NixShell + direnv + Emacs

Has anybody successfully tried using nixshell + direnv + emacs ? essentially I would like emacs to work within a nixshell whenever I open a buffer in a particular project. i.e: use pythonenv in nixshell. Has anybody tried anything similar? thanks

Have you tried using `nix-buffer`? I manage my emacs packages using `home-manager`, and use `nix-buffer` as and when needed.

I have this but for flakes and it works perfectly. If you haven't found it yet use [emacs-direnv](https://github.com/wbolster/emacs-direnv). It will automatically switch the environment when changing directories. If I change something in a flake, I need to use the `direnv-update-directory-enviornment` to get it to change but other than that just change buffers and it will figure out if you're in a new directory environment or not. Using this I can run a project specific python (or whatever language) repl in emacs. For example, I don't actually have python installed globally, so if I try to run `run-python` somewhere, I get the error "start-process: Searching for program: No such file or directory, ipython" but open a flake with python as a dependency and I can start the python repl.

I am currently using [envrc](https://github.com/purcell/envrc) by Purcell, and it works like a charm. I was previously using direnv-mode, which should also work. I use flakes, so 1. Add dependencies to `buildInputs` of `devShell` (`devShells.default` since Nix 2.7) in flake.nix 2. Open vterm and run `nix develop` to fetch the dependencies 3. Create .envrc with `use flake` as its content 4. `envrc-allow` Similar steps would work for `shell.nix`. If you don't use a flake, `.envrc` should contain `use nix`.

I'm using [lorri](https://github.com/nix-community/lorri) and [emacs-direnv](https://github.com/wbolster/emacs-direnv) together, works perfectly fine for me.

{ description = "Make me a github Melpa project yesterday!"; # inputs are pinned via flake.lock. The normal way to update an individual # version is: # nix flake lock --update-input emacs-overlay # Tracking can be accomplished via CI and machine commits inputs = { # stable branches are recommended for CI, regression spotting. Testing with # multiple versions can be done via input overrides, such as: # nix build .#ci --override-input nixpkgs github:nixpkgs/nixpkgs/unstable nixpkgs.url = "github:nixos/nixpkgs?ref=release-22.05"; flake-utils.url = "github:numtide/flake-utils"; emacs-overlay.url = "github:nix-community/emacs-overlay"; # slave Emacs overlay to our nixpkgs. This doesn't do a lot except reduce # the closure size and allow us to control both nixpkgs versions with one # declaration. emacs-overlay.inputs.nixpkgs.follows = "nixpkgs"; emacs-overlay.inputs.flake-utils.follows = "flake-utils"; }; outputs = inputs: with inputs; flake-utils.lib.eachDefaultSystem (system: let pkgs = import nixpkgs { inherit system; overlays = [ emacs-overlay.overlay ]; }; runTestsShell = pkgs.mkShell { packages = [ pkgs.emacsNativeComp ]; }; in { # The output set, where all useful things go. If your nix flake exposes # packages, overlays, shells, or nix utils, they can be exposed here for # downstream consumption. devShells = { default = runTestsShell; }; }); } Contents of .envrc are `use nix` and it automagically loads the `devShells.default`