linux-live.org

A free hosted REST API like ReqRes gives you a real HTTP endpoint you can call immediately—no signup, no local server, no database setup. You get predictable JSON responses for users, resources, login, and registration, which makes it useful for front-end demos, integration tests, learning HTTP clients, and prototyping. What it is not is a production backend for your app: the data is shared, resets periodically, and you don't control the schema. If you need persistent, private data with auth and logs, that's where an account-based backend or a commercial licence comes in.

What "free REST API for testing and prototyping" actually means

The phrase sounds vague, so it helps to separate two things people often conflate:

• A mock/sample API — a public, hosted service with fixed or semi-fixed endpoints that return realistic-looking JSON. You don't own the data. It exists so you can point code at a URL and get a response.
• A real backend you configure — a service where you define collections, schemas, authentication, and logging, and where your data persists and belongs to you.

ReqRes's landing page describes both: a free REST API for testing and prototyping with real responses and no signup, plus an option to build your own backend with collections, auth, and logs at app.reqres.in. Those are different products with different trade-offs. The free public endpoints are the "point and go" part; the account-based backend is the "own your data" part.

What you can do with the no-signup public endpoints

1. Front-end demos without a backend

If you're building a UI and need data to render, you can fetch from a public endpoint instead of hardcoding arrays. This keeps your demo code closer to real fetch logic:

async function loadUsers(page = 1) {
  const res = await fetch(`https://reqres.in/api/users?page=${page}`);
  if (!res.ok) throw new Error(`HTTP ${res.status}`);
  const { data, total, page: current } = await res.json();
  return { users: data, total, page: current };
}

You get pagination fields, a data array, and support metadata—enough to build list views, loading states, and empty states.

2. Integration and contract tests

You can assert that your HTTP layer handles status codes, headers, and JSON shapes correctly. Typical checks:

• GET /api/users/2 returns 200 with a data object.
• GET /api/users/23 returns 404 (a non-existent user).
• POST /api/login with valid credentials returns a token; with missing fields returns 400.

This is useful for testing your client wrapper, retry logic, error handling, and serialization—without spinning up your own server.

3. Learning HTTP clients and tooling

If you're new to fetch, Axios, curl, Postman, or HTTPie, a hosted API is a low-friction target. You can practice:

• Sending query parameters (?page=2, ?delay=3).
• Setting headers and reading response headers.
• Handling POST, PUT, PATCH, DELETE.
• Observing status codes for success and failure.

4. Deliberate failure and latency testing

Endpoints that return 404 on purpose, or that accept a delay parameter, let you test how your app behaves when things go wrong or slow down. That's hard to do reliably against a happy-path local mock.

What the public endpoints are not good for

The key limitation: you don't own the data, and other people are hitting the same endpoints. Treat responses as illustrative, not authoritative.

When you'd move to an account-based backend

Consider app.reqres.in (collections, auth, logs) when any of these are true:

• You need your own collections and fields, not the fixed demo schema.
• You need data to persist between sessions and belong only to you.
• You need real authentication flows you can rely on in a demo or internal tool.
• You need request logs to debug what your client actually sent.
• You're working with a team and need shared, stable endpoints.

The trade-off is setup and, eventually, cost. The public endpoints require none; the backend requires an account and configuration.

Where pricing and licensing become relevant

The site signals a commercial licence and an upgrade path (with Stripe as the payment platform), but specific prices, plan tiers, and limits aren't stated here—so don't assume numbers. What you can reason about:

• Prototyping and learning → free public endpoints are usually enough.
• Internal tools, demos for clients, or anything you don't want reset → an account-based backend is the natural next step.
• Production or commercial use → check the licence terms and any paid plan, because "free for testing" and "free for commercial production" are not the same thing.

Before committing, read the current terms on the site rather than relying on secondhand summaries, since pricing and licence scope change.

A quick decision checklist

1. Do you need data that persists and is private? If yes → account-based backend.
2. Do you need a custom schema? If yes → account-based backend.
3. Are you only testing HTTP behavior, UI rendering, or learning a client? If yes → free public endpoints.
4. Will this touch real users or revenue? If yes → review the licence and any paid plan first.
5. Do you need logs and team access? If yes → account-based backend.

If you answer "no" to 1, 2, 4, and 5, the free hosted API is likely all you need. If you answer "yes" to any of them, plan for the account-based path.

Linux Live Kit is a set of shell scripts that turns an existing Linux installation into a bootable Live system. You install your favorite distribution to a disk partition or a folder, run the build script, and get an ISO image plus a TAR archive you can write to a USB device. It is a build toolkit, not a ready-made distribution — you supply the Linux system, and Linux Live Kit packages it.

What it actually produces

Running the build script creates two artifacts in /tmp:

• An ISO image — a bootable CD/DVD image of your system.
• A TAR archive — the same content packaged for USB devices. You unpack it to the USB device and run bootinst.sh from the boot sub-directory to make the device bootable in both Linux and Windows.

How the build works

The documented workflow has six steps:

1. Install your distro to a disk partition, or into a folder on your existing system. Debian is recommended but not required.
2. Verify kernel support for squashfs and either aufs or overlayfs. Most distributions support these automatically.
3. Remove unnecessary files (optional) to shrink the Live system. The docs specifically recommend removing udev's persistent net rules and similar settings, since they can prevent the system from working correctly on different hardware.
4. Download Linux Live Kit from GitHub and place it in /tmp. You can read the files in ./DOC/ to understand how it works, and edit .config to modify variables.
5. Log in as root and run ./build. The ISO is created in /tmp.
6. For a bootable USB, unpack the generated TAR archive (also in /tmp) to your USB device and run bootinst.sh from the boot sub-directory.

What it improves over the old Linux Live scripts

The project compares itself to the older Linux Live scripts (last released in 2011):

When this is the right tool

Choose Linux Live Kit if you already have a working Linux system you want to turn into a portable, bootable copy — for example, a developer who wants to carry a configured environment on a USB stick, or someone building a custom rescue or demo image. The persistent-changes feature via DynFileFS is the key advantage for USB use, since it lets you save changes even on VFAT or NTFS drives.

It is not the right choice if you want a prebuilt Live distribution to download and run. Linux Live Kit gives you the scripts and the process; the distribution content comes from your own installation.

Before you run the build script, verify three things: your kernel supports squashfs plus either aufs or overlayfs, your source system has been cleaned of hardware-specific settings, and you know how you want persistent changes to work. Linux Live Kit is a set of shell scripts that turns an installed Linux system into a Live ISO, so most failures trace back to one of these prerequisites rather than the scripts themselves.

Kernel module support

The build depends on two kernel capabilities:

• squashfs — compresses your filesystem into the Live image. Linux Live Kit's squashfs supports XZ compression including BCJ filters, which is where the compression ratio and decompression speed come from.
• aufs or overlayfs — provides the writable overlay layer on top of the read-only compressed filesystem. The current kit uses aufs or overlayfs instead of the older unionfs, which the project describes as a stability improvement.

Most distributions ship these modules already, so the practical check is simply confirming they load. If your kernel lacks them, the build or boot will fail regardless of anything else you configure.

Preparing the source system

The recommended starting point is a normal installation of your favourite distro — Debian is recommended but not required — either on a disk partition or in a folder on your existing system.

Two cleanup steps matter for cross-hardware behaviour:

1. Remove udev's persistent net rules and similar distro-specific settings. These bind network interface names and other configuration to the machine you built on. Left in place, they can stop the Live system from working correctly on different hardware.
2. Delete unnecessary files to shrink the image. This step is optional, but a smaller source system produces a smaller Live ISO.

Persistent changes and storage

If you want changes to survive a reboot, that depends on DynFileFS, which provides dynamic-size filesystem support. It can write persistent changes even to VFAT or NTFS, so a USB stick formatted with those filesystems is a valid target — you are not limited to a Linux-native filesystem.

What the build produces

After logging in as root and running ./build, the Live Kit ISO image is created in /tmp. For a bootable USB, unpack the generated TAR archive (also in /tmp) onto your USB device and run bootinst.sh from the boot sub-directory. That install script is what makes the device boot under both Linux and Windows.

Quick pre-build checklist

If all five are settled, the build itself is the least likely part to go wrong.

Linux Live Kit builds a bootable Live ISO from a Linux installation you already have. You install your preferred distribution to a disk partition or a folder, confirm the kernel supports squashfs plus aufs or overlayfs, then download the kit to /tmp, optionally edit .config, and run ./build as root. The resulting ISO and TAR archive land in /tmp; unpack the TAR to a USB device and run bootinst.sh to make it bootable. This works best when you start from a clean, minimal installation — Debian is recommended but not required.

What you need before starting

• A Linux distribution installed either to a disk partition or into a folder on your existing system.
• Kernel support for squashfs and either aufs or overlayfs. Most distributions include these automatically, but you should verify.
• Root access, since the build script must run as root.
• Enough free space in /tmp for the generated ISO and TAR archive.

Step-by-step build

Step 1: Install your distribution

Install your favourite distro to a disk partition, or into a folder on your existing system. Debian is recommended but not required — any distribution should work if the kernel modules below are available.

Step 2: Confirm kernel module support

Make sure squashfs and either aufs or overlayfs are supported by your kernel. Chances are your distribution supports them automatically. If not, you will need to enable them before the build can succeed.

Step 3: Trim unnecessary files (optional)

Remove all unnecessary files to make the Live Linux system as small as possible. This step is optional but recommended. It is also recommended to remove udev's persistent net rules and other distribution-specific settings, which may prevent the system from functioning correctly on different hardware.

Step 4: Download Linux Live Kit

Download Linux Live Kit from GitHub and put it in /tmp. Reading the files in ./DOC/ to learn how it works is optional. If you need to modify variables, edit the .config file.

Step 5: Run the build script

Log in as root and run:

./build

Your Live Kit ISO image will be created in /tmp.

Step 6: Make a bootable USB

To make a bootable USB, unpack the generated TAR archive (also from /tmp) to your USB device, then run bootinst.sh from the boot sub-directory. The install script can make your device boot in both Linux and Windows.

What the kit gives you

Linux Live Kit uses aufs or overlayfs instead of the older unionfs, which brings greater stability. squashfs supports XZ compression including BCJ filters for a strong compression ratio and fast decompression. The CD tree is simplified, so you can name your distro whatever you like (for example slax or knoppix). It supports booting from USB devices as well as CD/DVD discs, and DynFileFS provides dynamic-size filesystem support for writing persistent changes even to VFAT or NTFS. You can also load your LiveKit data from a different directory or even from an ISO file.

Common snags

• Missing kernel modules. If squashfs or your chosen union filesystem is not available, the build will fail. Check this before Step 4.
• Hardware-specific settings. Persistent net rules and similar distro settings can stop the Live system from working on different hardware — remove them in Step 3.
• Not running as root. The ./build script requires root; running it as a normal user will not produce the ISO.
• Forgetting the second stage for USB. The ISO alone is not enough for a USB stick — you must unpack the TAR and run bootinst.sh.

Linux Live Kit replaces the old Linux Live scripts (last released in 2011) with a more stable and flexible toolkit. The main changes: it uses aufs or overlayfs instead of unionfs, adds squashfs XZ compression with BCJ filters, simplifies the CD tree so you can name your distro anything, and introduces DynFileFS for persistent changes on VFAT or NTFS. If you only need to know whether upgrading is worth it, the short answer is yes — the stability and persistence improvements address the two biggest weaknesses of the 2011 scripts.

Stability: unionfs replaced by aufs or overlayfs

The old scripts relied on unionfs, which was known to be less stable. Linux Live Kit uses aufs or overlayfs instead, which the project describes as bringing "great stability and features."

What this means in practice: a live system stacks a read-only filesystem (the compressed squashfs image) with a writable layer. If that stacking layer is fragile, you get crashes or corrupted writes during a session. Switching to aufs/overlayfs reduces that class of failure.

Condition to check: your kernel must support squashfs and either aufs or overlayfs. Most distributions ship these modules already, so this is usually automatic.

Compression: squashfs with XZ and BCJ filters

Linux Live Kit's squashfs supports XZ compression, including BCJ filters. The project claims this gives an "incredible compression" ratio alongside "amazing decompression speed."

Why BCJ matters: branch-conversion (BCJ) filters pre-process executable code so the compressor handles it more efficiently. The result is a smaller ISO without a proportional penalty at boot time.

Practical effect: you can fit more into the same image size, or shrink an existing image, compared to the older compression path.

Simplified CD tree and custom distro naming

The CD tree is simplified, and you can call your distro whatever you like — for example slax or knoppix. The old layout constrained naming; now the branding is yours.

This matters if you are distributing a customized live system and want the boot menu and directory structure to reflect your own name rather than a fixed one.

Persistent changes: DynFileFS on VFAT and NTFS

The old scripts had no dynamic-size persistent storage. Linux Live Kit adds DynFileFS, a dynamic-size filesystem that supports writing persistent changes even to VFAT or NTFS.

This is the change with the most day-to-day impact:

• Dynamic size — the persistence file grows as needed instead of being fixed upfront.
• VFAT/NTFS support — you can keep changes on the same USB stick you already formatted for Windows compatibility, without reformatting to a Linux filesystem.

If your goal is a USB stick that boots Linux, saves your settings, and still works as a normal Windows-readable drive, this is the feature that makes it possible.

Other additions

• USB booting in addition to CD/DVD discs.
• Loading LiveKit data from a different directory or even from an ISO file.
• An install script to make your device boot in both Linux and Windows.

Quick comparison

When the upgrade matters most

• You hit instability with the old scripts — the aufs/overlayfs switch is the direct fix.
• You need persistence on a Windows-compatible USB stick — DynFileFS on VFAT/NTFS is the reason to move.
• You want a smaller image — XZ with BCJ filters is the relevant change.
• You are rebranding a live distro — the simplified tree and custom naming remove the old constraint.

If you are already running the 2011 scripts on a stable system with no persistence needs, the upgrade is optional. For anything involving USB persistence or long sessions, the new toolkit is the better base.