make build-bin: on Linux, build with bun's pinned release build (closes #240)

nix's bun loads through a glibc in the nix store, and bun build --compile
copied that loader into bin/quak, so nix-collect-garbage could break the
cron backup. The build moves into script/build-bin. On Linux it downloads
bun 1.3.13's release archive for the machine from GitHub: x86-64
(baseline) or arm64, glibc or musl. It checks the archive's SHA-256
before running it, and compiles with that bun, so the binary loads
through the system loader. macOS still runs bun through nix-shell.

Model: opus-5-5

Makefile

@@ -26,10 +26,8 @@ check:
 build:
 	@script/build
 
-# Bundles the built dist/, so the binary reports the version script/build
-# stamped.
-build-bin: build
-	nix-shell -p bun --run "bun build dist/bin/quak.js --compile --outfile bin/quak"
+build-bin:
+	@script/build-bin
 
 install: build-bin
 	mkdir -p ~/bin

README.md

@@ -135,10 +135,16 @@ requests. The "Library reference" below covers both.
 ## Running the backup from cron
 
 `quak backup` never prompts, so cron can run it. `make install` builds quak as
-one binary and copies it to `~/bin/quak`. Besides what Getting Started needs,
-`make install` needs `make` and [nix](https://nixos.org/download). It uses bun,
-a JavaScript runtime, to bundle the built `dist/` into one executable. It runs
-bun through `nix-shell -p bun`.
+one binary and copies it to `~/bin/quak`. It uses bun, a JavaScript runtime, to
+bundle the built `dist/` into one executable. Besides what Getting Started
+needs, `make install` needs `make`. On Linux it downloads bun from GitHub with
+`curl` and unpacks it with `unzip`. It checks the download against a SHA-256
+hash in the repo. On macOS it runs bun through `nix-shell -p bun`, so it needs
+[nix](https://nixos.org/download).
+
+On Linux systems that use the musl C library, such as Alpine, `make install`
+downloads bun's musl build. On Alpine, both that bun and `~/bin/quak` need the
+`libstdc++` and `libgcc` packages.
 
 Log in once with `~/bin/quak`, as the user the cron job will run as:
 
@@ -671,6 +677,9 @@ but letters and digits, or when it is longer than 16 characters.
 When the date or the time zone changes, the next run stores the original at its
 new path and leaves the old copy where it is.
 
+A file deleted in Ente keeps its original at its save path, and the JSON beside
+it. The next run removes its symlinks from the collection directories.
+
 The library gives the same path as `photo.savePath` and writes it with
 `photo.download()` (see "A photo's content").
 
@@ -1771,6 +1780,8 @@ standard. The others are additions to it.
   `package.json` declares (`main`, `types`, `bin`) were written, and make the
   command line executable.
 - `script/version`: print the version `script/build` stamps (see "Version").
+- `script/build-bin`: run `script/build`, then bundle the built `dist/` into one
+  binary, `bin/quak`, with bun (see "Running the backup from cron").
 - `script/test`: run the test suite, by building the `test` phase of the
   `Dockerfile`. Requires Docker.
 - `script/lint`: run eslint and a prettier check, by building the `lint` phase
@@ -1799,8 +1810,7 @@ The Makefile targets are:
 - `make build`: runs `script/build`.
 - `make docker`: runs `script/docker`.
 - `make hooks`: runs `script/install-precommit`.
-- `make build-bin`: bundles the built `dist/` into one binary, `bin/quak`. It
-  runs bun through `nix-shell -p bun`.
+- `make build-bin`: runs `script/build-bin`.
 - `make install`: runs `make build-bin` and copies the binary to `~/bin/quak`.
 - `make dev`: runs the TypeScript compiler in watch mode.
 - `make clean`: removes `dist/`, `coverage/`, `.vitest-cache/` and the
@@ -1908,9 +1918,11 @@ These apply to people and to coding agents alike.
     - container images by digest;
     - the nvm archive `script/bootstrap` downloads, and the Python packages
       `bin/clip-keyword-vectors` installs, by SHA-256 hash;
+    - bun's glibc and musl builds, which `script/build-bin` downloads on Linux,
+      by SHA-256 hash;
     - Node and yarn, when `script/bootstrap` installs them, by version.
 - Not pinned:
-    - bun, which `make build-bin` takes from `nix-shell -p bun`;
+    - bun on macOS, which `script/build-bin` takes from `nix-shell -p bun`;
     - `make` and `git`, which `script/bootstrap` installs from the system
       package manager when they are missing, as every `Dockerfile` stage does;
     - `bash` and `curl`, which `script/bootstrap` installs the same way when it

script/build-bin

@@ -0,0 +1,73 @@
+#!/bin/sh
+# script/build-bin: run script/build, then bundle the built dist/ into one
+# executable, bin/quak, which reports the version script/build stamped. Our own
+# extension to scripts-to-rule-them-all.
+#
+# bun compiles the binary from a copy of its own executable. On Linux, nix's
+# bun loads through a C library in the nix store, and so does a binary compiled
+# from it. nix-collect-garbage can delete that library, and the binary then no
+# longer starts. On Linux this script therefore compiles with bun's own release
+# build, which loads through the system's C library. It downloads that build
+# and checks it against the hash below before running it.
+set -eu
+
+ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
+
+# bun 1.3.13, 2026-11-11, and the SHA-256 of each release archive below. The
+# x86-64 archives are the baseline builds, which also run on CPUs without AVX2.
+# The musl archives are for Linux systems that use the musl C library, such as
+# Alpine.
+BUN_VERSION="1.3.13"
+BUN_LINUX_X64_BASELINE_SHA256="9d8a24292a7068090205daac0a5a223f5f69736f5287e37bf88d3b4031edc750"
+BUN_LINUX_X64_MUSL_BASELINE_SHA256="88ca7c7ad235b498f549eea2f770f434e9f0f5e9ba95168a2d3a1f235184c394"
+BUN_LINUX_AARCH64_SHA256="70bae41b3908b0a120e1e58c5c8af30e74afae3b8d11b0d3fdd8e787ddfb4b22"
+BUN_LINUX_AARCH64_MUSL_SHA256="5385e978107ce4934298d8d6afe9bfbb898683f6cc23e6753a0da60bc60c5b81"
+
+# compile_with_downloaded_bun <archive-name> <sha256>
+compile_with_downloaded_bun() {
+    tmp="$(mktemp -d)"
+    trap 'rm -rf "$tmp"' EXIT
+    curl -fsSL -o "$tmp/$1.zip" \
+        "https://github.com/oven-sh/bun/releases/download/bun-v$BUN_VERSION/$1.zip"
+    echo "$2  $tmp/$1.zip" | sha256sum -c -
+    unzip -q "$tmp/$1.zip" -d "$tmp"
+    "$tmp/$1/bun" build dist/bin/quak.js --compile --outfile bin/quak
+}
+
+main() {
+    cd "$ROOT"
+    "$ROOT/script/build"
+    platform="$(uname -s)-$(uname -m)"
+    # musl's ldd begins its version output with "musl libc"; glibc's does not.
+    if ldd --version 2>&1 | grep -q '^musl libc'; then
+        platform="$platform-musl"
+    fi
+    case "$platform" in
+        Linux-x86_64)
+            compile_with_downloaded_bun bun-linux-x64-baseline \
+                "$BUN_LINUX_X64_BASELINE_SHA256"
+            ;;
+        Linux-x86_64-musl)
+            compile_with_downloaded_bun bun-linux-x64-musl-baseline \
+                "$BUN_LINUX_X64_MUSL_BASELINE_SHA256"
+            ;;
+        Linux-aarch64)
+            compile_with_downloaded_bun bun-linux-aarch64 \
+                "$BUN_LINUX_AARCH64_SHA256"
+            ;;
+        Linux-aarch64-musl)
+            compile_with_downloaded_bun bun-linux-aarch64-musl \
+                "$BUN_LINUX_AARCH64_MUSL_SHA256"
+            ;;
+        Linux-*)
+            echo "build-bin: bun has no release build for Linux on $(uname -m)" >&2
+            exit 1
+            ;;
+        *)
+            nix-shell -p bun --run \
+                "bun build dist/bin/quak.js --compile --outfile bin/quak"
+            ;;
+    esac
+}
+
+main "$@"