Why the Old --releasever Method No Longer Works

In my previous guide, I showed how you could upgrade openSUSE Leap releases with:

sudo zypper --releasever=16.0 dup

That used to work reliably in earlier Leap versions. However, with SLE (SUSE Linux Enterprise) 16, SUSE introduced major backend and repository format changes. The new openSUSE Leap 16.0 release merges more closely with SLE infrastructure, which means the repositories and release metadata formats have changed significantly.

If you try to use the --releasever flag now, you’ll likely see repository or GPG key errors during the upgrade. That’s because the old repository layout no longer matches Leap 16’s new structure.

The New Official Method: opensuse-migration-tool

Instead of manually changing repositories, Leap 16 introduces a dedicated migration utility designed to handle all the details for you. The tool automatically adjusts your repositories, resolves new dependencies, and manages system configuration changes.

Step 1: Install the Migration Tool

First, fully update your Leap 15.6 system:

sudo zypper refresh
sudo zypper up

Then install the new migration package:

sudo zypper install opensuse-migration-tool

Step 2: Run the Migration Process

Start the migration utility:

sudo opensuse-migration-tool

The tool will analyze your current system, identify obsolete packages, and suggest repository transitions for Leap 16.0. The system prompts you to confirm before proceeding with the distribution upgrade.

You’ll want to select openSUSE Leap 16.0 with the arrow keys on your keyboard, select OK and hit Enter.

You will probably encounter the following screen about disabling third-party repositories:

This happens because Leap 16.0 changes how repositories are structured. You can simply hit Enter to confirm.

The upgrade process will then start! Wait a few minutes, then reboot into Leap 16.0 once the process finishes.

Step 3: Reboot into Leap 16.0

After the migration completes, simply reboot:

sudo reboot

You’ll now be running openSUSE Leap 16.0 with the updated repository structure.

Troubleshooting Tips

• Do not use zypper dup --releasever=16.0. It may break dependencies.
• If you encounter repository signature errors, remove or rename old .repo files in /etc/zypp/repos.d/ before re-running the migration tool.
• Ensure your disk has sufficient space and that all third-party repositories are disabled before starting the upgrade.

Final Thoughts

The openSUSE team has streamlined the upgrade path to make system migrations more reliable and aligned with SUSE’s enterprise ecosystem. While older zypper --releasever methods are now deprecated, the openSUSE Migration Tool simplifies the process and ensures compatibility with the new Leap 16 architecture.

The post Upgrade openSUSE Leap to 16.0 from 15.6 appeared first on TechOpt.

This comprehensive guide will walk you through everything you need to know, from selecting the right cable and connectors, to crimping, testing, and troubleshooting your custom cables.

Why Make Your Own Ethernet Cable?

There are several advantages to building your own network cables:

• Custom Lengths: No more coiled-up mess or cables that come up just short. Instead, you can make cables the exact length you need.
• Cost Savings: Bulk ethernet cable and connectors are far cheaper per foot than buying pre-made cables.
• Better Quality Control: You choose the cable type, shielding, and connectors, therefore avoiding cheap copper-clad aluminum (CCA) cables.
• Skill Building: This is a useful DIY skill for anyone interested in networking, home labs, or IT work.

Tools and Materials Needed

Here’s what you’ll need to make DIY ethernet cables successfully:

• Ethernet Cable (Cat6, Cat6a, or Cat5e): Prefer solid copper rather than CCA for best performance and compliance with standards. Cat6 bulk cable on Amazon
• RJ45 Connectors: Choose connectors rated for your cable type (Cat6, Cat6a, or Cat5e). Passthrough connectors are easier for beginners. Cat6 RJ45 passthrough connectors
• RJ45 Crimping Tool: Used to secure connectors to the cable. Most crimpers also include a wire cutter and stripper. RJ45 crimp tool
• Cable Tester (Recommended, but optional): Ensures your wiring is correct and detects any faults. Basic cable tester or advanced network tester
• Strain Relief Boots (Recommended, but optional): Add durability to the connector ends. Strain relief boots
• Wire Cutters/Scissors: For trimming cable and internal wires. Wire strippers/cutters

Tip: Avoid “Cat7” or “Cat8” cables sold cheaply online. These are not officially recognized Ethernet standards and often use questionable materials.

Step 1: Measure and Cut Your Cable

Pull the amount of cable you need from the box, then add roughly 30 cm (about 1 foot) of extra length for trimming and flexibility. Cut the cable cleanly using the crimper’s cutting blade or a pair of wire cutters.

Step 2: Strip the Outer Jacket

Use the stripping blade on your crimping tool (or a dedicated wire stripper) to remove 5–10 cm (2–3 inches) of the outer jacket from both ends of the cable. Be careful not to nick the internal wires.

After that, remove the internal string, if present.

At this stage, slide on the strain relief boots if you’re using them—forgetting them is a common mistake. Therefore, it’s best to add them now. You want the larger side facing outward from the end of the cable on both sides.

Step 3: Untwist and Arrange the Wires

Inside the jacket are four twisted pairs of wires (8 total). Untwist the pairs and straighten them.

Then, arrange them in either T-568A or T-568B wiring order. Use the same standard on both ends.

T-568A Wiring Order:

1. White/Green
2. Green
3. White/Orange
4. Blue
5. White/Blue
6. Orange
7. White/Brown
8. Brown

T-568B Wiring Order (Most Common in North America):

1. White/Orange
2. Orange
3. White/Green
4. Blue
5. White/Blue
6. Green
7. White/Brown
8. Brown

Lay the wires flat and keep them in the correct order. Finally, flatten them gently with your thumb for easier insertion.

Step 4: Trim Wires to Length

For non-passthrough connectors, trim the wires so that they are just long enough to reach the end of the connector when inserted. Cut them evenly so they line up perfectly.

For passthrough connectors, leave them a bit longer since the ends will protrude and be trimmed after crimping.

Step 5: Insert Wires Into the RJ45 Connector

Slide the wires into the connector carefully, ensuring they remain in the correct order. Push firmly until:

• Each wire reaches the very end of the connector.
• The outer jacket passes the strain relief tab for a strong connection.

For passthrough connectors, the wires should stick out slightly from the other side.

As soon as you confirm the order, you’re ready to crimp.

Step 6: Crimp the Connector

Place the connector into the crimping tool and squeeze firmly until the pins press down into the wires and the strain relief tab locks onto the outer jacket.

Additionally, for passthrough connectors, trim the wire ends flush with the connector after crimping.

Then, repeat this entire process for the other end of the cable!

Step 7: Test Your Cable

Use a cable tester to confirm that all eight wires are connected in the correct order.

The lights on both ends should flash in sequence.

If any wires are misaligned, cut off the connector and repeat the process on that side.

Once confirmed, your custom ethernet cable is ready for use!

Cat6 vs Cat6a vs Cat5e: Which Should You Choose?

Not all Ethernet cables are created equal. Therefore, here’s a quick comparison to help you decide:

Recommendation: Use Cat6 for most home setups, Cat6a if you want to future-proof or need maximum performance for longer runs, and Cat5e only if you already have it on hand or are working with very low-cost builds.

Frequently Asked Questions

Q: Can I mix T-568A on one end and T-568B on the other?
A: Only if you are intentionally creating a crossover cable. Otherwise, use the same wiring standard on both ends.

Q: How long can an Ethernet cable be?
A: Standard twisted-pair Ethernet cables (Cat5e, Cat6, Cat6a) are rated for up to 100 meters (328 feet) in total length. This includes patch cables at both ends. Beyond this length, you may experience signal loss or reduced speeds.

For 10 Gbps on Cat6, keep runs under 55 meters; use Cat6a for longer 10 Gbps runs.

Q: Do I really need a cable tester?
A: While optional, it saves time and frustration by catching miswires before you plug into your network.

Q: Should I ever use CCA cable?
A: No. Instead, always use solid copper cable for performance, safety, and compliance with Ethernet standards.

Troubleshooting Common Issues When Making Ethernet Cables

• Tester Shows Miswired Pair: Re-check wiring order on both ends, re-crimp if needed.
• Cable Doesn’t Click Securely: Ensure the strain relief tab is pressed down properly during crimping. Also ensure that the release tab covers on your strain relief boots aren’t too stiff and pressing down on the release tabs of the RJ45 connectors as a result. You may want to work the rubber of the strain relief boots with your thumbs a bit to stretch and break them in.
• Poor Network Speeds: Test on another device and verify that you’re using solid copper cable, not CCA.

Final Remarks

Learning how to make ethernet cables saves money, eliminates clutter, and gives you full control over your network setup. Whether you’re wiring a home office, building a home lab, or just need a few short patch cables, this DIY approach is a game changer.

Practice a few times and you’ll be making professional-quality network cables in minutes!

If you prefer a video guide, you can watch my video guide below.

The post How to Make Ethernet Cables: A Complete Step-by-Step Guide appeared first on TechOpt.

In this post, I’ll break down:

• Why next/dynamic causes flickering
• Why it’s worse with nested dynamic components
• When dynamic() is still safe to use
• A practical alternative using React.lazy() and Suspense
• What trade-offs to expect when switching

The Flickering Problem in Next.js

Using dynamic() from next/dynamic is a great way to lazy-load components and reduce your JavaScript bundle size. It also supports options like { ssr: false } to only load components on the client side.

However, when you use these components with the App Router, they often cause a flash of missing or unstyled content, especially during fast navigation or when conditionally rendering dynamic components.

Nested dynamic() calls tend to amplify this issue. For example, a parent component conditionally loading a child via dynamic(), which in turn loads another sub-component dynamically, can make the flickering more severe.

This issue has been reported in GitHub issues and community threads, but a rock-solid fix hasn’t yet made it into the framework.

Interestingly, this flicker seems to affect nested dynamic components more than top-level ones. In my testing, first-level dynamically rendered components used directly in the page file rarely exhibit the issue, which means it’s generally safe to use next/dynamic there to avoid flash of unstyled content (FOUC) during initial mount.

The Better Alternative: React.lazy() + Suspense

One workaround that has proven effective is switching from next/dynamic to native React.lazy() with Suspense. This approach introduces fewer hydration inconsistencies and minimizes flickering, even with nested lazy-loaded components.

Use next/dynamic for components initially rendered on the page, and use React.lazy() for nested components that are rendered conditionally inside those components.

Example 1: Top-level safe usage with next/dynamic

import dynamic from 'next/dynamic';
import { isSignedInAsync } from '../auth';

const PageShell = dynamic(() => import('../components/PageShell'));

export default async function Home() {
  const isSignedIn = await isSignedInAsync();

  if (isSignedIn) return null;

  return <PageShell />;
}

In this example, PageShell is conditionally rendered on the server using dynamic components. This is safe since the dynamic component is rendered with the initial HTML from the server.

Example 2: Nesting with React.lazy() and Suspense

"use client";
import dynamic from 'next/dynamic';

const NestedComponent = dynamic(() => import('./NestedComponent'));

export default function PageShell() {
  const [showNested, setShowNested] = useState(false);

  return (
    <div>
      <h1>Welcome</h1>
      <button onClick={() => setShowNested(true)}>Load Nested Component</button>
      {showNested && (
        <Suspense fallback={<div>Loading nested...</div>}>
          <NestedComponent />
        </Suspense>
      )}
    </div>
  );
}

We can safely use React.lazy() and Suspense inside our dynamically-rendered PageShell component to conditionally render our NestedComponent, and still benefit from lazy-loading and code-splitting.

If we try using the dynamic function instead of React.lazy here, we may get the Next.js dynamic flicker.

Trade-offs of Using React.lazy() Instead of dynamic

While React.lazy() and Suspense often result in smoother rendering, there are two notable downsides:

1. No Server-Side Rendering

Unlike next/dynamic, which lets you disable or enable SSR, React.lazy() only supports client-side rendering. This might hurt SEO if your component needs to be visible to crawlers.

2. Flash of Unstyled Content (FOUC) on Mount

If you do try to use React.lazy() for SSR and use it in the server-rendered HTML, React.lazy() may cause a brief flash of unstyled content because the Next.js bundler doesn’t automatically include the styles for components loaded through React.lazy() in the server-rendered HTML. This limitation can lead to inconsistent rendering.

This is why it’s best to use next/dynamic for components that are visible in the server-rendered HTML, ensuring that styles and structure are present at first paint, while reserving React.lazy() for non-critical or nested components. Using next/dynamic in the initial server-rendered HTML does not seem to cause flickering.

Final Thoughts on Preventing the Next.js Dynamic Flicker

If you’re seeing flickering with next/dynamic and conditional rendering, especially in complex nested layouts, you’re not alone. While the Next.js team continues to evolve App Router, switching to React.lazy() and Suspense where you can may provide a smoother user experience at this time.

To summarize:

• Use next/dynamic safely for top-level page components
• Use React.lazy() for nested dynamic imports to reduce flicker

The post Solving Next.js dynamic() Flicker with React.lazy appeared first on TechOpt.

> Task :react-native-device-country:prepareLintJarForPublish
> Task :react-native-device-info:createFullJarRelease
> Task :react-native-device-info:extractProguardFiles
> Task :react-native-device-info:generateReleaseLintModel
> Task :react-native-device-info:prepareLintJarForPublish
> Task :react-native-fbsdk-next:createFullJarRelease
> Task :react-native-fbsdk-next:extractProguardFiles
> Task :app:stripReleaseDebugSymbols
> Task :react-native-fbsdk-next:generateReleaseLintModel
> Task :app:buildReleasePreBundle FAILED
> Task :app:uploadCrashlyticsMappingFileRelease
[Incubating] Problems report is available at: file:///Users/dev/Documents/app/android/build/reports/problems/problems-report.html
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':app:buildReleasePreBundle'.
> Sequence contains more than one matching element.
* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights.
> Get more help at https://help.gradle.org.
Deprecated Gradle features were used in this build, making it incompatible with Gradle 9.0.
You can use '--warning-mode all' to show the individual deprecation warnings and determine if they come from your own scripts or plugins.
For more on this, please refer to https://docs.gradle.org/8.14.1/userguide/command_line_interface.html#sec:command_line_warnings in the Gradle documentation.
BUILD FAILED in 1h 6m 21s
1222 actionable tasks: 1208 executed, 14 up-to-date
node:child_process:966
    throw err;
    ^
Error: Command failed: ./gradlew bundleRelease
    at genericNodeError (node:internal/errors:984:15)
    at wrappedFn (node:internal/errors:538:14)
    at checkExecSyncError (node:child_process:891:11)
    at Object.execSync (node:child_process:963:15)
    at /Users/dev/Documents/app/buildscripts/buildserv/build/build-android.js:8:23
    at Object.<anonymous> (/Users/dev/Documents/app/buildscripts/buildserv/build/build-android.js:11:3)
    at Module._compile (node:internal/modules/cjs/loader:1529:14)
    at Module._extensions..js (node:internal/modules/cjs/loader:1613:10)
    at Module.load (node:internal/modules/cjs/loader:1275:32)
    at Module._load (node:internal/modules/cjs/loader:1096:12) {
  status: 1,
  signal: null,
  output: [ null, null, null ],
  pid: 22055,
  stdout: null,
  stderr: null
}
Node.js v20.19.3
Cleaning up project directory and file based variables 00:00
ERROR: Job failed: exit status 1

If you noticed from the stack trace above, this is a React Native app. I tried deleting my node_modules folder, deleting my build folders, running ./gradlew clean. I would run the build again and again, but nothing worked. The same error kept popping up every time, right near the end of the build.

No amount of –debug or –stacktrace was giving me any sort of additional information. The most information I could get from this error had already been given to me.

ChatGPT and Copilot were no help, suggesting that this is a Kotlin error and most likely resides in a native library I’m using within the app.

But this didn’t make sense, because I was able to build the project on my local system with the latest dependencies just fine. It was only once I sent the build to my GitLab instance, which runs the build on a macOS VM with gitlab-runner, that I started getting this error.

So is the error with the build process, or one of the build tools itself?

Narrowing Down the Cause

After a ton of googling of this error, I finally came across this Google IssueTracker post that pointed me in the right direction. This person describes the exact same issue I’m having.

This person also says that this error started happening after an upgrade to AGP 8.9.0.

Now we’re getting somewhere. It doesn’t look like they’re using React Native, but at this point I was confident the issue isn’t stemming from anything to do with React Native.

AGP is an Android build tool. It’s possible that my macOS VM has a newer version of AGP than my local system does. This would explain why it’s only happening once I send the app to build in the macOS VM.

So, what’s the problem?

Well, it can be traced back to this section here in the app’s build.gradle:

...
splits {
        abi {
            reset()
            enable enableSeparateBuildPerCPUArchitecture
            universalApk false
            include "armeabi-v7a", "x86", "arm64-v8a", "x86_64"
        }
    }
...

This section of the build.gradle file tells gradle to output different APK files for different CPU architectures.

When this part of the build.gradle file is encountered by running the bundleRelease gradle task, the “sequence contains more than one matching element” exception is thrown because bundleRelease expects to be generating a single universal AAB file instead of separate APK files, that can then be uploaded to the Google Play Store.

The Fix

All I did was remove this section from our build.gradle file:

...
splits {
        abi {
            reset()
            enable enableSeparateBuildPerCPUArchitecture
            universalApk false
            include "armeabi-v7a", "x86", "arm64-v8a", "x86_64"
        }
    }
...

And it resolved the issue! We weren’t using the multiple APKs anyways, so I’m not even sure why we had this in our build.gradle file. We only upload the single universal AAB to the Play Store.

Additional Notes

In the issue tracker linked above, Google states that they do not plan on fixing this, since they don’t officially support creating multiple APKs when running bundleRelease. However, if you still need multiple APK support, someone on the issue tracker suggests the following fix:

splits {
        abi {
            // Detect app bundle and conditionally disable split abis
            // This is needed due to a "Sequence contains more than one matching element" error
            // present since AGP 8.9.0, for more info see:
            // https://issuetracker.google.com/issues/402800800

            // AppBundle tasks usually contain "bundle" in their name
            val isBuildingBundle = gradle.startParameter.taskNames.any { it.lowercase().contains("bundle") }

            // Disable split abis when building appBundle
            isEnable = !isBuildingBundle

            reset()
            //noinspection ChromeOsAbiSupport
            include("armeabi-v7a", "arm64-v8a", "x86_64")

            isUniversalApk = true
        }
}

This enables APK splitting while disabling APK splitting for the bundleRelease task, preventing the “sequence contains more than one matching element” error.

The post Fixing ‘Sequence contains more than one matching element’ Android Build appeared first on TechOpt.

While there’s no foolproof method to detect a fake FLAC, there are some telltale signs based on bitrate and frequency response that can help you spot them. One of my go-to tools for this task is Spek, a free and open-source audio spectrum analyzer.

What Is a Fake FLAC or Fake Lossless Files?

People create fake FLAC files by converting lossy formats—like MP3 or AAC—into lossless containers such as FLAC. Although the file extension and size might suggest high quality, the underlying audio data remains compromised. These files often originate from people who re-encode lossy sources and redistribute them under the guise of high fidelity.

Also note that while FLAC is the most common lossless audio format, other containers such as WAV and ALAC do exist as well. The indicators mentioned in this article for spotting fake lossless audio files are generic and apply regardless of the container format.

Using Spek to Analyze Frequency Spectrum

When you open a file in Spek, it displays the audio spectrum across the entire track. This visual representation reveals how much of the frequency range the file actually contains. A true lossless FLAC will have no abrupt cutoffs in the upper frequencies, whereas fake FLACs often exhibit sharp drop-offs.

Here’s a general guideline for identifying the cutoff frequencies and their corresponding bitrates:

• 11 kHz = 64 kbps
• 16 kHz = 128 kbps
• 19 kHz = 192 kbps
• 20 kHz = 320 kbps

If you notice a sharp cutoff around these frequencies, the file may have been upsampled from a lossy source.

What to Expect from True Lossless FLACs

Depending on the sample rate and bit depth, a legitimate FLAC file should show frequency content extending to the upper limits of the spectrum:

• 44.1 kHz, 16-bit: Should display frequencies up to 22 kHz
• 48 kHz, 16-bit: Should reach up to 24 kHz
• 96 kHz, 24-bit: May extend up to 48 kHz, but a smooth fade to nothing somewhere between 20-30 kHz is normal
• 192 kHz, 24-bit: May extend up to 96 kHz, but a smooth fade to nothing somewhere between 20-30 kHz is normal

You can often spot upsampling when you see a sharp cutoff at 22 kHz. There may also be very faint or random noise in the 22 kHz and up range. This pattern usually means someone took a 44.1 kHz file and padded it to 48 or 96 kHz.

It’s also worth noting that there’s ongoing debate about whether audio content above 20 kHz contributes meaningfully to music. An audio engineer or producer might even intentionally apply a low-pass filter to cut out all frequencies above a certain inaudible range. This will result in a steeper drop-off, even in a genuine lossless file.

Additionally, not all instruments produce frequencies in this high range, so a natural lack of content above 20 kHz doesn’t necessarily indicate the file is fake.

Bitrate as Another Indicator of a Fake FLAC

Another clue is the file’s bitrate. While FLAC is a variable bitrate format, files with noticeably low average bitrates may be suspect. Here are some average bitrate ranges you might expect from real FLAC files:

• 44.1 kHz / 16-bit (CD quality): ~700–1100 kbps
• 48 kHz / 16-bit or 24-bit: ~800–1400 kbps
• 96 kHz / 24-bit: ~2000–3000 kbps (can vary widely depending on the content)
• 192 kHz / 24-bit: ~4000–7000 kbps (can vary widely depending on the content)

If you see a file with a much lower bitrate than expected and frequency cutoffs that match the patterns listed above, the file is almost certainly a fake FLAC.

Trust Your Ears

While visual analysis is helpful, always trust your ears. A song that sounds dull, muffled, or artifacted is likely not true lossless. That said, some minimal or acoustic recordings might not use the entire frequency spectrum and can still be genuine FLACs.

For example, a solo vocal track, acoustic guitar piece, or lo-fi bedroom recording may naturally have limited frequency content, especially in the high end. These types of recordings often focus on midrange clarity rather than full-spectrum detail, so a sparse frequency graph in Spek doesn’t always mean the file is fake.

Final Thoughts

Detecting fake FLAC files takes a combination of tools, knowledge, and critical listening. While Spek and bitrate guidelines provide strong indicators, no method is 100% reliable. Still, by learning to recognize the red flags, you can better curate a truly lossless music library.

The post How to Identify Fake FLAC Files appeared first on TechOpt.

There are benefits to using a Microsoft account with your PC, but you might still want to use a local account. Some people prefer using a local account for administrative or privacy reasons. Also, you can always sign-in to a Microsoft account at a later time.

You can still create a local account during initial setup, but it’s harder than before. Here are the steps for skipping Microsoft account login and creating a local account in newer versions of the Windows 11 Home out-of-box setup experience.

1. Proceed Through Initial Setup Until the Microsoft Account Screen

Proceed through the initial setup steps by configuring the options and clicking Next. You’ll eventually wind up at the Microsoft account screen.

2. Open Command Prompt from Setup with SHIFT+F10

Once you’re in the initial setup wizard shown above, press SHIFT+F10 on your keyboard. This will open a command prompt window.

3. Type start ms-cxh:localonly and Hit Enter

Click inside of the command prompt window and type start ms-cxh:localonly.

Hit Enter.

4. Create a Local Account

A new screen will open to create a local account. Type a username, password and choose your security questions.

When you’re done, simply click Next to proceed to the desktop as you normally would!

Remarks

• Although you can technically run this command at the beginning of setup, it’s best to get to the Microsoft account screen first to easily configure your system’s region, keyboard settings and network.
• As of right now, you can still create a local account on Windows 11 Pro and Enterprise versions from the setup wizard.
• My opinion is that this clearly shows the direction Microsoft is taking with its consumer line of products. They want us to be reliant on their cloud as much as possible!

Update 05/08/2025: The command previously suggested in this article, oobe\bypassnro, has been disabled by Microsoft as of Windows 11 build 26100. Only the start ms-cxh:localonly command should be used going forward.

If you prefer a video to follow along, you can watch the tutorial on my YouTube channel down below:

The post Local Account Creation During Windows 11 Setup appeared first on TechOpt.

Why Is App Center Being Discontinued?

App Center has been a go-to choice for mobile developers, providing CI/CD capabilities, automated testing, and distribution for iOS and Android apps. However, Microsoft has decided to sunset the platform, leaving teams to find replacement services that meet their needs. Therefore, selecting the right alternative is crucial. The key factors in choosing an alternative include build automation, real-device testing, seamless app distribution, and over-the-air (OTA) updates.

Best App Center Alternatives for React Native

1. EAS (Expo Application Services)

For teams using EAS, it provides an all-in-one solution for building, updating, and distributing React Native apps. As a result, it is one of the best alternatives to App Center, especially for projects already leveraging Expo.

• Pros:
  • Seamless integration with Expo projects
  • No need for local machine setup
  • Cloud-based builds for iOS and Android
  • EAS Update serves as an alternative to CodePush, allowing for seamless OTA updates
• Cons:
  • Primarily geared toward Expo-managed projects
  • Limited flexibility for bare React Native apps

2. Hot Updater (Self-Hosted CodePush Alternative)

If you relied on App Center for CodePush, a crucial feature for deploying over-the-air updates, you need a replacement. Fortunately, one of the best open-source alternatives is Hot Updater. This is my personal favourite CodePush replacement. It provides similar functionality while allowing you to self-host your own OTA update solution.

• Pros:
  • Self-hosted, offering full control over updates
  • Supports both iOS and Android
  • Intuitive web console for managing versions
  • Plugin support for various storage providers (AWS S3, Supabase, etc.)
• Cons:
  • Requires infrastructure setup and maintenance
  • Needs DevOps expertise for proper implementation

3. Bitrise

Bitrise is one of the most popular CI/CD platforms for mobile development. It offers cloud-based automation, supports React Native out of the box, and provides a flexible pipeline system for building, testing, and deploying apps. Consequently, many teams transitioning from App Center have found it to be a reliable alternative.

• Pros:
  • Pre-configured workflows for React Native
  • Easy integration with GitHub, GitLab, and Bitbucket
  • Supports both iOS and Android
• Cons:
  • Limited free-tier resources
  • Learning curve for advanced workflow customization

4. Codemagic

Codemagic is another excellent CI/CD tool that specializes in mobile development. It supports React Native projects and simplifies the build and deployment process with minimal configuration. Additionally, its user-friendly approach makes it a strong choice for teams looking for a quick transition.

• Pros:
  • Optimized for React Native
  • Automated iOS code signing
  • Integration with Google Play and App Store
• Cons:
  • Can get expensive for teams with heavy usage
  • Limited concurrent builds on the free plan

5. Firebase App Distribution

If your primary need is distributing pre-release versions of your app, Firebase App Distribution is a great alternative to App Center’s distribution feature. Moreover, it integrates well with other Firebase tools, making it an appealing choice for teams already using Firebase.

• Pros:
  • Easy tester management
  • Integrates with Firebase Crashlytics for monitoring
  • Works for both iOS and Android
• Cons:
  • No built-in CI/CD
  • Requires additional tools for automated builds

Choosing the Right App Center Alternative for Your React Native Project

The best App Center alternative depends on your specific needs:

• For full CI/CD: Bitrise or Codemagic
• For scalable builds: CircleCI
• For Expo projects: EAS (Expo Application Services)
• For simple app distribution: Firebase App Distribution
• For over-the-air updates (CodePush alternative): Hot Updater

As App Center sunsets, transitioning to a new platform early will help ensure a smooth workflow. Consequently, by selecting the right alternative, you can continue to build, test, distribute, and update your React Native apps with minimal disruption.

The post App Center Alternatives for React Native Developers appeared first on TechOpt.

Warning

Use this method at your own risk. Modifying HTML responses through Nginx can easily break your webpage if not handled carefully. Always test changes in a controlled environment before deploying them to production.

Nginx is not designed for content manipulation, and this approach should only be used as a last resort. Before proceeding, exhaust all other options, such as modifying the source code, using a built-in integration, or leveraging a client-side solution.

How to Add a Script to HTML Using Nginx

If you need to add a script, or any other HTML to an HTML file using Nginx, you can use the sub_filter module to modify response content on the fly. By leveraging this, we can insert a <script> tag before the closing </head> tag in the HTML document.

Configuration Example

To achieve this, add the following to your Nginx configuration:

server {
    listen 80;
    server_name example.com;

    location / {
        proxy_pass http://backend;
        proxy_buffering off;

        sub_filter '</head>' '<script src="https://example.com/analytics.js"></script></head>';
        sub_filter_types text/html;
        sub_filter_once on;
    }
}

Explanation

• sub_filter '</head>' '<script src="https://example.com/analytics.js"></script></head>': This replaces </head> with our script tag, ensuring it appears in the document head.
• sub_filter_types text/html;: Ensures the filter applies only to HTML responses.
• sub_filter_once on;: Ensures that the replacement happens only once, as </head> should appear only once in a valid HTML document.

Adding an Nginx Proxy for Script Injection

To implement this solution without modifying the existing helpdesk software, I set up another Nginx instance in front of it. This new Nginx proxy handles incoming requests, applies the sub_filter modification, and then forwards the requests to the helpdesk backend.

Here’s how the setup works:

1. The client sends a request to example.com.
2. Nginx intercepts the request, modifies the HTML response using sub_filter, and injects the script.
3. The modified response is then sent to the client, appearing as if it were served directly by the helpdesk software.

This approach keeps the original application untouched while allowing script injection through the proxy layer.

Remarks

• Nginx is primarily a proxy and web server, not a content manipulation tool. Modifying content in this way should be a last resort after exhausting all other options, such as modifying the source code, using a built-in integration, or leveraging a client-side solution. Overuse of sub_filter can introduce unexpected behavior, break page functionality, or impact performance.
• sub_filter requires proxy_buffering off;, which may degrade performance, especially for high-throughput sites, by preventing response buffering and increasing load on the backend.
• If you’re adding multiple scripts or need flexibility, consider using a tag manager such as Google Tag Manager instead.
• You can use this method to modify or inject any HTML, not just scripts.

The post Adding a Script Tag to HTML Using Nginx appeared first on TechOpt.

When setting up a new environment, you might wonder whether you should deploy your workload inside an LXC container or a full VM. The choice depends on what you are trying to achieve.

LXC Containers: Lightweight and Efficient

LXC (Linux Containers) provides an efficient way to run isolated environments on a Proxmox system. Unlike traditional VMs, containers share the host system’s kernel while maintaining their own isolated user space. This means they use fewer resources, start up quickly, and offer near-native performance.

When to Use LXC Containers:

• Single Applications – If you need to run a single application in an isolated environment, an LXC container is an excellent choice.
• Docker Workloads – If an application is only available as a Docker image, you can run Docker inside an LXC container, avoiding the overhead of a full VM.
• Resource Efficiency – LXC containers consume fewer resources, making them ideal for lightweight applications that don’t require their own kernel.
• Speed – Since LXC containers don’t require full emulation, they start almost instantly compared to VMs.

Considerations for LXC Containers:

• Less Isolation – Since they share the host kernel, they are not as isolated as a full VM, which can pose security risks if an attacker exploits vulnerabilities in the kernel or improperly configured permissions.
• Compatibility Issues – Some applications that expect a full OS environment may not work well inside an LXC container.
• Limited System Control – You don’t have complete control over kernel settings like you would in a VM.

Virtual Machines: Full System Isolation

Virtual machines in Proxmox use KVM (Kernel-based Virtual Machine) technology to provide a fully virtualized system. Each VM runs its own operating system with its own kernel, making it functionally identical to a physical machine.

When to Use Virtual Machines:

• Multiple Applications Working Together – If you need to run a system with multiple interacting services, a VM provides a fully isolated environment.
• Custom Kernel or OS Requirements – If your application requires a specific kernel version or a non-Linux operating system (e.g., Windows or BSD), a VM is the way to go.
• Strict Security Requirements – Since VMs have strong isolation from the host system, they provide better security for untrusted workloads.
• Compatibility – Any software that runs on a physical machine will run in a VM without modification.

Considerations for Virtual Machines:

• Higher Resource Usage – VMs require more CPU, RAM, and disk space compared to containers.
• Slower Start Times – Because they emulate an entire system, VMs take longer to boot up.
• More Maintenance – You’ll need to manage full OS installations, updates, and security patches for each VM separately.

Final Thoughts: When to Choose LXC Containers vs. Virtual Machines in Proxmox

In general, if you need to run a single application in isolation, or if your application is only available as a Docker image, an LXC container is the better choice. Containers are lightweight, fast, and efficient. However, if you’re running a more complex system with multiple interacting applications, need complete OS independence, or require strong isolation, a VM is the better solution.

Proxmox makes it easy to work with both LXC and VMs, so understanding your workload’s needs will help you choose the right tool for the job. By leveraging the strengths of each, you can optimize performance, security, and resource usage in your environment.

The post LXC Containers (CTs) vs. Virtual Machines (VMs) in Proxmox appeared first on TechOpt.

Tailwind CSS has solidified its place in the modern web development ecosystem, offering a utility-first approach that streamlines styling for complex projects. While Tailwind is a powerful tool, it’s not a one-size-fits-all solution. In 2025, Tailwind is more popular than ever, but there are cases where it may not be the best choice. Let’s break down when to use Tailwind, and when to consider alternatives.

When to Use Tailwind CSS

1. Complex, Multi-Page Websites

Tailwind shines in large-scale, multi-page applications where design consistency is critical. With reusable utility classes, developers can ensure a unified UI without wrestling with conflicting styles from separate CSS files. Platforms like SaaS applications, dashboards, and content-heavy websites benefit immensely from Tailwind’s scalable approach.

2. Rapid Prototyping

If speed is a priority, Tailwind helps teams iterate faster. Its utility classes allow developers to style components directly in markup, reducing the need for custom CSS. This makes it ideal for MVPs, startup projects, and proof-of-concept applications where time-to-market is crucial.

3. Projects Requiring Design System Enforcement

Tailwind is a great fit for teams that need strict adherence to a design system. The ability to define custom themes, typography, and color palettes in the tailwind.config.js file ensures that styles remain consistent across all pages and components.

Tailwind CSS version 4, which was just released, takes this a step further. This new version of Tailwind allows for most configuration to be done right inside of your main CSS file.

4. Component-Based Frameworks (React, Vue, Svelte, Next.js, etc.)

For teams using modern frameworks, Tailwind works seamlessly with component-driven development. It allows styling to live alongside the component logic, promoting maintainability and reducing CSS file bloat.

5. Web Apps with a Long Development Lifecycle

Maintaining large applications is easier with Tailwind since it reduces CSS complexity. Unlike traditional CSS or preprocessor-based approaches, Tailwind minimizes global styles, making it easier to refactor and extend applications over time.

When Not to Use Tailwind CSS

1. Small, Static Websites or Simple Landing Pages

For one-page websites or simple marketing pages, Tailwind may be overkill. A minimal custom CSS file or even plain HTML/CSS may suffice. Using Tailwind in such cases could add unnecessary overhead without significant benefits.

2. Highly Unique, Artistic Designs

While Tailwind is flexible, highly creative or experimental designs with intricate animations, custom typography, and complex layouts might be better served with traditional CSS, SCSS, or CSS-in-JS. Tailwind’s structured approach may feel limiting for designers who prefer complete freedom over styles.

3. Teams Without Tailwind Experience

Despite its advantages, Tailwind has a learning curve. Developers unfamiliar with its utility-first approach may struggle initially. If a team lacks experience or doesn’t have time to invest in learning Tailwind, sticking to traditional CSS methodologies may be more efficient.

4. Legacy Codebases with Predefined Styles

If you’re working on a legacy project that already has well-structured CSS or a component library, integrating Tailwind could introduce inconsistencies and unnecessary complexity. Migrating to Tailwind in such cases should be a carefully considered decision.

5. Strict SEO or Performance-Optimized Websites Where Every KB Counts

While Tailwind’s PurgeCSS ensures minimal CSS footprint, in some ultra-performance-critical cases, writing minimal, handcrafted CSS might still be preferable. Projects that need to prioritize reducing external dependencies might opt for vanilla CSS instead.

Conclusion: When to use Tailwind CSS in 2025

Tailwind CSS is a top choice for complex, multi-page applications, design-consistent systems, and component-driven frameworks in 2025. However, it’s not always the best tool for every scenario.

For small static sites, highly creative designs, or legacy projects, traditional CSS approaches may still hold an advantage. Understanding when to use Tailwind, and when not to, will help you maximize efficiency while maintaining flexibility in your web development workflow.

The post When to Use (and Not Use) Tailwind CSS in 2025 appeared first on TechOpt.