About Code Royale

Code Royale is a real-time competitive coding arena where developers battle 1v1 through live multiple-choice and code-analysis challenges. Pick an arena, get matched against a real opponent or the bot, and fight round by round to climb the Elo ladder.

Who built it

Code Royale is built and maintained by Eduardo Dionisio Fernandes, a software engineer with 20+ years of experience — primarily in C++ systems programming — working remotely from Brazil. You can find him at dionisio.dev, on X at @dionisiodev, and on GitHub.

Why it exists

It grew out of a simple frustration: there are plenty of places to learn to code, but very few that make testing your knowledge feel like a game — fast, competitive and full of adrenaline. Code Royale turns what is usually a solo grind (reviewing data structures, language semantics, security concepts) into a match you actually want to start.

How it works

• Arenas — each arena is a domain (DSA, Python, Go, JavaScript, Cybersec, C and more) with its own Elo rating and leaderboard.
• Battles — a match is a series of timed rounds; each round is a multiple-choice or code-analysis challenge. Answer faster and correctly to win.
• Ranking — every win or loss moves your Elo. Badge tiers (Bronze → Platinum) reflect your standing.
• Modes — ranked 1v1, practice against the bot, a daily challenge, and challenge-a-friend duels.

The challenge bank

Challenges are curated and reviewed by engineers — not randomly generated. The set is maintained and corrected over time. If you spot an error, you can flag it from the challenge review flow and it will be fixed.

Editorial principles

• Accuracy first — challenges are fact-checked and corrected when reported.
• We don't claim credit for standard computer-science concepts.
• This is a game and a learning tool, not a content farm — every page has a purpose.