The Range is Live

We call it The Range, as in "hey, you gonna hit The Range today?" Distinct from the static pedagogy currently being built to teach techniques, The Range is where you go to put it all together. Test your mettle against others, a fresh set of objectives every day.

What It Is

When the clock hits 00:00 UTC, a target comes online. When you connect, you are provisioned your very own attack terminal preconfigured with all the tools you need for success. You will be greeted with the day's objectives — find this IP, name that user, decrypt these files. You'd better hurry, though, because only the first player to submit the answer gets the credit.

Why and How

CLI-Games is an ecosystem. Our dream is to build a vast, rich library of games leading to emergent experiences that scale with your ability to exploit it, all interconnected by a mesh of social features. Standing up a CTF is a natural addition to that vision. Besides being extremely popular and a great tool for building in-demand skills in a fun way, we want you to take what you learn here into Dial-Up Days or Neon Descent (forthcoming) and use it to find new ways to beat them.

We started with some static levels teaching fundamental concepts. I'll be straight here — building them has been a struggle. We are basically trying to assemble the plane in mid-air, and it's painstaking. Knowing that live challenges were on the docket, we took a break from building out the static pipeline and implemented the daily challenge. It went surprisingly smooth.

By integrating Linux containers for the challenge, Claude was suddenly free from the burden of having to build a semi-OS from scratch while simultaneously designing the levels. I was blown away by the result. Whereas previously, the levels were all polluted with LLM artifacts — fourth-wall breaks, logical inconsistencies, giving away the answers — the live challenges were drafted masterfully. Each level Claude came up with was tight, consistent, solvable, and taught exactly the right skills in the right way. I have been taking lessons myself as a byproduct of playtesting them and learning more this way than I ever did in college.

The next step is to use The Range to turn around and inform the existing static CTF implementation. If The Range is where you prove what you know, the skills tree is where you go to find the answers.

How Do I Play?

1. Type range or daily ctf in the terminal 2. If an event is live, you'll connect straight to your attack box and find the scenario along with your objectives 3. Submit answers with the submit command 4. Watch the live scoreboard and activity feed in the sidebar

The sidebar shows connected players, objectives captured, and a running activity feed. You can see who captured what and when. A countdown timer shows how much time remains in the current event.

The Architecture

For those curious about the implementation details: your browser connects over WebSocket to a Go bridge running on our infrastructure. The bridge provisions a fully isolated environment for each player — your own private network, your own target, and your own attack box. Nobody else can see your commands or interfere with your session. If you disconnect, your environment persists for up to two hours so you can reconnect without losing state. When the timer runs out, an automated turnover script destroys all environments and redeploys from a preloaded challenge definition seed. These config files are hashed out between Frank and Claude separately and loaded into the queue.

Future Direction

We are just getting our feet wet. Frontloading scalability, we are taking it nice and slow and optimizing the challenge rollout process. Currently, the architecture supports one player and one machine, with plans to expand to support a multi-machine target network and teams of multiple players. This is still very much being actively written. If you are a CTF veteran or a newb with opinions, please get in contact.

Additional features under consideration include:

• At defined intervals, hints will be broadcast to all players at the same time (to keep things moving)

• Lifetime stats on your profile and leaderboards

• Spectator mode for watching events in progress

• Larger events with more challenges, requiring cooperation, and with longer windows

• Challenge definitions that approximate the rapidly changing realities of the industry

If you are still reading, you are a future OG in the making. Sign up, participate, give me your feedback. Become involved. This site won't stay free forever, and those who were here since the beginning will be honored.

The Range is a live daily CTF running on real Linux infrastructure inside CLI-Games. Learn more about how it works or read about why we built CTF training this way.