cabal rebuilds the world inside nix develop

[locallycompact]

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The nix build works fine, but

nix develop
cabal build all

results in cabal rebuilding libraries that should already be supplied by the shell

In order, the following will be built (use -v for more details):
 - cardano-data-1.1.0.0 (lib:testlib) (requires download & build)
 - hspec-discover-2.11.4 (lib) (requires download & build)
 - hydra-prelude-0.12.0 (lib) (cannot read state cache)
 - ouroboros-consensus-0.9.0.0 (lib) (requires download & build)
 - plutus-ledger-api-1.7.0.1 (lib) (requires download & build)
 - hspec-discover-2.11.4 (exe:hspec-discover) (requires download & build)
 - ouroboros-consensus-diffusion-0.7.0.0 (lib) (requires download & build)
 - plutus-ledger-api-1.7.0.1 (lib:plutus-ledger-api-testlib) (requires download & build)
 - cardano-ledger-binary-1.1.1.1 (lib) (requires download & build)
 - cardano-ledger-binary-1.1.1.1 (lib:testlib) (requires download & build)
 - cardano-data-1.1.0.0 (lib) (requires download & build)
 - cardano-crypto-wrapper-1.5.1.0 (lib) (requires download & build)
 - small-steps-test-1.0.0.1 (lib) (requires download & build)
 - set-algebra-1.1.0.1 (lib) (requires download & build)
 - cardano-ledger-byron-1.0.0.2 (lib) (requires download & build)
 - cardano-crypto-test-1.5.0.0 (lib) (requires download & build)
 - byron-spec-ledger-1.0.0.1 (lib) (requires download & build)
 - cardano-ledger-core-1.4.1.0 (lib) (requires download & build)
 - byron-spec-chain-1.0.0.1 (lib) (requires download & build)
 - cardano-ledger-shelley-1.4.2.0 (lib) (requires download & build)
 - cardano-ledger-byron-test-1.5.0.0 (lib) (requires download & build)
 - cardano-ledger-allegra-1.2.1.0 (lib) (requires download & build)
 - cardano-ledger-core-1.4.1.0 (lib:testlib) (requires download & build)
 - cardano-ledger-mary-1.3.1.0 (lib) (requires download & build)
 - cardano-ledger-shelley-1.4.2.0 (lib:testlib) (requires download & build)
 - cardano-ledger-alonzo-1.3.3.0 (lib) (requires download & build)
 - cardano-ledger-allegra-1.2.1.0 (lib:testlib) (requires download & build)
 - cardano-ledger-babbage-1.4.2.0 (lib) (requires download & build)
 - cardano-ledger-mary-1.3.1.0 (lib:testlib) (requires download & build)
 - cardano-ledger-conway-1.6.3.0 (lib) (requires download & build)
 - cardano-ledger-alonzo-1.3.3.0 (lib:testlib) (requires download & build)
 - cardano-protocol-tpraos-1.0.3.3 (lib) (requires download & build)
 - cardano-ledger-api-1.3.1.0 (lib) (requires download & build)
 - cardano-ledger-babbage-1.4.2.0 (lib:testlib) (requires download & build)
 - ouroboros-consensus-protocol-0.5.0.4 (lib) (requires download & build)
 - ouroboros-consensus-cardano-0.7.0.0 (lib) (requires download & build)
 - cardano-api-8.11.0.0 (lib:internal) (requires download & build)