diff --git a/devenv.lock b/devenv.lock
index 119e62f..6ad7695 100644
--- a/devenv.lock
+++ b/devenv.lock
@@ -1,5 +1,57 @@
 {
   "nodes": {
+    "cachix": {
+      "inputs": {
+        "devenv": [
+          "crate2nix"
+        ],
+        "flake-compat": [
+          "crate2nix"
+        ],
+        "git-hooks": "git-hooks",
+        "nixpkgs": "nixpkgs"
+      },
+      "locked": {
+        "lastModified": 1767714506,
+        "narHash": "sha256-WaTs0t1CxhgxbIuvQ97OFhDTVUGd1HA+KzLZUZBhe0s=",
+        "owner": "cachix",
+        "repo": "cachix",
+        "rev": "894c649f0daaa38bbcfb21de64be47dfa7cd0ec9",
+        "type": "github"
+      },
+      "original": {
+        "owner": "cachix",
+        "ref": "latest",
+        "repo": "cachix",
+        "type": "github"
+      }
+    },
+    "crate2nix": {
+      "inputs": {
+        "cachix": "cachix",
+        "devshell": "devshell",
+        "flake-compat": "flake-compat",
+        "flake-parts": "flake-parts",
+        "nix-test-runner": "nix-test-runner",
+        "nixpkgs": [
+          "nixpkgs"
+        ],
+        "pre-commit-hooks": "pre-commit-hooks"
+      },
+      "locked": {
+        "lastModified": 1782759041,
+        "narHash": "sha256-2577vxyoBa8+ZRiXr3CuPtOuEtPRYsFPSZuEc/KI/80=",
+        "owner": "nix-community",
+        "repo": "crate2nix",
+        "rev": "5e1ecfd2d15b34ec90c2e51fdffbe8116595a767",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-community",
+        "repo": "crate2nix",
+        "type": "github"
+      }
+    },
     "devenv": {
       "locked": {
         "dir": "src/modules",
@@ -17,7 +69,42 @@
         "type": "github"
       }
     },
+    "devshell": {
+      "inputs": {
+        "nixpkgs": [
+          "crate2nix",
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1768818222,
+        "narHash": "sha256-460jc0+CZfyaO8+w8JNtlClB2n4ui1RbHfPTLkpwhU8=",
+        "owner": "numtide",
+        "repo": "devshell",
+        "rev": "255a2b1725a20d060f566e4755dbf571bbbb5f76",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "devshell",
+        "type": "github"
+      }
+    },
     "flake-compat": {
+      "locked": {
+        "lastModified": 1733328505,
+        "narHash": "sha256-NeCCThCEP3eCl2l/+27kNNK7QrwZB1IJCrXfrbv5oqU=",
+        "rev": "ff81ac966bb2cae68946d5ed5fc4994f96d0ffec",
+        "revCount": 69,
+        "type": "tarball",
+        "url": "https://api.flakehub.com/f/pinned/edolstra/flake-compat/1.1.0/01948eb7-9cba-704f-bbf3-3fa956735b52/source.tar.gz"
+      },
+      "original": {
+        "type": "tarball",
+        "url": "https://flakehub.com/f/edolstra/flake-compat/1.tar.gz"
+      }
+    },
+    "flake-compat_2": {
       "flake": false,
       "locked": {
         "lastModified": 1767039857,
@@ -33,9 +120,58 @@
         "type": "github"
       }
     },
+    "flake-parts": {
+      "inputs": {
+        "nixpkgs-lib": [
+          "crate2nix",
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1768135262,
+        "narHash": "sha256-PVvu7OqHBGWN16zSi6tEmPwwHQ4rLPU9Plvs8/1TUBY=",
+        "owner": "hercules-ci",
+        "repo": "flake-parts",
+        "rev": "80daad04eddbbf5a4d883996a73f3f542fa437ac",
+        "type": "github"
+      },
+      "original": {
+        "owner": "hercules-ci",
+        "repo": "flake-parts",
+        "type": "github"
+      }
+    },
     "git-hooks": {
       "inputs": {
-        "flake-compat": "flake-compat",
+        "flake-compat": [
+          "crate2nix",
+          "cachix",
+          "flake-compat"
+        ],
+        "gitignore": "gitignore",
+        "nixpkgs": [
+          "crate2nix",
+          "cachix",
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1765404074,
+        "narHash": "sha256-+ZDU2d+vzWkEJiqprvV5PR26DVFN2vgddwG5SnPZcUM=",
+        "owner": "cachix",
+        "repo": "git-hooks.nix",
+        "rev": "2d6f58930fbcd82f6f9fd59fb6d13e37684ca529",
+        "type": "github"
+      },
+      "original": {
+        "owner": "cachix",
+        "repo": "git-hooks.nix",
+        "type": "github"
+      }
+    },
+    "git-hooks_2": {
+      "inputs": {
+        "flake-compat": "flake-compat_2",
         "nixpkgs": [
           "nixpkgs"
         ]
@@ -54,22 +190,80 @@
         "type": "github"
       }
     },
-    "nixpkgs": {
+    "gitignore": {
       "inputs": {
-        "nixpkgs-src": "nixpkgs-src"
+        "nixpkgs": [
+          "crate2nix",
+          "cachix",
+          "git-hooks",
+          "nixpkgs"
+        ]
       },
       "locked": {
-        "lastModified": 1782924808,
-        "narHash": "sha256-tn2ahNv3ZNXyVHdPx/uw+N0xa7YSMtXUr6OEvu+s8ng=",
-        "owner": "cachix",
-        "repo": "devenv-nixpkgs",
-        "rev": "e2c881cb8d5f1cac6cef9d71f0d450a55691b999",
+        "lastModified": 1709087332,
+        "narHash": "sha256-HG2cCnktfHsKV0s4XW83gU3F57gaTljL9KNSuG6bnQs=",
+        "owner": "hercules-ci",
+        "repo": "gitignore.nix",
+        "rev": "637db329424fd7e46cf4185293b9cc8c88c95394",
         "type": "github"
       },
       "original": {
-        "owner": "cachix",
-        "ref": "rolling",
-        "repo": "devenv-nixpkgs",
+        "owner": "hercules-ci",
+        "repo": "gitignore.nix",
+        "type": "github"
+      }
+    },
+    "gitignore_2": {
+      "inputs": {
+        "nixpkgs": [
+          "crate2nix",
+          "pre-commit-hooks",
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1709087332,
+        "narHash": "sha256-HG2cCnktfHsKV0s4XW83gU3F57gaTljL9KNSuG6bnQs=",
+        "owner": "hercules-ci",
+        "repo": "gitignore.nix",
+        "rev": "637db329424fd7e46cf4185293b9cc8c88c95394",
+        "type": "github"
+      },
+      "original": {
+        "owner": "hercules-ci",
+        "repo": "gitignore.nix",
+        "type": "github"
+      }
+    },
+    "nix-test-runner": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1588761593,
+        "narHash": "sha256-FKJykltAN/g3eIceJl4SfDnnyuH2jHImhMrXS2KvGIs=",
+        "owner": "stoeffel",
+        "repo": "nix-test-runner",
+        "rev": "c45d45b11ecef3eb9d834c3b6304c05c49b06ca2",
+        "type": "github"
+      },
+      "original": {
+        "owner": "stoeffel",
+        "repo": "nix-test-runner",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1765186076,
+        "narHash": "sha256-hM20uyap1a0M9d344I692r+ik4gTMyj60cQWO+hAYP8=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "addf7cf5f383a3101ecfba091b98d0a1263dc9b8",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
         "type": "github"
       }
     },
@@ -90,11 +284,57 @@
         "type": "github"
       }
     },
+    "nixpkgs_2": {
+      "inputs": {
+        "nixpkgs-src": "nixpkgs-src"
+      },
+      "locked": {
+        "lastModified": 1782924808,
+        "narHash": "sha256-tn2ahNv3ZNXyVHdPx/uw+N0xa7YSMtXUr6OEvu+s8ng=",
+        "owner": "cachix",
+        "repo": "devenv-nixpkgs",
+        "rev": "e2c881cb8d5f1cac6cef9d71f0d450a55691b999",
+        "type": "github"
+      },
+      "original": {
+        "owner": "cachix",
+        "ref": "rolling",
+        "repo": "devenv-nixpkgs",
+        "type": "github"
+      }
+    },
+    "pre-commit-hooks": {
+      "inputs": {
+        "flake-compat": [
+          "crate2nix",
+          "flake-compat"
+        ],
+        "gitignore": "gitignore_2",
+        "nixpkgs": [
+          "crate2nix",
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1769069492,
+        "narHash": "sha256-Efs3VUPelRduf3PpfPP2ovEB4CXT7vHf8W+xc49RL/U=",
+        "owner": "cachix",
+        "repo": "pre-commit-hooks.nix",
+        "rev": "a1ef738813b15cf8ec759bdff5761b027e3e1d23",
+        "type": "github"
+      },
+      "original": {
+        "owner": "cachix",
+        "repo": "pre-commit-hooks.nix",
+        "type": "github"
+      }
+    },
     "root": {
       "inputs": {
+        "crate2nix": "crate2nix",
         "devenv": "devenv",
-        "git-hooks": "git-hooks",
-        "nixpkgs": "nixpkgs",
+        "git-hooks": "git-hooks_2",
+        "nixpkgs": "nixpkgs_2",
         "treefmt-nix": "treefmt-nix"
       }
     },
diff --git a/devenv.nix b/devenv.nix
index 3eb4308..a63f4c5 100644
--- a/devenv.nix
+++ b/devenv.nix
@@ -6,6 +6,30 @@
   ...
 }:
 
+let
+  # devenv's `languages.rust.import` only builds single root-package crates
+  # (it hardcodes `cargoNix.rootCrate.build`). tora is a virtual workspace with
+  # no root package, so we drive crate2nix directly and select the `torad` member
+  # out of `workspaceMembers`. src = ./. gives crate2nix the whole workspace, so
+  # torad's path-dependency on ../proto (tora-proto) resolves.
+  crate2nixTools = pkgs.callPackage "${inputs.crate2nix}/tools.nix" { };
+  cargoNix =
+    pkgs.callPackage
+      (crate2nixTools.generatedCargoNix {
+        name = "tora";
+        src = ./.;
+      })
+      {
+        # Build with the toolchain configured for this dev environment,
+        # matching what languages.rust.import does internally.
+        buildRustCrateForPkgs =
+          _:
+          pkgs.buildRustCrate.override {
+            rustc = config.languages.rust.toolchainPackage;
+            cargo = config.languages.rust.toolchainPackage;
+          };
+      };
+in
 {
   languages.rust.enable = true;
   git-hooks.hooks = {
@@ -57,13 +81,13 @@
 
   processes.torad = {
     exec = ''
-      cargo run -p torad -- --socket "$TORAD_SOCKET" --pid-file "$TORAD_PID_FILE"
+      ${config.outputs.torad}/bin/torad --socket "$TORAD_SOCKET" --pid-file "$TORAD_PID_FILE"
     '';
     # Waits for postgres's own readiness probe (pg_isready + SELECT 1), not just process start.
     after = [ "devenv:processes:postgres" ];
   };
 
   outputs = {
-    tora = config.languages.rust.import ./. { };
+    torad = cargoNix.workspaceMembers.torad.build;
   };
 }
diff --git a/devenv.yaml b/devenv.yaml
index ee5a179..528758b 100644
--- a/devenv.yaml
+++ b/devenv.yaml
@@ -1,4 +1,9 @@
 inputs:
+  crate2nix:
+    url: github:nix-community/crate2nix
+    inputs:
+      nixpkgs:
+        follows: nixpkgs
   git-hooks:
     url: github:cachix/git-hooks.nix
     inputs: