Difficulties installing package from npm

When installing these neon npm modules, either your `disk-utility` or my `ssb-neon-keys`, both give an error upon `npm install` that looks like this:

```
➜ npm i

> disk-utility@0.0.2 install /home/staltz/oss/someproject/node_modules/disk-utility
> node-pre-gyp install --fallback-to-build=false || neon build --release

sh: 1: node-pre-gyp: not found
neon ERR! Command failed: cargo metadata --format-version=1 --no-deps
error: could not find `Cargo.toml` in `/home/staltz/oss/someproject/node_modules/disk-utility/native` or any parent directory
```

or

```
➜ npm i

> ssb-neon-keys@7.2.0-2 postinstall /home/staltz/oss/someproject/node_modules/ssb-neon-keys
> node-pre-gyp install --fallback-to-build=false || neon build --release

sh: 1: node-pre-gyp: not found
neon ERR! spawn cargo ENOENT

Error: spawn cargo ENOENT
```

This seems to be the case regardless if `node-pre-gyp` is defined in `package.json > scripts > install` or `package.json > scripts > postinstall`. I'm wondering if you stumbled upon this error before, and how did you resolve it?

More info on my local setup:

```
➜ npm version
{ someproject: '1.0.0',
npm: '6.4.1',
ares: '1.15.0',
cldr: '33.1',
http_parser: '2.8.0',
icu: '62.1',
modules: '64',
napi: '3',
nghttp2: '1.34.0',
node: '10.15.3',
openssl: '1.1.0j',
tz: '2018e',
unicode: '11.0',
uv: '1.23.2',
v8: '6.8.275.32-node.51',
zlib: '1.2.11' }
```

```
➜ uname -a
Linux computername 4.15.0-117-generic #118-Ubuntu SMP Fri Sep 4 20:02:41 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
```

```
➜ cargo -V
cargo 1.40.0 (bc8e4c8be 2019-11-22)
```