./scripts/build/cardano-sl.sh fails can't load .so/.DLL for: libz.so

[woodynew]

[nix-shell:/opt/cardano-sl]$ ./scripts/build/cardano-sl.sh
Going to build: cardano-sl-networking cardano-sl-binary cardano-sl-util cardano-sl-crypto cardano-sl-core cardano-sl-db cardano-sl-chain cardano-sl-infra cardano-sl cardano-sl-node cardano-sl-client cardano-sl-generator cardano-sl-auxx cardano-sl-tools cardano-sl-explorer cardano-sl-wallet
Building cardano-sl-networking

stack build --ghc-options=" -Wwarn" --test --no-haddock-deps --bench --jobs=1 --no-run-tests --no-run-benchmarks --dependencies-only cardano-sl-networking

cardano-sl-binary-3.0.2: build (lib)
Progress 0/14: cardano-sl-binary-3.0.2

-- While building custom Setup.hs for package cardano-sl-binary-3.0.2 using:
/home/ubuntu/.stack/setup-exe-cache/x86_64-linux/Cabal-simple_mPHDZzAJ_2.2.0.1_ghc-8.4.4 --builddir=.stack-work/dist/x86_64-linux/Cabal-2.2.0.1 build lib:cardano-sl-binary --ghc-options " -ddump-hi -ddump-to-file -fdiagnostics-color=always"
Process exited with code: ExitFailure 1
Logs have been written to: /opt/cardano-sl/.stack-work/logs/cardano-sl-binary-3.0.2.log

Preprocessing library for cardano-sl-binary-3.0.2..
Building library for cardano-sl-binary-3.0.2..
[3 of 6] Compiling Pos.Binary.Class.TH ( src/Pos/Binary/Class/TH.hs, .stack-work/dist/x86_64-linux/Cabal-2.2.0.1/build/Pos/Binary/Class/TH.o )
<command line>: can't load .so/.DLL for: libz.so (libz.so: cannot open shared object file: No such file or directory)

[disassembler]

You probably are missing the libz library on your system. We hightly recommend using nix to build cardano-sl as it avoids issues like this one.