria-haspopup="dialog" aria-label="Share link: Test Doubles"> Share link </button> </h4>Use test patterns for isolation: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">pub const MockStorage = struct { expected_calls: std.ArrayList(Call), pub fn read(self: *Self, key: []const u8) ![]u8 { try self.recordCall(.{ .read = key }); return self.canned_response; } }; </code></pre></div> <h4 id="builder-pattern-for-tests" class="position-relative d-flex align-items-center group"> Builder Pattern for Tests <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="builder-pattern-for-tests" aria-haspopup="dialog" aria-label="Share link: Builder Pattern for Tests"> Share link </button> </h4>Simplify test data creation: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-zig" data-lang="zig">pub const NodeBuilder = struct { node: Node, pub fn withLabel(self: *Self, label: []const u8) *Self { try self.node.labels.append(label); return self; } pub fn withProperty(self: *Self, key: []const u8, value: Value) *Self { try self.node.properties.put(key, value); return self; } pub fn build(self: *Self) Node { return self.node; } }; </code></pre></div> <h3 id="related-topics" class="position-relative d-flex align-items-center group"> Related Topics <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="related-topics" aria-haspopup="dialog" aria-label="Share link: Related Topics"> Share link </button> </h3><ul> <li><a href="/tags/architecture" >Architecture</a> - System architecture patterns</li> <li><a href="/tags/best-practices" >Best Practices</a> - Development best practices</li> <li><a href="/tags/testing" >Testing</a> - Testing strategies and patterns</li> <li><a href="/tags/performance" >Performance</a> - Performance optimization</li> </ul> <h3 id="learn-more" class="position-relative d-flex align-items-center group"> Learn More <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="learn-more" aria-haspopup="dialog" aria-label="Share link: Learn More"> Share link </button> </h3><ul> <li><a href="https://en.wikipedia.org/wiki/Design_Patterns" aria-label="Design Patterns: Elements of Reusable Object-Oriented Software – opens in new window" target="_blank" rel="noopener noreferrer" >Design Patterns: Elements of Reusable Object-Oriented Software ↗ </a> </li> <li><a href="https://en.wikipedia.org/wiki/SOLID" aria-label="SOLID Principles – opens in new window" target="_blank" rel="noopener noreferrer" >SOLID Principles ↗ </a> </li> <li><a href="https://refactoring.guru/design-patterns" aria-label="Refactoring Guru - Design Patterns – opens in new window" target="_blank" rel="noopener noreferrer" >Refactoring Guru - Design Patterns ↗ </a> </li> </ul>

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