Key the TRUSTED_PROXIES rule to the source address seen on arrival

The README and the TrustedProxies comment now say, once per passage,
that the list must be set to the proxy's address alone if any client
can reach webhooker or the proxy from an RFC 1918 source address,
directly or through anything that can rewrite source addresses, and
that the address to set is the remoteIP field of the http request log
line. The loopback case in the reverse-proxy checklist is now a proxy
reaching the binary bound to 127.0.0.1. Other sentences about which
clients can choose their own rate-limit key are cut.

Model: opus-5-5

.dockerignore

@@ -3,10 +3,8 @@
 # stage of the Dockerfile.
 .git/
 bin/
-# Third-party browser assets are fetched and hash-verified inside the build by
+# Extracted from 3p/ by `make assets` inside the build; a host copy is not
-# script/fetch-assets. Excluding any host copy keeps a developer's working tree
+# needed. The tarball in 3p/ must stay in the context.
-# from supplying the bytes that get shipped. The script and its
-# static/vendor.sha256 manifest stay in the context.
 static/js/alpine.min.js
 *.md
 LICENSE

.gitignore

@@ -46,7 +46,6 @@ temp/
 # CI cache barrier, written into the build context by the check workflow
 .ci-fingerprint
 
-# Third-party browser assets, fetched and hash-verified by
+# Alpine.js, extracted by `make assets` from its tarball in 3p/, which is
-# script/fetch-assets against static/vendor.sha256. Not committed:
+# what is committed.
-# REPO_POLICIES.md forbids minified bundles in version control.
 /static/js/alpine.min.js

Dockerfile

@@ -51,15 +51,8 @@ RUN go mod download
 # the lint stage above.
 COPY . .
 
-# Fetch the third-party browser assets the UI serves. They are not committed
+# Run tests and build. Both first run script/assets, which extracts Alpine.js
-# (REPO_POLICIES.md forbids minified bundles in version control) and
+# from its tarball in 3p/.
-# .dockerignore keeps any host copy out of the build context, so this step is
-# the only way they enter the image. Each download is checked against a
-# hardcoded sha256 and the build fails on mismatch; make test re-checks the
-# hashes against the bytes go:embed actually put in the binary.
-RUN script/fetch-assets
-
-# Run tests and build
 RUN make test
 
 # Version stamped into the binary. .dockerignore excludes .git/, so
@@ -67,8 +60,8 @@ RUN make test
 # host and passes it in. The default is what a bare `docker build .`
 # with no --build-arg gets, and it names no tag the tree may not be at.
 #
-# Declared here, below the test and asset steps, so a changed version
+# Declared here, below the test step, so a changed version does not
-# does not invalidate their cached layers.
+# invalidate its cached layer.
 ARG VERSION=unknown
 
 RUN make build VERSION="$VERSION"

Makefile

@@ -28,7 +28,7 @@ setup:
 	@script/setup
 
 assets:
-	@script/fetch-assets
+	@script/assets
 
 test:
 	@script/test
@@ -45,13 +45,13 @@ fmt-check:
 check:
 	@script/check
 
-build:
+build: assets
 	go build -ldflags '$(strip -X main.version=$(VERSION) $(GO_LDFLAGS))' -o bin/webhooker ./cmd/webhooker
 
 run: build
 	./bin/webhooker
 
-dev:
+dev: assets
 	go run ./cmd/webhooker
 
 deps:

README.md

@@ -21,9 +21,6 @@ before deploying one.
 - Go 1.26.1+ (the version in `go.mod`)
 - Docker (for linting, for the test stage of the CI gate, and for
   containerized deployment)
-- `curl`, used by `script/fetch-assets` to download the third-party
-  browser assets, which are not committed (`make bootstrap` installs
-  it if missing)
 
 golangci-lint is not a prerequisite and must not be installed on the
 host: `script/bootstrap` does not install it, and `make lint` runs the
@@ -36,9 +33,7 @@ digest-pinned linter image via `Dockerfile.lint`.
 git clone https://git.eeqj.de/sneak/webhooker.git
 cd webhooker
 
-# Install Go dependencies and the third-party browser assets.
+# Install the Go toolchain if missing, and the Go dependencies
-# `make deps` alone is not enough: it only runs go mod download/tidy,
-# and the checks below need the fetched assets.
 make bootstrap
 
 # Run all checks (test, lint, format check)
@@ -58,7 +53,7 @@ make docker
 ```bash
 make bootstrap  # Install all dependencies (idempotent)
 make setup      # Bootstrap + install git pre-commit hook
-make assets     # Fetch + verify third-party browser assets
+make assets     # Extract Alpine.js from 3p/ (test, check, build, dev run it)
 make fmt        # Format code (gofmt + goimports)
 make fmt-check  # Fail if gofmt would change anything (writes nothing)
 make lint       # Run golangci-lint in Docker (Dockerfile.lint)
@@ -147,7 +142,7 @@ TTY detection, and security headers are always applied.
 | `RETENTION_SWEEP_INTERVAL` | How often the retention reaper and archive sweeper run (Go duration, must be positive) | `1h` |
 | `SESSION_IDLE_TIMEOUT`  | Idle session timeout (Go duration)  | `24h`    |
 | `RECEIVER_RATE_LIMIT`   | Receiver requests/minute per IP per entrypoint (10x that per IP across the route) | `120` |
-| `TRUSTED_PROXIES`       | CIDRs whose forwarded headers are trusted. A set value replaces the default. Under the default, any client with a private address, whether it connects directly or through a trusted proxy, can choose its own rate-limit key by sending its own `X-Forwarded-For`; if any clients have private addresses, set it to the proxy's address alone. See [Trusted proxies](#trusted-proxies) | `10.0.0.0/8,172.16.0.0/12,192.168.0.0/16` (RFC 1918) |
+| `TRUSTED_PROXIES`       | CIDRs whose forwarded headers are trusted. A set value replaces the default. If any client can reach webhooker, or the proxy in front of it, from an RFC 1918 source address, set it to the proxy's address alone. See [Trusted proxies](#trusted-proxies) | `10.0.0.0/8,172.16.0.0/12,192.168.0.0/16` (RFC 1918) |
 | `ALLOWED_EGRESS_CIDRS`  | CIDRs that delivery targets may reach despite the SSRF blocklist. Read [Allowing egress to your own network](#allowing-egress-to-your-own-network) before setting it | `""` (none) |
 
 #### Allowing egress to your own network
@@ -386,35 +381,24 @@ the addresses of your reverse proxies.
 inside one of these blocks; for every other peer the client identity is
 the connection's own address and the header is ignored. Unset (or
 empty), the list is the RFC 1918 private ranges: `10.0.0.0/8`,
-`172.16.0.0/12` and `192.168.0.0/16`. That covers a reverse proxy
+`172.16.0.0/12` and `192.168.0.0/16`. A set value replaces the default
-reaching webhooker over a Docker network or a private LAN without
+entirely. A set but unparseable value aborts startup.
-anything set. A set value replaces the default entirely. A set but
-unparseable value aborts startup.
 
-Trusting those ranges has two consequences for clients with private
+If any client can reach webhooker, or the proxy in front of it, from an
-addresses:
+RFC 1918 source address (directly, or through anything that can
+rewrite source addresses, such as NAT or a published container port),
+set `TRUSTED_PROXIES` to the proxy's address alone, or every rate
+limit, the webhook receiver's included, can be bypassed by those
+clients. The address to set is the `remoteIP` field of the
+`http request` log line for a request that came through the proxy.
 
-- Any such client, whether it connects directly or through the proxy,
+Behind a proxy the list does not cover, every request keys on the
-  can choose its own rate-limit key by sending its own
+proxy's own address and all clients share a single bucket per limit.
-  `X-Forwarded-For`. A direct client's header is walked because the
+The receiver limits become service-wide ceilings, and the login
-  client is itself trusted; behind the proxy, the client's own address
+endpoint's failure counting collapses onto one key, so a stranger's
-  is skipped as a trusted hop when the chain is walked (below), so the
+wrong passwords throttle every other client's wrong passwords. Set
-  entry it wrote is taken as the client. If any of your clients have
+`TRUSTED_PROXIES` to that proxy's address to restore per-client
-  private addresses, you must set `TRUSTED_PROXIES` to the proxy's
+buckets.
-  address alone.
-- A client behind the proxy that sends no `X-Forwarded-For` of its own
-  shares the proxy's bucket, because its own address is skipped too.
-  Setting the list to the proxy's address alone gives each its own
-  bucket.
-
-A proxy the list does not cover, such as nginx on the same host
-reaching webhooker over loopback, is not trusted: every request through
-it keys on the proxy's own address and all clients share a single
-bucket per limit. The receiver limits become service-wide ceilings,
-and the login endpoint's failure counting collapses onto one key, so a
-stranger's wrong passwords throttle every other client's wrong
-passwords. Set `TRUSTED_PROXIES` to that proxy's address to restore
-per-client buckets.
 
 What it cannot do is lock the operator out. The login endpoint
 verifies credentials **before** it consults any limit and charges only
@@ -436,20 +420,10 @@ instead, since past such an entry the chain is not the shape assumed
 here. The peer address is likewise used when the header is absent or
 every hop in it is a trusted proxy.
 
-Two operator requirements follow:
+Your proxy must therefore **append** the peer address to
-
+`X-Forwarded-For` (nginx `$proxy_add_x_forwarded_for`, HAProxy
-- Your proxy must **append** the peer address to `X-Forwarded-For`
+`option forwardfor`, Caddy and AWS ALB by default), and must append a
-  (nginx `$proxy_add_x_forwarded_for`, HAProxy `option forwardfor`,
+bare address with no port.
-  Caddy and AWS ALB by default), and must append a bare address with
-  no port.
-- Keep clients out of the list. Any address inside `TRUSTED_PROXIES`
-  chooses its own rate-limit key: its `X-Forwarded-For` is walked, so
-  it can name a different address on every request to get a fresh
-  bucket each time, or name another client's address to drain that
-  client's bucket. A block that also covers clients — the default, on
-  a network where clients have private addresses — makes every rate
-  limit, including the unauthenticated webhook receiver's, silently
-  bypassable by every client in the block.
 
 #### Sessions
 
@@ -748,15 +722,14 @@ repository's `Dockerfile` and runs it. The app needs:
 - **Volume:** one host directory mounted at `/var/lib/webhooker`.
 - **Environment variables:**
     - `WEBHOOKER_ENVIRONMENT=prod`
-    - `TRUSTED_PROXIES`: Docker networks use private addresses, so the
+    - `TRUSTED_PROXIES`: unset, it is the RFC 1918 ranges. Set it to
-      default covers your reverse proxy on that network. Under the
+      your reverse proxy's address alone if that address is outside
-      default, any client with a private address, whether it connects
+      those ranges, or if any client can reach webhooker, or the proxy,
-      directly or through the proxy, can choose its own rate-limit key
+      from an RFC 1918 source address (directly, or through anything
-      by sending its own `X-Forwarded-For`. If any clients have private
+      that can rewrite source addresses, such as NAT or a published
-      addresses, or the network's addresses are outside the RFC 1918
+      container port). The `remoteIP` field of the `http request` log
-      ranges, set it to the proxy's address there. The `remoteIP` field
+      line for a request that came through the proxy shows that
-      of the `http request` log line for a request that came through
+      address; the health check's own lines show `::1`. See
-      the proxy shows it; the health check's own lines show `::1`. See
       [Trusted proxies](#trusted-proxies).
     - Leave `BIND_ADDRESS` and `DATA_DIR` unset: the image sets
       `BIND_ADDRESS` to `0.0.0.0`, and `DATA_DIR` defaults to
@@ -820,14 +793,16 @@ reports.
    behind a proxy means the `X-Forwarded-Proto` header. The block below
    sets it; without it every request is read as plaintext and cookies
    ship without `Secure`. See [Configuration](#configuration).
-3. **Make sure `TRUSTED_PROXIES` covers the proxy's address.** Unset,
+3. **Make sure `TRUSTED_PROXIES` covers the proxy's address.** For a
-   it covers the RFC 1918 private ranges, so a proxy on a Docker
+   proxy it does not cover, every rate limiter keys on the proxy, so
-   network or a private LAN is covered and one on loopback is not. For
+   all clients share one bucket per limit. Unset, the list is the RFC
-   a proxy it does not cover, every rate limiter keys on the connecting
+   1918 ranges, which do not cover a proxy that reaches the binary
-   peer, which is the proxy on every request: all clients collapse into
+   itself over loopback (the binary bound to `127.0.0.1`). With the
-   one global bucket per limit and the receiver's per-IP limits become
+   image, the address to check is the `remoteIP` field of the
-   service-wide ceilings. See [Trusted proxies](#trusted-proxies). If
+   `http request` log line for a request that came through the proxy.
-   any clients have private addresses, list the proxy and nothing else.
+   If any client can reach webhooker, or the proxy, from an RFC 1918
+   source address, set the list to the proxy's address alone. See
+   [Trusted proxies](#trusted-proxies).
 4. **Send `Host` as `$http_host`, not `$host`.** `$host` strips the
    port. webhooker's Origin/Referer check compares against the host it
    was given, so on any port other than 443 `$host` makes every form
@@ -1236,14 +1211,15 @@ This repository adheres to the
 standard: normalized scripts in `script/` are the entrypoints for the
 development workflow. Ten of the Makefile's seventeen targets are thin
 shims that call them; `build`, `run`, `dev`, `deps`, `clean`, `css` and
-`version` are inline commands with no script behind them, though
+`version` are inline commands with no script behind them, though `build`,
-`build` and `version` both take their value from `script/version`.
+`run` and `dev` first run `script/assets`, and `build` and `version` both
+take their value from `script/version`.
 
-`make check` needs the third-party browser assets in `static/`, which
+`script/test`, `make build` and `make dev` each run `script/assets`
-are not committed, so run `make bootstrap` (or just `make assets`) once
+first, which writes the ignored `static/js/alpine.min.js` (see
-after cloning. Without them the tests fail with a message naming that
+[Third-party browser assets](#third-party-browser-assets)), so
-remedy. `make check` does not fetch them itself because it must not
+`make test`, `make check` and the pre-commit hook work on a fresh clone
-change any files in the repo.
+without a separate step.
 
 We provide:
 
@@ -1251,8 +1227,8 @@ We provide:
 - `script/setup` — make a fresh clone ready for development
   (bootstrap, then install-precommit)
 - `script/projectname` — output the project name ("webhooker")
-- `script/fetch-assets` — download the third-party browser assets into
+- `script/assets` — extract Alpine.js from its tarball in `3p/` (see
-  `static/`, verifying each against its pinned sha256
+  [Third-party browser assets](#third-party-browser-assets))
 - `script/test` — run the test suite
 - `script/lint` — run golangci-lint in Docker (see Linting below)
 - `script/fmt` — format all code (writes)
@@ -1274,24 +1250,25 @@ We provide:
 
 ## Third-party browser assets
 
-The web UI serves one third-party script, Alpine.js. It is **not** committed:
+The web UI serves one third-party script, Alpine.js. Its npm package tarball
-a minified bundle in the tree is unreviewable, and `REPO_POLICIES.md` bars
+is committed as `3p/alpinejs-3.14.9.tgz`, byte for byte as the npm registry
-both committed build artifacts and unpinned external references.
+publishes it. It is a dependency, not this repo's build output, so
+`REPO_POLICIES.md`'s rule against committed build artifacts does not apply.
+The directory is `3p/` rather than `vendor/` because Go treats a root
+`vendor/` directory as its module vendor directory.
 
-Instead `script/fetch-assets` downloads it from a pinned URL, checks the
+`script/assets` (`make assets`) extracts the browser build,
-download against a hardcoded sha256, and installs it under `static/`. The
+`package/dist/cdn.min.js`, from the tarball to `static/js/alpine.min.js`,
-sha256 of every installed asset is recorded in `static/vendor.sha256`, and
+where `go:embed` picks it up. `script/test`, `make build` and `make dev` run
-`static/vendor_test.go` re-hashes the bytes `go:embed` put in the binary
+it first, and the Dockerfile builds through `make test` and `make build`, so
-against that manifest — so the pin is enforced on what actually ships, not
+nothing downloads Alpine.js. The extracted file is not committed, and
-merely written down. Any mismatch fails the build.
+`.dockerignore` keeps any host copy out of the build context.
 
-`make bootstrap` runs the fetch for local development, and the Dockerfile
+To move to a new version: download
-runs it in the build stage; `.gitignore` and `.dockerignore` keep the
+`https://registry.npmjs.org/alpinejs/-/alpinejs-<version>.tgz`, check it
-artifact out of both the repo and the build context.
+against the `dist.integrity` hash listed at
-
+`https://registry.npmjs.org/alpinejs/<version>`, replace the tarball in `3p/`
-To move to a new version: update the version, URL, and tarball sha256 in
+with it, update its file name in `script/assets`, and run `make check`.
-`script/fetch-assets` and the asset sha256 in `static/vendor.sha256`, then
-run `make assets && make check`.
 
 ## Rationale
 
@@ -2573,20 +2550,16 @@ opposite directions:
 - For the **receiver** limits it costs throughput, which is the safe
   direction to be wrong in: sharing can only make a limit bind sooner,
   never let a sender past it. It matters more for the aggregate limit
-  than for the per-entrypoint one: when `TRUSTED_PROXIES` does not
+  than for the per-entrypoint one: with every request keyed on the
-  cover the reverse proxy a production deployment is required to run
+  proxy, the aggregate limit becomes a service-wide ceiling of 1200
-  behind, every request keys on the proxy, so the aggregate limit
+  requests per minute across all senders and all entrypoints, where the
-  becomes a service-wide ceiling of 1200 requests per minute across all
+  per-entrypoint limit's capacity still grows with the number of
-  senders and all entrypoints, where the per-entrypoint limit's
+  entrypoints.
-  capacity still grows with the number of entrypoints. Any deployment
-  with more than a handful of busy entrypoints must make sure
-  `TRUSTED_PROXIES` covers its proxy.
 - For the **login and password-change** limits it costs precision, not
   availability. Login failures from every client land in one counter,
   so a stranger's wrong passwords make the operator's own wrong
   passwords answer `429` sooner; the operator's _correct_ password is
-  never affected, because it is never counted. Production deployments
+  never affected, because it is never counted.
-  should still make sure `TRUSTED_PROXIES` covers their proxy.
 
 #### The login endpoint
 
@@ -2774,6 +2747,8 @@ imports. The entry point is `cmd/webhooker/main.go`.
 
 ```
 webhooker/
+├── 3p/
+│   └── alpinejs-3.14.9.tgz    # Alpine.js npm package, extracted by make assets
 ├── cmd/webhooker/
 │   └── main.go               # Entry point: subcommand dispatch; no args locks DATA_DIR and wires fx
 ├── internal/
@@ -2867,8 +2842,7 @@ webhooker/
 │   ├── css/tailwind.css       # Generated stylesheet the pages load
 │   ├── css/style.css          # Older hand-written stylesheet, no longer loaded
 │   ├── js/app.js              # Progressive-enhancement copy-to-clipboard
-│   ├── js/alpine.min.js       # Alpine.js, fetched by script/fetch-assets, not committed
+│   └── js/alpine.min.js       # Alpine.js, extracted from 3p/ by make assets, not committed
-│   └── vendor.sha256          # Pinned hashes the fetched assets are verified against
 ├── templates/                 # Go HTML templates (base, login, sources, etc.)
 ├── script/                    # Scripts to Rule Them All entrypoints
 ├── Dockerfile                 # Three stages: lint, test+build, Alpine runtime
@@ -3179,14 +3153,14 @@ version is fixed independently of the compiler's:
    `make fmt-check`, then `golangci-lint config verify` and
    `golangci-lint run`, both with `--network=none`.
 2. **Builder stage** (`golang:1.26.1-bookworm`) — depends on the lint
-   stage passing (it copies a file from it), runs `script/fetch-assets`
+   stage passing (it copies a file from it), runs `make test` and
-   to download and verify the third-party browser assets, then runs
+   `make build` (both extract Alpine.js from `3p/` first), and finally
-   `make test` and `make build`, and finally rebuilds the binary with
+   rebuilds the binary with `CGO_ENABLED=1` and static linking so it
-   `CGO_ENABLED=1` and static linking so it runs on musl. Both builds
+   runs on musl. Both builds go through `make build`, the relink adding
-   go through `make build`, the relink adding its `-extldflags` via
+   its `-extldflags` via `GO_LDFLAGS`, so neither can drop the `-X` that
-   `GO_LDFLAGS`, so neither can drop the `-X` that stamps the version.
+   stamps the version. The version arrives as the `VERSION` build arg,
-   The version arrives as the `VERSION` build arg, since the context
+   since the context has no `.git` (see
-   has no `.git` (see [Version stamping](#version-stamping)).
+   [Version stamping](#version-stamping)).
 3. **Runtime stage** (`alpine:3.21`) — copies the static binary and
    `deploy/docker-entrypoint.sh`, creates the `/var/lib/webhooker`
    directory for all SQLite databases, exposes port 8080, and includes

internal/config/config.go

@@ -178,13 +178,13 @@ type Config struct {
 	// TrustedProxies is the set of networks whose members are
 	// allowed to speak for the client with X-Forwarded-For, the
 	// only forwarded header read. Unless TRUSTED_PROXIES is set it
-	// is the RFC 1918 private ranges (defaultTrustedProxies).
+	// is the RFC 1918 private ranges (defaultTrustedProxies); a set
-	// Other peers' forwarded headers are ignored and they are
+	// value replaces them. If any client can reach the process, or
-	// identified by the connection's own address. Under the
+	// the proxy in front of it, from an RFC 1918 source address
-	// default any client with a private address, directly or
+	// (directly, or through anything that can rewrite source
-	// through a trusted proxy, can choose its own rate-limit
+	// addresses, such as NAT or a published container port), it
-	// key, so where any clients have private addresses this must
+	// must be set to the proxy's address alone, or every rate limit
-	// be set to the proxy hosts alone.
+	// can be bypassed by those clients.
 	TrustedProxies []netip.Prefix
 
 	// AllowedEgressCIDRs is the set of networks a delivery target

internal/server/static_assets_test.go

@@ -13,9 +13,9 @@ import (
 
 // TestBaseTemplateScriptsAreServed walks every /s/ script the base
 // template loads on each page and fetches it through the real router.
-// Alpine.js is fetched at build time rather than committed, so nothing
+// Alpine.js is extracted from its tarball in 3p/ at build time, so the
-// in the repo guarantees it is present: this is the check that the page
+// file is not in the tree: this is the check that the page still gets
-// still gets the JavaScript it asks for.
+// the JavaScript it asks for.
 func TestBaseTemplateScriptsAreServed(t *testing.T) {
 	t.Parallel()
 

script/assets

@@ -0,0 +1,16 @@
+#!/bin/sh
+# script/assets: extract Alpine.js from its npm package tarball, committed
+# in 3p/, to static/js/alpine.min.js, where go:embed reads it. The
+# extracted file is not committed. script/test, make build and make dev run
+# this first.
+set -eu
+
+ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
+
+main() {
+    cd "$ROOT"
+    tar -xzOf 3p/alpinejs-3.14.9.tgz package/dist/cdn.min.js \
+        >static/js/alpine.min.js
+}
+
+main "$@"

script/bootstrap

@@ -4,9 +4,7 @@
 # installed tools are skipped. Base tooling comes from nix, apt, brew,
 # or apk (detected in that order); assumes NOTHING is present (not git,
 # make, or go). golangci-lint is deliberately not installed: linting runs
-# only in docker, via script/lint and Dockerfile.lint. Finishes by running
+# only in docker, via script/lint and Dockerfile.lint.
-# script/fetch-assets, which installs the hash-pinned third-party browser
-# assets the repo does not commit.
 set -eu
 
 ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
@@ -69,11 +67,6 @@ main() {
 
     go mod download
 
-    # Third-party browser assets are not committed; fetch and verify them
-    # so a fresh clone can build and test.
-    if missing curl; then pkg_install curl curl curl curl; fi
-    "$ROOT/script/fetch-assets"
-
     echo "bootstrap complete"
 }
 

script/check

@@ -1,6 +1,7 @@
 #!/bin/sh
 # script/check: run all checks (test, lint, fmt-check). Our own
-# extension to scripts-to-rule-them-all. Must not modify any files.
+# extension to scripts-to-rule-them-all.
+# Writes only the ignored static/js/alpine.min.js, through script/test.
 # Generic: usually needs no adaptation.
 set -eu
 

script/fetch-assets

@@ -1,104 +0,0 @@
-#!/bin/sh
-# script/fetch-assets: download the third-party browser assets the web UI
-# ships and install them under static/. Minified bundles are not committed
-# (REPO_POLICIES.md: no build artifacts in version control), so the build
-# fetches them here. Every download is verified against a hardcoded sha256
-# before it is installed, and any mismatch aborts. Idempotent: an asset
-# already present with its pinned hash is left alone.
-set -eu
-
-ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
-
-# The sha256 of each installed asset lives in static/vendor.sha256, in
-# sha256sum(1) format, with paths relative to static/. That file is the
-# single source of truth: this script verifies against it, and
-# static/vendor_test.go asserts the bytes embedded into the binary match
-# it, so the hash cannot rot into a value nothing checks.
-MANIFEST="static/vendor.sha256"
-
-# Alpine.js 3.14.9, 2026-08-17. Fetched from registry.npmjs.org, the
-# publisher of record; the jsDelivr and unpkg copies are mirrors of this
-# same tarball. dist/cdn.min.js is the browser build Alpine publishes for
-# a <script> tag.
-ALPINE_VERSION="3.14.9"
-ALPINE_URL="https://registry.npmjs.org/alpinejs/-/alpinejs-${ALPINE_VERSION}.tgz"
-# sha256 of alpinejs-3.14.9.tgz
-ALPINE_TARBALL_SHA256="97dad7c0c81e659cfc8e7700055da9770f8186187cb9a8a76efb57e00d5ce52a"
-ALPINE_MEMBER="package/dist/cdn.min.js"
-ALPINE_DEST="js/alpine.min.js"
-
-sha256_of() {
-    if command -v sha256sum >/dev/null 2>&1; then
-        sha256sum "$1" | cut -d' ' -f1
-    else
-        shasum -a 256 "$1" | cut -d' ' -f1
-    fi
-}
-
-# expected_sha256 <path-relative-to-static>
-expected_sha256() {
-    awk -v want="$1" '$2 == want { print $1; found = 1 }
-        END { if (!found) exit 1 }' "$ROOT/$MANIFEST"
-}
-
-# verify <file> <expected-sha256> <what>
-verify() {
-    actual="$(sha256_of "$1")"
-    if [ "$actual" != "$2" ]; then
-        echo "fetch-assets: sha256 mismatch for $3" >&2
-        echo "  expected: $2" >&2
-        echo "  actual:   $actual" >&2
-        exit 1
-    fi
-}
-
-# up_to_date <path-relative-to-static> <expected-sha256>
-up_to_date() {
-    [ -f "$ROOT/static/$1" ] || return 1
-    [ "$(sha256_of "$ROOT/static/$1")" = "$2" ]
-}
-
-fetch_alpine() {
-    want="$(expected_sha256 "$ALPINE_DEST")"
-
-    if up_to_date "$ALPINE_DEST" "$want"; then
-        echo "fetch-assets: static/$ALPINE_DEST already at $want"
-        return 0
-    fi
-
-    echo "fetch-assets: fetching Alpine.js $ALPINE_VERSION from $ALPINE_URL"
-    tmp="$(mktemp -d)"
-    trap 'rm -rf "$tmp"' EXIT INT TERM
-    curl -fsSL -o "$tmp/alpine.tgz" "$ALPINE_URL"
-    verify "$tmp/alpine.tgz" "$ALPINE_TARBALL_SHA256" "alpinejs-${ALPINE_VERSION}.tgz"
-    tar -xzOf "$tmp/alpine.tgz" "$ALPINE_MEMBER" >"$tmp/alpine.min.js"
-    verify "$tmp/alpine.min.js" "$want" "$ALPINE_MEMBER from alpinejs-${ALPINE_VERSION}.tgz"
-
-    mkdir -p "$(dirname "$ROOT/static/$ALPINE_DEST")"
-    cp "$tmp/alpine.min.js" "$ROOT/static/$ALPINE_DEST"
-    rm -rf "$tmp"
-    trap - EXIT INT TERM
-    echo "fetch-assets: installed static/$ALPINE_DEST ($want)"
-}
-
-# Re-check every manifest entry against what is now on disk, so an entry
-# no script installs fails loudly instead of passing silently.
-verify_manifest() {
-    while read -r want path; do
-        case "$want" in '' | '#'*) continue ;; esac
-        if [ ! -f "$ROOT/static/$path" ]; then
-            echo "fetch-assets: $MANIFEST lists static/$path, which is missing" >&2
-            exit 1
-        fi
-        verify "$ROOT/static/$path" "$want" "static/$path"
-    done <"$ROOT/$MANIFEST"
-}
-
-main() {
-    cd "$ROOT"
-    fetch_alpine
-    verify_manifest
-    echo "fetch-assets: all assets in $MANIFEST verified"
-}
-
-main "$@"

script/test

@@ -28,6 +28,7 @@ ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
 
 main() {
     cd "$ROOT"
+    "$ROOT/script/assets"
     go test -v -race -timeout 90s ./...
 }
 

static/vendor.sha256

@@ -1 +0,0 @@
-3ed1eed252488921df65e363d6715deb04d7f92aaedb9e52199fdf73cb1e0ad3  js/alpine.min.js

static/vendor_test.go

@@ -1,92 +0,0 @@
-package static_test
-
-import (
-	"bufio"
-	"crypto/sha256"
-	"encoding/hex"
-	"os"
-	"strings"
-	"testing"
-
-	"github.com/stretchr/testify/require"
-
-	"sneak.berlin/go/webhooker/static"
-)
-
-const manifestPath = "vendor.sha256"
-
-// fetchHint is appended to every failure here: the assets the manifest
-// covers are fetched by the build, not committed, so a fresh clone that
-// has not run script/fetch-assets fails this test and should be told why.
-const fetchHint = "run `script/fetch-assets` (or `make assets`) to install " +
-	"the pinned third-party assets"
-
-// TestVendoredAssetsMatchManifest asserts that every asset listed in
-// static/vendor.sha256 is embedded in the binary with exactly the pinned
-// bytes. script/fetch-assets verifies the same hashes at download time;
-// this test verifies them again on what actually ships, so a build that
-// skipped, cached, or subverted the fetch cannot produce a binary serving
-// unpinned third-party JavaScript.
-func TestVendoredAssetsMatchManifest(t *testing.T) {
-	t.Parallel()
-
-	entries := readManifest(t)
-	require.NotEmpty(t, entries, "%s lists no assets", manifestPath)
-
-	for path, want := range entries {
-		t.Run(path, func(t *testing.T) {
-			t.Parallel()
-
-			data, err := static.Static.ReadFile(path)
-			require.NoErrorf(
-				t, err,
-				"%s is listed in %s but is not embedded; %s",
-				path, manifestPath, fetchHint,
-			)
-
-			sum := sha256.Sum256(data)
-			got := hex.EncodeToString(sum[:])
-			require.Equalf(
-				t, want, got,
-				"embedded %s does not match its pinned sha256 in %s; %s",
-				path, manifestPath, fetchHint,
-			)
-		})
-	}
-}
-
-// readManifest parses static/vendor.sha256, which is in sha256sum(1)
-// format with paths relative to static/.
-func readManifest(t *testing.T) map[string]string {
-	t.Helper()
-
-	f, err := os.Open(manifestPath)
-	require.NoError(t, err, "opening %s", manifestPath)
-
-	defer func() { require.NoError(t, f.Close()) }()
-
-	entries := make(map[string]string)
-	scanner := bufio.NewScanner(f)
-
-	for scanner.Scan() {
-		line := strings.TrimSpace(scanner.Text())
-		if line == "" || strings.HasPrefix(line, "#") {
-			continue
-		}
-
-		fields := strings.Fields(line)
-		require.Lenf(
-			t, fields, 2,
-			"%s: malformed entry %q, want \"<sha256>  <path>\"",
-			manifestPath, line,
-		)
-
-		sum, path := fields[0], fields[1]
-		require.Lenf(t, sum, 64, "%s: %q is not a sha256", manifestPath, sum)
-		entries[path] = sum
-	}
-
-	require.NoError(t, scanner.Err(), "reading %s", manifestPath)
-
-	return entries
-}