New: Julia for JetBrains IDEs (Flexible Julia)

New Release: Flexible Julia 2026.9.11

New Features:

  • Hot-Swap Debugger: Swap out functions while paused at a breakpoint - changes take effect immediately
  • DAP hot-reload now attempts frame reconstruction so the current paused frame uses the new code right away
  • Tab-iterable variable placeholders in postfix templates .for, .if, .while, .try

Fixes:

  • External package symbols from using fully resolved in undefined variable inspection (#85)
  • Type names in isa and :: expressions no longer flagged as undefined variables (#85)
  • Postfix templates (.for, .if, .while) no longer malformed when expression ends with ) or ] (#88)
  • Quote auto-closing now works for " and ' (#89)

HOT-SWAPPING IS HERE!
This actually took me a lot longer to implement, cause I had to hack my way around frame modification, but now we got hot-swapping support. I got inspired by Julia debugging is extremely slow - #12 by tue, and even though it is not perfect, it is perhaps a step in the right direction.

So here’s what it does: You can now edit a function while paused at a breakpoint and have it take effect immediately - no need to restart your debug session. The DAP layer even tries to reconstruct the current frame so you’re running the new code right away. This means, you can start a debug session (either in REPL or native JetBrains), set a breakpoint and modify the sources. The debugger will update with you. You can see it working in the video in my post above.

This should make the edit-debug cycle a lot faster, especially when you’re tracking down those bugs that only show up after a long warmup.

Apart from that, I also added a few fixes to the validator and some convenience features.


@tue: for sharing your problems with “debugging in julia”
@ufechner7: Thanks for the follow-up on external package symbol recognition!
@SamuelMathieu-code: Appreciate the reports on postfix templates and editor usability - all fixed!


The new release is already available in the beta channel and you can expect JetBrains to approve it today or early tomorrow.

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