fix bug

.github/workflows/diff-pr.yml

@@ -13,21 +13,26 @@ concurrency:
 
 jobs:
   dix:
-    runs-on: nix
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
         with:
           fetch-depth: 0
 
+      - uses: cachix/install-nix-action@v31
+        with:
+          extra_nix_config: |
+            experimental-features = nix-command flakes
+
       - name: worktree base for diff
         run: git worktree add "$RUNNER_TEMP/base" "${{ github.event.pull_request.base.sha }}"
 
       - name: build closures and render diff
         run: |
-          nix run -L .#ci -- diff "$RUNNER_TEMP/base" . \
+          nix run .#ci -- diff "$RUNNER_TEMP/base" . \
             "### System closure diff vs \`${{ github.event.pull_request.base.ref }}\`" \
             > "$RUNNER_TEMP/comment.md"
-          nix run -L .#ci -- inspect-diff "$RUNNER_TEMP/base" . \
+          nix run .#ci -- inspect-diff "$RUNNER_TEMP/base" . \
             "### Inspection diff vs \`${{ github.event.pull_request.base.ref }}\`" \
             >> "$RUNNER_TEMP/comment.md"
 
@@ -37,4 +42,4 @@ jobs:
           API: ${{ github.api_url }}
           REPO: ${{ github.repository }}
           PR: ${{ github.event.pull_request.number }}
-        run: nix run -L .#ci -- post-comment "<!-- dix-diff -->" "$RUNNER_TEMP/comment.md"
+        run: nix run .#ci -- post-comment "<!-- dix-diff -->" "$RUNNER_TEMP/comment.md"

.github/workflows/diff-tag.yml

@@ -9,12 +9,17 @@ permissions:
 
 jobs:
   dix:
-    runs-on: nix
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
         with:
           fetch-depth: 0
 
+      - uses: cachix/install-nix-action@v31
+        with:
+          extra_nix_config: |
+            experimental-features = nix-command flakes
+
       - name: diff latest tag against HEAD
         run: |
           tag=$(git tag --sort=-creatordate | head -n1)
@@ -25,8 +30,8 @@ jobs:
           git worktree add "$RUNNER_TEMP/old" "$tag"
           head=$(git rev-parse --short HEAD)
           {
-            nix run -L .#ci -- diff "$RUNNER_TEMP/old" . \
+            nix run .#ci -- diff "$RUNNER_TEMP/old" . \
               "# System closure diff: \`$tag\` -> \`$head\`"
-            nix run -L .#ci -- inspect-diff "$RUNNER_TEMP/old" . \
+            nix run .#ci -- inspect-diff "$RUNNER_TEMP/old" . \
               "# Inspection diff: \`$tag\` -> \`$head\`"
           } | tee -a "$GITHUB_STEP_SUMMARY"

.github/workflows/flake-check.yml

@@ -14,8 +14,13 @@ concurrency:
 
 jobs:
   flake-check:
-    runs-on: nix
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
 
+      - uses: cachix/install-nix-action@v31
+        with:
+          extra_nix_config: |
+            experimental-features = nix-command flakes
+
       - run: nix flake check -L

.github/workflows/flake-update.yml

@@ -11,11 +11,16 @@ permissions:
 
 jobs:
   update:
-    runs-on: nix
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
 
-      - run: nix flake update -L
+      - uses: cachix/install-nix-action@v31
+        with:
+          extra_nix_config: |
+            experimental-features = nix-command flakes
+
+      - run: nix flake update
 
       - name: open/update PR
         env:
@@ -24,5 +29,5 @@ jobs:
           REPO: ${{ github.repository }}
         run: |
           printf 'Automated `nix flake update`.\n' > "$RUNNER_TEMP/body.md"
-          nix run -L .#ci -- open-pr \
+          nix run .#ci -- open-pr \
             flake-update "$GITHUB_REF_NAME" "flake.lock: update inputs" "$RUNNER_TEMP/body.md" automated

.github/workflows/lint.yml

@@ -15,22 +15,27 @@ concurrency:
 
 jobs:
   lint:
-    runs-on: nix
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
 
-      - name: run linters
+      - uses: cachix/install-nix-action@v31
-        run: nix run -L .#ci -- lint . "$RUNNER_TEMP/findings"
+        with:
+          extra_nix_config: |
+            experimental-features = nix-command flakes
 
-      - name: report findings
+      - name: pick reporter
-        if: always()
-        env:
-          REVIEWDOG_GITEA_API_TOKEN: ${{ secrets.GITEA_TOKEN }}
-          GITEA_ADDRESS: ${{ github.server_url }}
         run: |
           if [ "${{ github.event_name }}" = pull_request ]; then
-            nix run -L .#ci -- lint-report gitea-pr-review "$RUNNER_TEMP/findings"
+            echo "REPORTER=github-pr-review" >> "$GITHUB_ENV"
           else
-            nix run -L .#ci -- lint-summary "$RUNNER_TEMP/findings" \
+            echo "REPORTER=local" >> "$GITHUB_ENV"
-              | tee -a "$GITHUB_STEP_SUMMARY"
           fi
+
+      - name: run linters
+        run: nix run .#ci -- lint . "$RUNNER_TEMP/findings"
+
+      - name: report findings
+        env:
+          REVIEWDOG_GITHUB_API_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: nix run .#ci -- lint-report "$REPORTER" "$RUNNER_TEMP/findings"

.github/workflows/vulnix.yml

@@ -11,13 +11,18 @@ permissions:
 
 jobs:
   scan:
-    runs-on: nix
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
 
+      - uses: cachix/install-nix-action@v31
+        with:
+          extra_nix_config: |
+            experimental-features = nix-command flakes
+
       - name: scan host closures
         id: scan
-        run: echo "count=$(nix run -L .#ci -- vulnix . "$RUNNER_TEMP/issue.md")" >> "$GITHUB_OUTPUT"
+        run: echo "count=$(nix run .#ci -- vulnix . "$RUNNER_TEMP/issue.md")" >> "$GITHUB_OUTPUT"
 
       - name: file/update issue
         if: steps.scan.outputs.count != '0'
@@ -25,7 +30,7 @@ jobs:
           GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           API: ${{ github.api_url }}
           REPO: ${{ github.repository }}
-        run: 'nix run -L .#ci -- upsert-issue vulnix "vulnix: known vulnerabilities in system closure" "$RUNNER_TEMP/issue.md"'
+        run: nix run .#ci -- upsert-issue vulnix "vulnix: known vulnerabilities in system closure" "$RUNNER_TEMP/issue.md"
 
       - name: close resolved issue
         if: steps.scan.outputs.count == '0'
@@ -33,4 +38,4 @@ jobs:
           GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           API: ${{ github.api_url }}
           REPO: ${{ github.repository }}
-        run: nix run -L .#ci -- close-issue vulnix
+        run: nix run .#ci -- close-issue vulnix

ci.nix

@@ -1,17 +1,9 @@
 { lib, pkgs }:
-let
-  # vulnix's bundled nix-2.34 broke its own --experimental-features detection
-  nixConf = pkgs.writeText "ci-nix.conf" "experimental-features = nix-command flakes";
-in
 # tools must track ci.py's subprocess calls; nix stays ambient (uses the
 # runner's own nix, not a pinned one).
 pkgs.writers.writePython3Bin "ci" {
   flakeIgnore = [ "E501" ];
-  libraries = [ pkgs.python3Packages.subprocess-tee ];
   makeWrapperArgs = [
-    "--set-default"
-    "NIX_USER_CONF_FILES"
-    (toString nixConf)
     "--prefix"
     "PATH"
     ":"

ci.py

@@ -6,7 +6,6 @@ import json
 import os
 import re
 import subprocess
-import subprocess_tee
 import sys
 import urllib.request
 from collections import Counter
@@ -18,8 +17,7 @@ def run(*args, **kw):
 
 
 def nix(*args):
-    # tee to stderr - stdout leaks into GITHUB_OUTPUT $() captures
+    return run("nix", "--extra-experimental-features", "nix-command flakes", *args, check=True, capture_output=True).stdout
-    return subprocess_tee.run(("nix", "--extra-experimental-features", "nix-command flakes", "-L", *args), check=True, text=True, stdout=sys.stderr).stdout
 
 
 def git(*args, check=True):
@@ -364,63 +362,10 @@ def lint_report(args):
 
     codes = [reviewdog(f"{args.dir}/{name}", flags)
              for name, flags in LINTERS
-             if os.path.isfile(f"{args.dir}/{name}") and os.path.getsize(f"{args.dir}/{name}") > 0]
+             if os.path.getsize(f"{args.dir}/{name}") > 0]
     sys.exit(1 if any(codes) else 0)
 
 
-def has_findings(path):
-    return os.path.isfile(path) and os.path.getsize(path) > 0
-
-
-def fmt_rdjsonl(path):
-    lines = []
-    with open(path) as f:
-        for raw in f:
-            rec = json.loads(raw)
-            loc = rec["location"]
-            r = loc.get("range", {}).get("start")
-            pos = f"{loc['path']}:{r['line']}:{r['column']}" if r else loc["path"]
-            lines.append(f"- `{pos}`: {rec['message']}")
-    return "\n".join(lines)
-
-
-def fmt_errfmt(path):
-    lines = []
-    with open(path) as f:
-        for raw in f:
-            parts = raw.strip().split(">", 1)
-            if len(parts) == 2:
-                lines.append(f"- `{parts[0]}:{parts[1].split(':', 3)[-1].strip()}`" if ":" in parts[1] else f"- `{raw.strip()}`")
-            elif raw.strip():
-                lines.append(f"- `{raw.strip()}`")
-    return "\n".join(lines)
-
-
-def lint_summary(args):
-    sections = []
-    d = args.dir
-
-    if has_findings(f"{d}/nixfmt.diff"):
-        with open(f"{d}/nixfmt.diff") as f:
-            sections.append(f"## nixfmt\n\n```diff\n{f.read().rstrip()}\n```")
-
-    if has_findings(f"{d}/statix.errfmt"):
-        sections.append(f"## statix\n\n{fmt_errfmt(f'{d}/statix.errfmt')}")
-
-    if has_findings(f"{d}/deadnix.rdjsonl"):
-        sections.append(f"## deadnix\n\n{fmt_rdjsonl(f'{d}/deadnix.rdjsonl')}")
-
-    if has_findings(f"{d}/cycles.rdjsonl"):
-        sections.append(f"## systemd ordering cycles\n\n{fmt_rdjsonl(f'{d}/cycles.rdjsonl')}")
-
-    if sections:
-        print("\n\n".join(["# Lint findings"] + sections))
-        sys.exit(1)
-    else:
-        print("No lint findings.")
-        sys.exit(0)
-
-
 def post_comment(args):
     body = args.marker + "\n" + Path(args.body_file).read_text()
     pr = os.environ["PR"]
@@ -493,7 +438,6 @@ def main():
     command("vulnix", vulnix, "ref", "body_out")
     command("lint", lint, "target", "out")
     command("lint-report", lint_report, "reporter", "dir")
-    command("lint-summary", lint_summary, "dir")
     command("post-comment", post_comment, "marker", "body_file")
     command("upsert-issue", upsert_issue, "label", "title", "body_file")
     command("close-issue", close_issue, "label")

containers/common/overseer.nix

@@ -381,6 +381,6 @@ let
         };
       };
     };
-  inherit (c) hostAddr;
+  hostAddr = c.hostAddr;
 in
 c

containers/server-n0/git.nix

@@ -8,9 +8,6 @@ let
   inherit (dsl) mkContainer mkVm;
   inherit (hostInfo.paths) data secrets;
 
-  pubSshPort = 23;
-  intSshPort = 23 + 8000;
-
   ciRunnerData = "${data}/web/git-ci-runner";
   ciRunnerSecrets = "${secrets}/ci-runner";
 in
@@ -20,8 +17,8 @@ in
     net.access = [ { to = "@internet"; } ];
     net.forward.tcp = [
       {
-        host = pubSshPort;
+        host = 23;
-        container = intSshPort;
+        container = 8023;
       }
     ];
     svc.autoStart = true;
@@ -41,8 +38,7 @@ in
             ROOT_URL = "https://git.floweytf.com/";
             START_SSH_SERVER = true;
             BUILTIN_SSH_SERVER_USER = "git";
-            SSH_PORT = pubSshPort;
+            SSH_PORT = 8023;
-            SSH_LISTEN_PORT = intSshPort;
           };
           service.DISABLE_REGISTRATION = true;
         };
@@ -55,10 +51,8 @@ in
     net.expose.tcp = [ 3000 ];
   };
 
-  ci-runner =
+  ci-runner = mkVm {
-    mkVm {
     name = "ci-runner";
-      includedInTests = false;
     net.access = [
       {
         to = "git";
@@ -68,7 +62,7 @@ in
     ];
     svc.autoStart = true;
     resources.cpu = 4;
-      resources.mem = "32G";
+    resources.mem = "8G";
     resources.fs = [
       {
         proto = "virtiofs";
@@ -76,12 +70,6 @@ in
         source = "${ciRunnerData}/nix-rw-store";
         mountPoint = "/nix/.rw-store";
       }
-        {
-          proto = "virtiofs";
-          tag = "nix-db";
-          source = "${ciRunnerData}/nix-db";
-          mountPoint = "/nix/var/nix/db";
-        }
       {
         proto = "virtiofs";
         tag = "docker-data";
@@ -92,7 +80,7 @@ in
         proto = "virtiofs";
         tag = "runner-state";
         source = "${ciRunnerData}/runner-state";
-          mountPoint = "/var/lib/private/gitea-runner";
+        mountPoint = "/var/lib/gitea-runner";
       }
       {
         proto = "virtiofs";
@@ -101,12 +89,6 @@ in
         mountPoint = "/run/ci-runner-secrets";
         readOnly = true;
       }
-        {
-          proto = "virtiofs";
-          tag = "tmp";
-          source = "/tmp";
-          mountPoint = "/tmp";
-        }
     ];
     guestConfig =
       {
@@ -118,24 +100,20 @@ in
       let
         runnerInstanceName = "ci-runner";
 
-          ciJobContents = with pkgs; [
+        ciJobImage = pkgs.dockerTools.buildLayeredImage {
+          name = "ci-job-image";
+          tag = "latest";
+          contents = with pkgs; [
             bashInteractive
             coreutils
             gitMinimal
             nixVersions.latest
             nodejs
             cacert
-            (writeTextDir "etc/nix/nix.conf" "experimental-features = nix-command flakes\n")
           ];
-
-          ciJobImage = pkgs.dockerTools.buildLayeredImage {
-            name = "ci-job-image";
-            tag = "latest";
-            contents = ciJobContents;
           config = {
             Cmd = [ "/bin/sh" ];
             Env = [
-                "PATH=${lib.makeBinPath ciJobContents}"
               "SSL_CERT_FILE=${pkgs.cacert}/etc/ssl/certs/ca-bundle.crt"
               "NIX_SSL_CERT_FILE=${pkgs.cacert}/etc/ssl/certs/ca-bundle.crt"
               "NIX_REMOTE=daemon"
@@ -147,10 +125,6 @@ in
         boot.kernelModules = [ "kvm-intel" ];
         boot.extraModprobeConfig = "options kvm_intel nested=1";
 
-          # volume-mounted into CI containers; must be in VM's store so
-          # image symlinks (/bin/node etc.) resolve through the mount
-          system.extraDependencies = ciJobContents;
-
         microvm.writableStoreOverlay = "/nix/.rw-store";
 
         nix.settings = {
@@ -159,35 +133,16 @@ in
             "flakes"
           ];
           max-jobs = "auto";
-            substituters = [ "https://microvm.cachix.org" ];
-            trusted-public-keys = [ "microvm.cachix.org-1:oXnBc6hRE3eX5rSYdRyMYXnfzcCxC7yKPTbZXALsqys=" ];
         };
 
-          nix.settings = {
+        nix.gc = {
-            min-free = 5 * 1024 * 1024 * 1024;
+          automatic = true;
-            max-free = 10 * 1024 * 1024 * 1024;
+          dates = "daily";
+          options = "--delete-older-than 14d";
         };
         # nix.optimise.automatic = true; - doesn't work with microvm.writableStoreOverlay
 
-          services.openssh = {
-            enable = true;
-            settings = {
-              PermitRootLogin = "yes";
-              PermitEmptyPasswords = "yes";
-            };
-          };
-          users.users.root.initialHashedPassword = "";
-          services.journald.extraConfig = "ForwardToConsole=yes";
-
-          virtualisation.containerd.enable = true;
-          virtualisation.containerd.settings.plugins."io.containerd.snapshotter.v1.overlayfs".mount_options =
-            [ "userxattr" ];
-
         virtualisation.docker.enable = true;
-          virtualisation.docker.extraOptions = "--containerd /run/containerd/containerd.sock";
-          virtualisation.docker.daemon.settings.exec-opts = [ "native.cgroupdriver=cgroupfs" ];
-          systemd.services.docker.wants = [ "containerd.service" ];
-          systemd.services.docker.after = [ "containerd.service" ];
 
         systemd.services.load-ci-job-image = {
           description = "Load the CI job Docker image";
@@ -219,15 +174,5 @@ in
           };
         };
       };
-    }
-    // {
-      hostConfig = {
-        systemd.tmpfiles.rules = [
-          "d ${ciRunnerData}/nix-rw-store 0755 server server -"
-          "d ${ciRunnerData}/nix-db 0755 server server -"
-          "d ${ciRunnerData}/docker 0755 server server -"
-          "d ${ciRunnerData}/runner-state 0755 server server -"
-        ];
-      };
   };
 }

containers/server-n0/nginx.nix

@@ -210,6 +210,6 @@ let
     };
     inherit (setup) containerConfig;
   };
-  inherit (c) hostAddr;
+  hostAddr = c.hostAddr;
 in
 c

containers/server-n0/ssh.nix

@@ -61,21 +61,16 @@ let
       net ? { },
       resources ? { },
       traits ? [ ],
-      isolation ? { },
     }:
     mkContainer {
       inherit name;
       inherit net resources;
       svc.autoStart = true;
-      isolation = {
+      isolation.nixDaemon = nixDaemon;
-        inherit nixDaemon;
-      }
-      // isolation;
       traits = [ sshTrait ] ++ traits;
       packages = with pkgs; [ tmux ] ++ packages;
       miscProperties = self._sshpiperRegister routingInfo;
     };
-
 in
 {
   ssh-admin = mkSsh {

dsl.nix

@@ -565,11 +565,6 @@ rec {
               Destination = "0.0.0.0/0";
               Gateway = hostAddr;
             };
-            networkConfig.DNS = [ hostAddr ];
-            networkConfig.Domains = [
-              "~."
-              "containers"
-            ];
             linkConfig.RequiredForOnline = if allowInternet then "routable" else "degraded";
           };
           networking.enableIPv6 = false;

flake.nix

@@ -129,10 +129,11 @@
     {
       nixosConfigurations = lib.mapAttrs (_: host: host.hostCfg) allHosts;
 
-      inspect = lib.mapAttrs (
+      inspect = lib.mapAttrs
-        name: host:
+        (name: host:
-        pkgs.writeText "inspect-${name}.json" (builtins.toJSON (introspect.hostReport { inherit host; }))
+          pkgs.writeText "inspect-${name}.json"
-      ) allHosts;
+            (builtins.toJSON (introspect.hostReport { inherit host; })))
+        allHosts;
 
       packages.${system} = customPkgs // {
         inherit ci;

tests/server-n0/integration.py

@@ -211,7 +211,12 @@ with subtest("(isolation): edges are one-way"):
     server.fail(ct_connect("git", ADDR["nginx"], 443, timeout=2))
 
 with subtest("(isolation): host access allowlist"):
-    server.succeed(ct_connect("overseer", HOST_ADDR["overseer"], HOST_EXPORTER_PORT))
+    server.succeed(
+        net_cmd(
+            "overseer",
+            f"{CURL} -sf --max-time 5 http://{HOST_ADDR['overseer']}:{HOST_EXPORTER_PORT}/metrics >&2",
+        )
+    )
     for port in (HOST_EXPORTER_PORT, HOST_CADVISOR_PORT):
         server.fail(ct_connect("git", HOST_ADDR["git"], port, timeout=2))
         server.fail(ct_connect("git", HOST_ADDR["overseer"], port, timeout=2))