diff --git a/.gitignore b/.gitignore
index 3ff1697..400857f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -18,3 +18,5 @@ Eldev-local
 
 # OS
 .DS_Store
+/.envrc
+/.direnv/
diff --git a/flake.lock b/flake.lock
new file mode 100644
index 0000000..3fa3b42
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,240 @@
+{
+  "nodes": {
+    "blueprint": {
+      "inputs": {
+        "nixpkgs": [
+          "jailed-agents",
+          "llm-agents",
+          "nixpkgs"
+        ],
+        "systems": "systems_3"
+      },
+      "locked": {
+        "lastModified": 1769353768,
+        "narHash": "sha256-zI+7cbMI4wMIR57jMjDSEsVb3grapTnURDxxJPYFIW0=",
+        "owner": "numtide",
+        "repo": "blueprint",
+        "rev": "c7da5c70ad1c9b60b6f5d4f674fbe205d48d8f6c",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "blueprint",
+        "type": "github"
+      }
+    },
+    "flake-utils": {
+      "inputs": {
+        "systems": "systems"
+      },
+      "locked": {
+        "lastModified": 1731533236,
+        "narHash": "sha256-l0KFg5HjrsfsO/JpG+r7fRrqm12kzFHyUHqHCVpMMbI=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "11707dc2f618dd54ca8739b309ec4fc024de578b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "flake-utils_2": {
+      "inputs": {
+        "systems": "systems_2"
+      },
+      "locked": {
+        "lastModified": 1731533236,
+        "narHash": "sha256-l0KFg5HjrsfsO/JpG+r7fRrqm12kzFHyUHqHCVpMMbI=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "11707dc2f618dd54ca8739b309ec4fc024de578b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "jail-nix": {
+      "locked": {
+        "lastModified": 1765903853,
+        "narHash": "sha256-buoPpx7moJzAXbLuHAImn6x9fGRdk3x0T57goPv1vnc=",
+        "owner": "~alexdavid",
+        "repo": "jail.nix",
+        "rev": "bf9f49c8118e7a77b68a675dbe26e93e91412066",
+        "type": "sourcehut"
+      },
+      "original": {
+        "owner": "~alexdavid",
+        "repo": "jail.nix",
+        "type": "sourcehut"
+      }
+    },
+    "jailed-agents": {
+      "inputs": {
+        "flake-utils": "flake-utils_2",
+        "jail-nix": "jail-nix",
+        "llm-agents": "llm-agents",
+        "nixpkgs": "nixpkgs_2"
+      },
+      "locked": {
+        "lastModified": 1769818307,
+        "narHash": "sha256-FjojfnmW2/jRmbxfk+8yzU9OfqIl1mClNLywzSujSKQ=",
+        "path": "/conf/jailed-agents",
+        "type": "path"
+      },
+      "original": {
+        "path": "/conf/jailed-agents",
+        "type": "path"
+      }
+    },
+    "llm-agents": {
+      "inputs": {
+        "blueprint": "blueprint",
+        "nixpkgs": "nixpkgs",
+        "treefmt-nix": "treefmt-nix"
+      },
+      "locked": {
+        "lastModified": 1769813338,
+        "narHash": "sha256-IlRKon8+bfoi/uOa8CUPAAWW0Pv6AHBSF1jVSD4QO8U=",
+        "owner": "numtide",
+        "repo": "llm-agents.nix",
+        "rev": "58939415e56d01c30d429cf0c49a9d8e2a6a07c3",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "llm-agents.nix",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1769740369,
+        "narHash": "sha256-xKPyJoMoXfXpDM5DFDZDsi9PHArf2k5BJjvReYXoFpM=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "6308c3b21396534d8aaeac46179c14c439a89b8a",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixpkgs-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs_2": {
+      "locked": {
+        "lastModified": 1769461804,
+        "narHash": "sha256-msG8SU5WsBUfVVa/9RPLaymvi5bI8edTavbIq3vRlhI=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "bfc1b8a4574108ceef22f02bafcf6611380c100d",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs_3": {
+      "locked": {
+        "lastModified": 1769789167,
+        "narHash": "sha256-kKB3bqYJU5nzYeIROI82Ef9VtTbu4uA3YydSk/Bioa8=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "62c8382960464ceb98ea593cb8321a2cf8f9e3e5",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "jailed-agents": "jailed-agents",
+        "nixpkgs": "nixpkgs_3"
+      }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    },
+    "systems_2": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    },
+    "systems_3": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    },
+    "treefmt-nix": {
+      "inputs": {
+        "nixpkgs": [
+          "jailed-agents",
+          "llm-agents",
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1769691507,
+        "narHash": "sha256-8aAYwyVzSSwIhP2glDhw/G0i5+wOrren3v6WmxkVonM=",
+        "owner": "numtide",
+        "repo": "treefmt-nix",
+        "rev": "28b19c5844cc6e2257801d43f2772a4b4c050a1b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "treefmt-nix",
+        "type": "github"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/flake.nix b/flake.nix
new file mode 100644
index 0000000..0579f25
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,61 @@
+{
+  description = "Emacs mode development environment";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+    jailed-agents.url = "path:/conf/jailed-agents";
+  };
+
+  outputs =
+    { self, nixpkgs, flake-utils, jailed-agents, ... }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+
+        # Choose your Emacs build (e.g., pkgs.emacs, pkgs.emacs-nox, pkgs.emacs-pgtk)
+        epkgs = pkgs.emacsPackagesFor pkgs.emacs;
+
+        # Emacs wrapped with useful dev/test/lint packages available in load-path
+        emacsWithDeps = epkgs.emacsWithPackages (p: with p; [
+          package-lint
+          relint
+          buttercup
+        ]);
+
+        devInputs = with pkgs; [
+          emacsWithDeps
+          epkgs.eldev
+          git
+          gnumake
+          texinfo
+          ripgrep
+        ];
+      in
+      {
+        devShells.default = pkgs.mkShell {
+          packages = devInputs ++ [
+            (jailed-agents.lib.${system}.makeJailedOpencode system {
+              extraPkgs = devInputs;
+            })
+          ];
+
+          shellHook = ''
+            echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+            echo "  Emacs Mode Development Environment"
+            echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+            echo ""
+            echo "Common tasks:"
+            echo "  eldev lint        # package-lint + relint"
+            echo "  eldev test        # run ERT/Buttercup tests"
+            echo "  eldev compile     # byte-compile"
+            echo "  eldev package     # build release tarball"
+            echo ""
+            echo "Start Emacs (preconfigured load-path):"
+            echo "  emacs ."
+            echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+          '';
+        };
+      }
+    );
+}