Things I miss (a lot!) in Lem

[svetlyak40wt]

Today I've tried to use Lem for work on one of my pet projects. Here is the list of things I was lacking to be productive:

Table of Contents

1. Things I miss (a lot!) in Lem
   1. (ADDED) A ChangeLog.md
   2. Bindings
      1. (DONE) C-c ~ (or C-c v) repl-sync to syncronize current package
      2. (DONE) C-w to delete previous word
      3. (DONE) Undo is not bound to C-/
      4. (DONE) Paredit should indent line after the new-line
      5. (DONE) Something like C-u C-Space or pop-global-mark
      6. (partial) C-s C-w - to search thing a point
      7. (DONE) Double C-s should start searching a previous term
      8. (OK) C-c x to export symbol at point (as in SLY)
   3. Gotchas
      1. Unable to start Lem's lisp repl when you already connected to other Lisp process and have a REPL
      2. (DONE) Lisp-mode should kee history between restarts
      3. (DONE) Grep should search in the whole project
      4. C-u C-c C-c should compile defun with (optimize (debug 3) (safety 3) (speed 0))
   4. Modes
      1. (MERGED) Package Manager
      2. (PARTIAL) Lispy-mode
      3. (third-party) Bookmarks
      4. (STARTED) Org-Mode
      5. (STARTED) Magit
      6. Helm
      7. (OK) Projectile (with helm integration)
      8. (STARTED) YaSnippet

Things I miss (a lot!) in Lem

A ChangeLog.md

The changelog file is back (as of 2026-04-24).

Bindings

DONE C-c ~ (or C-c v) repl-sync to syncronize current package

• State "DONE" from [2024-07-24]

DONE C-w to delete previous word

• State "DONE" from [2019-08-26 Mon 09:27]

(Can be bound to backward-delete-word

DONE Undo is not bound to C-/

• State "DONE" from [2019-08-26 Mon 19:54]

(DONE) Paredit should indent line after the new-line

• DONE

(DONE) Something like C-u C-Space or pop-global-mark

• DONE: use C-space and C-x C-x exchange-point-mark, see Implement mark-ring #1785

to jump to the previous place where cusor was. Like bm-toggle function
from Gnu Emacs.

With prefix argument (e.g., \\[universal-argument] \\[set-mark-command]), \
jump to the mark, and set the mark from
position popped off the local mark ring (this does not affect the global
mark ring). Use \\[pop-global-mark] to jump to a mark popped off the global
mark ring (see `pop-global-mark').

(partial) C-s C-w - to search thing a point

There is a function isearch-forward-symbol-at-point

(edit: vi-mode has * and # that do exactly that)

(DONE) Double C-s should start searching a previous term

• DONE

(OK) C-c x to export symbol at point (as in SLY)

• DONE 90%: there is the command M-x lisp-add-export.

Gotchas

Unable to start Lem's lisp repl when you already connected to other Lisp process and have a REPL

(DONE) Lisp-mode should keep history between restarts

Probably…

• DONE

(DONE) Grep should search in the whole project

I don't know where it searches, but only not in my project's root :(

Should work like helm-projectile-ag or helm-projectile-grep.

• DONE: there is now M-x project-grep bound to C-x p g.

C-u C-c C-c should compile defun with (optimize (debug 3) (safety 3) (speed 0))

Modes

(MERGED) Package Manager

• merged: https://github.com/lem-project/lem-extension-manager/

Lispy-mode

started: https://github.com/40ants/lem-pareto

(third-party) Bookmarks

• see https://github.com/mychris/lem-bookmark

(STARTED) Org-Mode

• it's brewing…

• 2025, August: organ-mode does: highlighting, (fast) parsing, viewing org-agenda todos, export to LaTeX. In early development.

(STARTED) Magit

• lem-legit: https://github.com/lem-project/lem/blob/main/extensions/legit/README.md M-x legit-status

Helm

(OK) Projectile (with helm integration)

• project-aware commands were added (no special "helm integration")

(STARTED) YaSnippet

[svetlyak40wt]

I hope these things will be solved someday. We should do a lot of work to make Lem a really feature full IDE for CL.

If somebody has his own list of "missing features", I'd like to learn about them.

[snmsts]

What do you mean by package manager?

[svetlyak40wt]

What do you mean by package manager?

I mean a way to discover and install third-party extesions (modes). Something like Gnu Emacs's M-x list-packages.

For example, I want to port a lispy-mode to lem. What do I need to to to make it available to all other Lem's users?

[svetlyak40wt]

Implemented a subset of the Lispy's functionality in the Pareto mode.

[svetlyak40wt]

By the way, probably, the package manager can use Ultralisp's API, to list all systems, tagged as lem. However, the tagging should be added to the Ultralisp.org first.

[vindarel]

Projectile

A few project-related commands were added 🚀

https://lem-project.github.io/lem-page/usage/usage/#find-file-in-project

M-x project-find-file

with auto-completion of a shrinking list, not far from Helm.

M-x project-delete-buffers, project-directory

C-x d (M-x filer) opens a tree view on the left at the project root

We can fix grep to search on the project root.

under src/commands/project.lisp.

---

edit: M-x project-switch was added (C-x p p).

[rajcspsg]

treemacs, centaur tabs

[vindarel]

treemacs

There's M-x filer (C-x d) added after Lem 2.0, a project file viewer (not managing many projects).

https://lem-project.github.io/lem-page/usage/usage/#filer

(Sure it's simpler, the base is here)

tabs

(edit) with the comment below I learned about tabs: M-x toggle-tabbar.

[Sasanidas]

treemacs, centaur tabs

There are tabs already, but not as polish as centaur tabs 👍

[vindarel]

Magit

A Magit-like interface was added: https://github.com/lem-project/lem/blob/main/extensions/legit/README.md

M-x legit-status

presentation and implementation details: https://lisp-journey.gitlab.io/blog/oh-no-i-started-a-magit-like-plugin-for-the-lem-editor/

[vindarel]

yasnipet

not dissimilar: inserting templates #1282