Daily micro-tips for C#, SQL, performance, and scalable backend engineering.
📝 JSON, SQL, HTML in Your Code — Without Escaping Escaping quotes in strings is painful. Raw string literals (C# 11) allow any quotes, any whitespace. Copy-paste JSON directly! ❌ Old Way (Escaping Hell) string json = “{\n \”name\”: \”Alice\”,\n \”age\”: 30\n}”; ✅ Raw String Literal string json = “”” { “name”: “Alice”, “age”: 30 […]
✅ No More Null Reference Warnings NonNullable properties should never be null. But how to enforce? required keyword makes initialization mandatory at compile time. ❌ Before (Runtime Null) public class User { public string Name { get; set; } // Can be null! } var user = new User(); // Name = null user.Name.Length; […]
🔄 Lateral Joins = Subquery That Can Reference Outer Table Normal subqueries run independently. LATERAL subquery runs for each row, can reference columns from outer query. 📝 Without LATERAL (Limited) — Can’t reference outer user_id SELECT u.name, ( SELECT order_date FROM orders WHERE user_id = u.id ORDER BY order_date DESC LIMIT 1 ) as last_order […]
🛡️ Prevent DDoS and Brute Force Rate limiting stops attackers (and misbehaving clients). .NET 7+ has built-in rate limiting. No external libraries needed. 📝 Setup Rate Limiting // Program.cs builder.Services.AddRateLimiter(options => { // Global rate limit options.GlobalLimiter = PartitionedRateLimiter.Create( httpContext => RateLimitPartition.GetFixedWindowLimiter( partitionKey: httpContext.User.Identity?.Name ?? httpContext.Request.Headers.Host.ToString(), factory: partition => new FixedWindowRateLimiterOptions { AutoReplenishment = true, […]
🔥 Committed Secrets? Erase from History .env file committed. Now in Git history forever. git filter-branch rewrites history. Remove sensitive files completely. 🔧 Remove File from History # Backup your repository first! git clone –mirror your-repo repo-backup # Remove .env file from entire history git filter-branch –force –index-filter \ ‘git rm –cached –ignore-unmatch .env’ \ […]
🗜️ Compress Data Before Sending Send huge JSON? Compress it first. Compression Streams API compresses in browser before upload. Save bandwidth, faster uploads. 📝 Compress and Send async function sendCompressed(data) { // Convert to JSON string const jsonString = JSON.stringify(data); // Compress with GZIP const compressedStream = new Blob([jsonString]) .stream() .pipeThrough(new CompressionStream(‘gzip’)); // Send compressed […]
📅 Finally, a Good Date API Date object is broken (months are 0-indexed, mutates, timezone issues). Temporal fixes everything. Immutable, timezone-aware, intuitive. 📝 Temporal Basics // Current date/time const now = Temporal.Now.zonedDateTimeISO(); // with timezone const today = Temporal.Now.plainDateISO(); // date only const time = Temporal.Now.plainTimeISO(); // time only // Create dates (months are 1-indexed!) […]
💬 No More JavaScript for Tooltips Popover API creates native popups, tooltips, and menus. Light dismiss (click outside closes), top layer, accessible. No more Tippy.js or Popper. 📝 Basic Popover <button popovertarget=”my-popover”>Toggle Popover</button> <div id=”my-popover” popover> <h3>Popover Title</h3> <p>This is a native popover! Click outside to close.</p> <button popovertarget=”my-popover” popovertargetaction=”hide”>Close</button> </div> <!– Manual popover –> […]
🎨 Color Manipulation Without Preprocessors Sass had lighten(), darken(), mix(). CSS now has color-mix(), relative colors, and OKLCH. Native color functions! 🎨 color-mix() /* Mix two colors */ .hover-effect { background-color: color-mix(in srgb, blue 30%, red); } .brand-gradient { background: color-mix(in oklch, var(–primary) 50%, white); } /* Mix with transparency */ .transparent-blue { background: color-mix(in […]
🎮 Stop Background Processes from Stealing FPS Windows Update, antivirus scans, OneDrive sync — all kill gaming performance. Game Mode prioritizes your game, pauses background tasks. 🔧 Enable Game Mode Settings → Gaming → Game Mode → On Win + G → Game Bar (check if Game Mode active) Per-game settings: Settings → Gaming → […]
📝 Never Write Meeting Notes Again Hours of meeting recordings. Who said what? What was decided? AI turns transcripts into actionable summaries. 📝 The Prompt Generate a concise meeting summary from this transcript: [Paste meeting transcript here] Include: 1. One-sentence overview of the meeting purpose 2. Key decisions made (bullet points) 3. Action items with […]
🛡️ Is Your Image Safe? Base images have known vulnerabilities. Docker Scout scans images for CVEs. Shows severity, fix versions, and remediation steps. 🔧 Scan Image # Install Docker Scout (Docker Desktop includes it) docker scout –help # Scan local image docker scout quick myapp:latest # Scan with detailed output docker scout cves myapp:latest # […]
📈 HPA Scales Pods. VPA Scales Pod Resources. Guessing CPU/memory requests is hard. Vertical Pod Autoscaler recommends or automatically adjusts resource requests based on actual usage. 📝 Install VPA git clone https://github.com/kubernetes/autoscaler.git cd autoscaler/vertical-pod-autoscaler ./hack/vpa-up.sh kubectl get pods -n kube-system | grep vpa 🎯 VPA Configuration apiVersion: autoscaling.k8s.io/v1 kind: VerticalPodAutoscaler metadata: name: myapp-vpa spec: targetRef: […]
⚡ Don’t Let WP_Query Kill Your Database WP_Query is powerful but dangerous. Bad queries = slow site. Learn best practices for performance. 📝 Do’s and Don’ts // ❌ DON’T: Query inside loop while (have_posts()) { the_post(); $related = new WP_Query([‘post_type’ => ‘post’, ‘posts_per_page’ => 5]); // Runs 10 times = 10 extra queries! } // […]
🏢 Put a Picture on a Building That Matches Perspective Normal clone stamp doesn’t understand perspective. Vanishing Point lets you paint, clone, and paste in perspective. Perfect for billboards, walls, floors. 📝 How to Use 1. Filter → Vanishing Point (Ctrl+Alt+V) 2. Click to create plane (4 points) 3. Adjust grid (blue lines should match […]
🔍 Find Any File, Type, Member, Symbol Solution Explorer is slow. Ctrl + , (Navigate To) searches everything: files, classes, methods, properties. Type a few letters, press Enter. ⌨️ How to Use Ctrl + , → Open search box Type “OrderService” → Shows matching files, classes, methods ↓ ↑ arrows → Navigate results Enter → […]
📁 Every File Starts with namespace Something { } That’s an extra indentation for no reason. File-scoped namespaces remove the braces. Less code, less indentation. ❌ Old Style namespace MyApp.Services { public class OrderService { public void Process() { // Code indented 3 levels already } } } ✅ File-Scoped namespace MyApp.Services; public class OrderService […]
✨ More Than Just ${variable} String interpolation can format numbers, align text, use expressions, and even span multiple lines. Level up your strings. 📝 Formatting Numbers double price = 1234.5678; string formatted = $”Price: {price:C2}”; // $1,234.57 formatted = $”Percent: {0.1234:P1}”; // 12.3% formatted = $”{price:N0}”; // 1,235 formatted = $”{price:F2}”; // 1234.57 formatted = […]
📝 Name Your Subqueries Subqueries inside subqueries are unreadable. CTEs (WITH clause) give subqueries names. Your future self will thank you. 📝 Without CTE (Unreadable) SELECT name, total_orders FROM ( SELECT u.name, COUNT(o.id) as total_orders FROM users u JOIN orders o ON u.id = o.user_id WHERE o.status = ‘completed’ GROUP BY u.id, u.name ) order_stats […]
❤️ Is Your App Really Healthy? App running but database down? Cache not responding? Health checks test dependencies. Perfect for load balancer readiness probes. 📝 Basic Setup // Program.cs builder.Services.AddHealthChecks() .AddDbContextCheck() .AddUrlGroup(new Uri(“https://api.example.com”)) var app = builder.Build(); app.MapHealthChecks(“/health/ready”, new HealthCheckOptions { Predicate = _ => true, ResponseWriter = UIResponseWriter.WriteHealthCheckUIResponse }); app.MapHealthChecks(“/health/live”, new HealthCheckOptions { Predicate […]
⚙️ Run Scripts Automatically on Git Events Run tests before commit? Lint before push? Format code? Git hooks automate anything. No more forgotten steps. 📝 Available Hooks .git/hooks/ (create executable files) Client-side: – pre-commit # Run tests before commit (cancel if fails) – prepare-commit-msg # Edit commit message before editor opens – commit-msg # Validate […]
🌐 “No ‘Access-Control-Allow-Origin’” — The Most Hated Error CORS blocks requests from different origins. Fix it on the server, not on the client. Here’s how. 📝 Server Fixes // Node.js (Express) app.use((req, res, next) => { res.header(‘Access-Control-Allow-Origin’, ‘*’); // Allow all (not for prod) res.header(‘Access-Control-Allow-Methods’, ‘GET, POST, PUT, DELETE’); res.header(‘Access-Control-Allow-Headers’, ‘Content-Type, Authorization’); res.header(‘Access-Control-Allow-Credentials’, ‘true’); if […]
🧵 Multiple Threads, One Memory Web Workers communicate via message passing. SharedArrayBuffer + Atomics enables shared memory. No copying. True multithreading. 📝 Basic Shared Memory // Main thread const sharedBuffer = new SharedArrayBuffer(Int32Array.BYTES_PER_ELEMENT * 2); const sharedArray = new Int32Array(sharedBuffer); sharedArray[0] = 0; // Counter const worker = new Worker(‘worker.js’); worker.postMessage(sharedBuffer); // Transfer, not copy! […]
📱 Number Field Shows Number Keyboard type=’number’ has spinner buttons. type=’tel’ shows number keyboard but no spinner. inputmode controls keyboard without changing validation. 📝 Input Mode Values <!– Numeric keyboard (no spinner) –> <input type=’text’ inputmode=’numeric’ placeholder=’Age’> <!– Decimal keyboard (with dot) –> <input type=’text’ inputmode=’decimal’ placeholder=’Price’> <!– Email keyboard (@ and .com) –> <input […]
🎨 One Line, Beautiful Checkboxes Customizing checkboxes used to require JavaScript or CSS hacks. accent-color changes their color in one line. 📝 Basic Usage /* Apply to all form controls */ body { accent-color: #3498db; } /* Specific controls */ input[type=’checkbox’] { accent-color: #2ecc71; } input[type=’radio’] { accent-color: #e74c3c; } input[type=’range’] { accent-color: #f39c12; } […]
🧪 Random Crashes? Test Your RAM PC freezing? Blue screens? Windows Memory Diagnostic tests RAM for errors. Find faulty memory before buying new parts. 🔧 How to Run Method 1: Start → Windows Memory Diagnostic Method 2: Win + R → mdsched.exe Method 3: Control Panel → Administrative Tools → Windows Memory Diagnostic Choose: – […]
🔍 Regular Expressions Are Hard. AI Makes Them Easy. Need to extract emails? Phone numbers? Dates? AI generates regex from examples. No more regex debugging hell. 📝 The Prompt Generate a regular expression that matches: [Provide examples of what you want to match] Example inputs that SHOULD match: – [example 1] – [example 2] – […]
🚫 .git folder in Docker Image? No! Docker sends entire folder to daemon. .dockerignore excludes unnecessary files. Faster builds, smaller images, less clutter. 📝 .dockerignore Example # Git .git/ .gitignore # Node node_modules/ npm-debug.log # .NET bin/ obj/ *.user *.suo # Tests test/ __tests__/ coverage/ # Logs *.log logs/ # Environment .env .env.local .env.*.local # […]
👯 Keep Related Pods Close (or Far Apart) Cache and app should be on same node. Database replicas should be on different nodes. Pod affinity/anti-affinity controls pod placement. 📝 Pod Affinity (Same Node) apiVersion: v1 kind: Pod metadata: name: web-app spec: affinity: podAffinity: requiredDuringSchedulingIgnoredDuringExecution: – labelSelector: matchLabels: app: cache topologyKey: kubernetes.io/hostname containers: – name: app […]
💾 WP_Query Too Slow? Go Direct! WP_Query is convenient but slow for complex reports. $wpdb runs raw SQL. Faster, more powerful, full control. 📝 Basic $wpdb global $wpdb; // Get single value $user_count = $wpdb->get_var(“SELECT COUNT(*) FROM {$wpdb->users}”); // Get single row $user = $wpdb->get_row(“SELECT * FROM {$wpdb->users} WHERE ID = 123”); // Get all […]