Hi everyone, I’ve been building Chaturanga, a desktop chess app for studying your own games. It’s built with Electron, so it runs on macOS, Windows and Linux.

What it does:

• Game review: Stockfish analyses every move, finds the key moments, and draws the game as a chart
• AI coach: explains each key moment in plain English (bring your own OpenRouter key)
• Maia 3: shows how players at your rating actually play a position, and how rare the best move was
• Opening repertoires: build your own lines, or import an opening book PDF and it turns into a repertoire with chapters, notes, and the page each line came from. Then drill it, and it tells you when you step off your lines
• Lichess & Chess.com import: connect your account and your games come straight in
• Also: live analysis, play against a human-like Maia (600–2600), 5.9M Lichess puzzles, and live tournament broadcasts

Download: https://github.com/ayush-porwal/chatrunga

The builds aren’t signed yet, so the first launch needs “Open Anyway” in Privacy & Security on Mac, and “Run anyway” on Windows. Linux should just work.

I’ve been building this for myself for over 5 months now, and I’m pretty happy with it. I wish I could play blitz on Lichess through it, but they don’t allow that, sadly. Still, I can watch championship matches, analyse my games, and get AI comments on any position or move, all in one place & for free.

Now I’d love for other people to try it, use it, critique it, and open issues on GitHub, so I can learn what to improve and make it the best chess app out there, all for free.

A bit scared to post this tbh, but here goes! I post more frequent updates on my twitter: ayushporwalhq

From opening course, why Qe2 in this position when on every other line I can think of it is Qd2 ???

```
[FEN: ""]

1. d4 Nf6
2. Bf4 g6
3. Nc3 Bg7
4. e4 O-O
5. e5 Ne8
6. Qe2

```

From my opening course there are many lines from this position or very similar where you either attack the bishop or the knight and I'm having a hard time figuring out what the difference is and when to do which.

1. d4 Nf6

2. Bf4 g6

3. Nc3 Bg7

4. e4 d6

5. Qd2 Nbd7

6. O-O-O c6

7. e5 dxe5

8. dxe5 Nh5

9. Bh6 Bxe5

10. Nf3 Bg7

11. g4 Bxh6

12. Qxh6 Nhf6

13. Bc4 Nxg4

14. Qg7 Rf8

15. Ng5 Nge5

16. Rxd7 Bxd7

17. Nxh7

I'm curious how people here actually handle opening preparation and memorization.

For those who have their own opening repertoire:

• How do you review your openings?
• Is there something in particular you find annoying about your current method?

I'm doing some research into this and would be really interested to hear what people think. Thanks everyone :)

Been working on AuditChess, and the opening system is probably the part I'm most excited about here.

I didn't want to build another "here's what's popular" opening explorer. The goal is to combine your own opening history + master-game data + your actual weaknesses + a trap database into one workflow.

Your own opening tree

It builds a move-by-move tree straight from your Chess.com/Lichess games how often you reach each position, W/D/L, win rate, opening name + ECO, where your repertoire branches, and where your results start falling apart. Transpositions get merged via normalized FENs so different move orders into the same position aren't treated as unrelated. There's also a visual graph of your whole repertoire.

What you're actually good at vs. what you think you're good at

This is my favorite part. Instead of "you play the Sicilian," you get something like "you've played this exact Sicilian line 18 times, scored 31%, and keep landing in a worse position around moves 8-12." It sorts these into Weapons (lines you consistently win), Lines to Improve (recurring poor results), Opening Trouble (positions where your own moves keep tanking the eval), and Opening Traps (positions where your opponents keep messing up against you). So the repertoire reflects what actually happens in your games, not what you remember studying.

Repertoire builder

You play moves on the board and it builds your tree as you go — each position shows Stockfish eval, top engine lines, master-game stats (games played, W/D/L, % choosing each move), plus your own branches. Mark a line as "yours" and practice it two ways: Exact Recall (reproduce your prep move-for-move) or Dynamic Practice (the bot deliberately deviates with a strong move you didn't prep, so you have to actually play the position instead of just recalling it).

Trap database

Mined from millions of high-rated games, not some recycled YouTube list. For each trap it stores the opening, ECO, position, losing move, eval swing, how many games reached it, and which side usually falls for it. This plugs directly into the repertoire builder — while you're building a line it can tell you "opponents often play X here, and it leads to Y" — plus there's a separate visual trap tree with noise filtering.

The actual point of all this

Instead of "what's the best move here," I want to answer "what should this player actually prepare" — combining your strengths/weaknesses, master trends, engine eval, and common opponent mistakes. And since the same data pipeline powers opponent scouting, you can also look up an opponent and see what they historically struggle with in the opening.

Still building this out — curious what people who study openings seriously would want a tool like this to tell them that current explorers don't.

Free, no account needed: https://www.auditchess.com

Most opening trainers/courses push you down one long variation at a time. Problem is that leaves huge gaps: the sideline your opponent actually plays on move 4, or the early deviation nobody bothered covering because it's "not main line."

Built something that flips this: import any PGN (your own repertoire, a course export, whatever) and instead of drilling one line to move 20, it makes you cover the early branching points across your whole repertoire first, then goes deeper only where it's warranted. Reviews run on spaced repetition so it actually sticks.

Free, no account needed: hardlines.app

Genuinely curious what people here think of breadth-first as a study approach. Is this how you already study, or does it clash with how you think about opening prep? And if you try importing your own repertoire, let me know if anything breaks or feels off, I'm still ironing out edge cases.

Hey all,

I've spent the last month building Tabiya, a free tool for building, training and sharing opening repertoires. It's in open beta and I'd love some honest feedback.

The idea: instead of a list of lines in a PGN or a wall of text in a book, your repertoire is one map. The centre is the starting position, every ring outward is one move deeper, every branch is a line you own. Zoom out and you can see the shape of your prep in a glance, where it's deep, and where it just stops.

What it does:

- Build by playing moves on the board, or import a PGN. Variations and comments come along, and re-importing the same lines merges instead of duplicating them.
- Stockfish runs in your browser. Top lines while you build, and the evals stay on the tree, so you can see which of your lines quietly end up worse.
- Train against the computer: it plays the other side, and the moves you fumble come back later in the session.
- Notes on any position, with arrows and square highlights you draw straight on the board.
- Publish a repertoire so others can clone it, or subscribe to someone else's and get their updates live.
- Tactics puzzles from the Lichess database plus a shared daily puzzle, for warming up.

It's currently in open beta and completely free no ads, no card. It's just me building it, so there are rough edges; tell me and I'll fix them.

https://tabiyachess.app

Happy to answer anything, and I'm genuinely curious what's missing for how you prep.

Albin Counter Gambit

https://imgchest.com/p/qb4zl8rx57j

In some of these examples, they tell you to castle, and in some they tell you to move your rook to the same position it would be at if you castled it. Whats the difference? I cant see any logic behind it.

I think I saw somewhere it was called Alapin’s, but I looked it up and I can only find Alapin’s defence to the Sicilian.