So the certs end up in these files:

• /etc/ssl/certs/ca-certificates.crt
• /etc/ssl/certs/ca-bundle.crt
• / etc/pki/tls/certs/ca-bundle.crt

Only the first one is mentioned on stackoverflow as being used by Go on debian.

Curl seems to have its default location compiled in by passing --with-ca-bundle ~~, but after installing curlFull and running curl-config --ca, it doesn't look like that was used and the "default" path is guessed.~~

Looking further in the curl derivation there are these lines for darwin :

lib.optionals stdenv.isDarwin [
      # Disable default CA bundle, use NIX_SSL_CERT_FILE or fallback to nss-cacert from the default profile.
      # Without this curl might detect /etc/ssl/cert.pem at build time on macOS, causing curl to ignore NIX_SSL_CERT_FILE.
      "--without-ca-bundle"
      "--without-ca-path"
    ]

So, check the value of NIX_SSL_CERT_FILE outside nix shell and within. The path might have to be set there. I dunno how to do that automatically with nix shell, so it might have to be done manually.

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