@@ -72,53 +72,22 @@
7272 # Host package set, for the wrapper app below.
7373 pkgsHost = nixpkgs.legacyPackages.${system};
7474
75− # Name/tag baked into the image's OCI config.
75+ # Default image name (for `copyWith`); `c init` passes a per-directory
76+ # name (`nix-container-<dir>`) to `copyWithShell` instead.
7677 imageName = "nix-container";
7778 imageTag = "latest";
7879
79− # Fish prompt config. Installed at /etc/fish/prompt.fish and loaded via
80− # `fish --no-config --init-command` (see `cmd` below), NOT from
81− # $HOME/.config/fish — so the `~/.config` mount can't shadow it. Built
82− # on the host arch (just a text file), so no Linux builder is needed.
83− fishConfig = pkgsHost.writeText "prompt.fish" ''
84− # No welcome banner.
85− set -g fish_greeting
86−
87− # Define the prompt as a function so fish renders it before every
88− # command; at top level it would run once at startup and be ignored.
89− function fish_prompt
90− set -l nix_shell_info
91− if set -q IN_NIX_SHELL; or set -q IN_NIX_RUN
92− set nix_shell_info ' ❄️'
93− end
94−
95− set -l cwd (prompt_pwd)
96−
97− set -l bookmark_info
98− if jj root 2>/dev/null >/dev/null
99− set -l jj_bookmark (jj log -r 'heads(::@ & bookmarks())' -T 'local_bookmarks ++ "\n"' --no-graph 2>/dev/null | tail -1)
100− if test -n "$jj_bookmark"
101− set bookmark_info ' ' (set_color brmagenta) $jj_bookmark (set_color normal)
102− end
103− end
104−
105− echo -n -s (set_color $fish_color_cwd) $cwd (set_color normal) $bookmark_info ' 🏗️' $nix_shell_info '> '
106− end
107− '';
108−
109− # Lay the prompt out at the path the cmd sources.
110− fishRoot = pkgsHost.runCommand "fish-prompt" { } ''
111− mkdir -p "$out/etc/fish"
112− cp ${fishConfig} "$out/etc/fish/prompt.fish"
113− '';
114−
115− # Build the OCI image from a `{ pkgs, nur }: [ ... ]` package function.
116− # The image always runs /bin/fish; fish, its prompt config, and Nix are
117− # bundled automatically, so `container.nix` lists only your extras.
80+ # Build the OCI image (named `name`) from a `{ pkgs, nur }: [ ... ]`
81+ # package function, for the named shell. The image's `cmd` is herdr
82+ # (the session `c start` attaches to); the shell is the default `$SHELL`
83+ # (what herdr panes spawn) and is added automatically, so `container.nix`
84+ # lists only your extras. Nix (+ CA certs) and the ncurses terminfo
85+ # database are always shipped too. Nothing here is fish-specific: the
86+ # TERM fixup happens host-side in `c` (passed via `-e TERM` at create).
11887 mkImage =
119− packages:
88+ name: shell: packages:
12089 n2c.buildImage {
121− name = imageName;
90+ inherit name;
12291 tag = imageTag;
12392 inherit arch;
12493
@@ -126,10 +95,6 @@
12695 # buildEnv only *symlinks* paths (never runs them), so build it on
12796 # the host arch — the tree is arch-neutral and links the
12897 # (substituted) Linux store paths, sparing the Linux builder.
129− #
130− # Always shipped: fish (the cmd) + its prompt, and Nix (+ CA certs)
131− # so every container can use Nix; `initializeNixDatabase` registers
132− # the baked store.
13398 copyToRoot = pkgsHost.buildEnv {
13499 name = "root";
135100 paths =
@@ -137,16 +102,30 @@
137102 pkgs = pkgsLinux;
138103 nur = nurPkgs;
139104 }
105+ # The shell (cmd + $SHELL), when it exists in nixpkgs.
106+ ++ pkgsLinux.lib.optional (pkgsLinux ? ${shell}) pkgsLinux.${shell}
140107 ++ [
141− pkgsLinux.fish
142− fishRoot
143108 pkgsLinux.nix
144109 pkgsLinux.cacert
110+ # Basic userland (ls, cat, cp, sleep, …) so the container is
111+ # usable out of the box and tools that shell out don't fail.
112+ pkgsLinux.coreutils-full
113+ # Networking glue glibc needs: /etc/nsswitch.conf (+passwd,
114+ # group) so DNS/host lookups resolve, and /etc/protocols,
115+ # /etc/services. Without these, hostname resolution fails.
116+ pkgsLinux.fakeNss
117+ pkgsLinux.iana-etc
118+ # The terminfo database (+ tput/clear/reset) so TUIs find the
119+ # entry for whatever TERM `c` passes in and render correctly.
120+ pkgsLinux.ncurses
121+ # The session `c start` always launches.
122+ pkgsLinux.herdr
145123 ];
124+ # Link all of /etc so the above files (nsswitch.conf, protocols,
125+ # services, passwd, group, ssl certs) are present.
146126 pathsToLink = [
147127 "/bin"
148− "/etc/fish"
149− "/etc/ssl"
128+ "/etc"
150129 ];
151130 };
152131
@@ -154,23 +133,30 @@
154133
155134 config = {
156135 # `cmd` (not `entrypoint`): the default command, *replaced* by any
157− # command passed to `container run/create`. `--no-config` skips
158− # $HOME/.config/fish (so a mounted ~/.config can't override the
159− # prompt); `--init-command` loads the bundled prompt instead.
160− cmd = [
161− "/bin/fish"
162− "--no-config"
163− "--init-command"
164− "source /etc/fish/prompt.fish"
165− ];
136+ # command passed to `container run/create`. Plain herdr here;
137+ # `c init` overrides it with `herdr session attach <dir>-container` so
138+ # the session is named per project. `c start` attaches via
139+ # `container start -ai`; exiting herdr (PID1) stops the container.
140+ cmd = [ "/bin/herdr" ];
166141 env = [
167142 "PATH=/bin"
168143 "HOME=/root"
144+ # Default shell for tools that spawn one (herdr panes, etc.).
145+ "SHELL=/bin/${shell}"
169146 # Marker so shells/scripts can detect they're in here.
170147 "NIX_CONTAINER=1"
171− # Make the bundled Nix usable: TLS for substituters/flakes,
172− # flake commands on, and single-user (no daemon/nixbld).
148+ # Advertise truecolor for 24-bit-aware tools; `c` passes the
149+ # resolved TERM via -e (the runtime would otherwise force xterm).
150+ "COLORTERM=truecolor"
151+ # A UTF-8 locale so tools handle multibyte/wide characters
152+ # correctly. glibc ships C.UTF-8 built in, so this needs no
153+ # locale-archive.
154+ "LANG=C.UTF-8"
155+ # CA trust for every TLS client (curl/git/…) and Nix.
156+ "SSL_CERT_FILE=/etc/ssl/certs/ca-bundle.crt"
173157 "NIX_SSL_CERT_FILE=/etc/ssl/certs/ca-bundle.crt"
158+ # Make the bundled Nix usable: flake commands on, and
159+ # single-user (no daemon/nixbld).
174160 "NIX_CONFIG=experimental-features = nix-command flakes\nbuild-users-group =\nsandbox = false"
175161 ];
176162 };
@@ -178,7 +164,7 @@
178164
179165 # `nix run . -- init|start` runs the bundled `c` manager script. Its
180166 # `init` builds the image from the project's `container.nix` (via
181− # `lib.copyWith`); the script finds the flake from its own (store)
167+ # `lib.copyWithShell`); the script finds the flake from its own (store)
182168 # location, so this works from a checkout or straight from
183169 # `nix run github:…/nix-container`.
184170 cApp = pkgsHost.writeShellScriptBin "c" ''
@@ -191,15 +177,22 @@
191177 default = flake-utils.lib.mkApp { drv = cApp; };
192178 };
193179
194− # Build helpers. `c init` uses `copyWith` to honour a per-project
195− # `container.nix`:
180+ # Build helpers take a `{ pkgs, nur }: [ ... ]` packages function (the
181+ # `packages` attr of a project's `container.nix`). `c init` uses
182+ # `copyWithShell` (host shell baked in); `copyWith` is the generic form:
196183 # (builtins.getFlake "github:…/nix-container")
197− # .lib.<system>.copyWith (import ./container.nix)
184+ # .lib.<system>.copyWith (import ./container.nix).packages
198185 lib = {
199186 inherit mkImage;
200− # skopeo copy app (`skopeo copy nix:<image> "$@"`) for an image built
201− # from a `{ pkgs, nur }: [ ... ]` function.
202− copyWith = packages: (mkImage packages).copyTo;
187+ # Build the image's `copyTo` script (a skopeo-copy wrapper) from a
188+ # `{ pkgs, nur }: [ ... ]` function, named `imageName`. Defaults the
189+ # shell (cmd + $SHELL) to bash; use `copyWithShell` to pick another.
190+ copyWith = packages: (mkImage imageName "bash" packages).copyTo;
191+ # Like `copyWith`, but for the given image `name` and shell — `c init`
192+ # passes `nix-container-<dir>` and the host login shell, which is added
193+ # to the image and used as cmd + $SHELL without being listed in
194+ # `container.nix`.
195+ copyWithShell = name: shell: packages: (mkImage name shell packages).copyTo;
203196 };
204197 }
205198 );