Muhammad Waseem

Muhammad WaseemAug 22, 2026

𝗖# 𝟭𝟰 𝗺𝗮𝗸𝗲𝘀 𝗮𝗿𝗿𝗮𝘆𝘀, 𝗦𝗽𝗮𝗻<𝗧>, 𝗮𝗻𝗱 𝗥𝗲𝗮𝗱𝗢𝗻𝗹𝘆𝗦𝗽𝗮𝗻<𝗧> 𝗰𝗼𝗻𝘃𝗲𝗿𝘁 𝗶𝗻𝘁𝗼 𝗲𝗮𝗰𝗵 𝗼𝘁𝗵𝗲𝗿 𝗮𝘂𝘁𝗼𝗺𝗮𝘁𝗶𝗰𝗮𝗹𝗹𝘆. Span<T> and ReadOnlySpan<T> are already everywhere in the runtime for performance without giving up safety. C# 14 gives the compiler first-class support for converting between them and T[]: 𝚟𝚘𝚒𝚍 𝙿𝚛𝚒𝚗𝚝𝙵𝚒𝚛𝚜𝚝(𝚁𝚎𝚊𝚍𝙾𝚗𝚕𝚢𝚂𝚙𝚊𝚗<𝚒𝚗𝚝> 𝚟𝚊𝚕𝚞𝚎𝚜) { 𝙲𝚘𝚗𝚜𝚘𝚕𝚎.𝚆𝚛𝚒𝚝𝚎𝙻𝚒𝚗𝚎(𝚟𝚊𝚕𝚞𝚎𝚜[𝟶]); } 𝚒𝚗𝚝[] 𝚗𝚞𝚖𝚋𝚎𝚛𝚜 = [𝟷𝟶, 𝟸𝟶, 𝟹𝟶]; 𝙿𝚛𝚒𝚗𝚝𝙵𝚒𝚛𝚜𝚝(𝚗𝚞𝚖𝚋𝚎𝚛𝚜); An int array flowing straight into a ReadOnlySpan<int> parameter, no conversion call in sight. ✔️ Conversions apply between ReadOnlySpan<T>, Span<T>, and T[] ✔️ Span types can now act as extension method receivers ✔️ Helps the compiler with generic type inference when arrays and spans are mixed together 📌 If you found it helpful, then you should join my weekly .NET newsletter with 10k+ engineers. Subscribe here → http://mwaseemzakir.com Repost ♻️ would be appreciated #csharp #dotnet #dotnetcore #csharp14 #performance

Muhammad WaseemAug 24, 2026

𝗖# 𝟭𝟰 𝗹𝗲𝘁𝘀 𝘆𝗼𝘂 𝗮𝗱𝗱 𝗿𝗲𝗳, 𝗼𝘂𝘁, 𝗼𝗿 𝗶𝗻 𝘁𝗼 𝗮 𝗹𝗮𝗺𝗯𝗱𝗮 𝗽𝗮𝗿𝗮𝗺𝗲𝘁𝗲𝗿 𝘄𝗶𝘁𝗵𝗼𝘂𝘁 𝘁𝘆𝗽𝗶𝗻𝗴 𝗶𝘁. Before C# 14, adding a modifier like out to a lambda parameter forced you to type every parameter: 𝚃𝚛𝚢𝙿𝚊𝚛𝚜𝚎<𝚒𝚗𝚝> 𝚙𝚊𝚛𝚜𝚎𝟸 = (𝚜𝚝𝚛𝚒𝚗𝚐 𝚝𝚎𝚡𝚝, 𝚘𝚞𝚝 𝚒𝚗𝚝 𝚛𝚎𝚜𝚞𝚕𝚝) => 𝙸𝚗𝚝𝟹𝟸.𝚃𝚛𝚢𝙿𝚊𝚛𝚜𝚎(𝚝𝚎𝚡𝚝, 𝚘𝚞𝚝 𝚛𝚎𝚜𝚞𝚕𝚝); Now the modifier alone is enough; the types can stay implicit: 𝚃𝚛𝚢𝙿𝚊𝚛𝚜𝚎<𝚒𝚗𝚝> 𝚙𝚊𝚛𝚜𝚎𝟷 = (𝚝𝚎𝚡𝚝, 𝚘𝚞𝚝 𝚛𝚎𝚜𝚞𝚕𝚝) => 𝙸𝚗𝚝𝟹𝟸.𝚃𝚛𝚢𝙿𝚊𝚛𝚜𝚎(𝚝𝚎𝚡𝚝, 𝚘𝚞𝚝 𝚛𝚎𝚜𝚞𝚕𝚝); ✔️ Works with scoped, ref, in, out, and ref readonly ✔️ params still forces an explicitly typed parameter list; that one's the exception 📌 If you found it helpful, then you should join my weekly .NET newsletter with 10k+ engineers. Subscribe here → http://mwaseemzakir.com Repost ♻️ would be appreciated #csharp #dotnet #dotnetcore #csharp14 #cleancode

Muhammad WaseemAug 25, 2026

Your API request was cancelled. But is your application still doing the work? 👀 One common mistake in ASP .NET Core is accepting a `CancellationToken` at the endpoint but not passing it further down. await dbContext.Users.ToListAsync(cancellationToken); When the client disconnects or cancels the request, operations that support cancellation can stop as well. Otherwise, your application may continue using: - Database connections - External API resources - CPU - Memory For a few requests, this may not be noticeable. At scale, unnecessary work starts adding up. CancellationToken is not just about cancellation. It is also about using resources responsibly. Repost ♻️ if this could help someone in your network. #dotnet #aspnetcore #csharp #backenddevelopment #webapi