bitdefender. But even after turning off firewall again and turning off bitdefender:
(v1.1) pkg> build CodecZlib
Building CodecZlib → `~/.julia/packages/CodecZlib/9jDi1/deps/build.log`
┌ Error: Error building `CodecZlib`:
│ [ Info: Downloading https://github.com/bicycle1885/ZlibBuilder/releases/download/v1.0.4/Zlib.v1.2.11.x86_64-apple-darwin14.tar.gz to /Users/Nick/.julia/packages/CodecZlib/9jDi1/deps/usr/downloads/Zlib.v1.2.11.x86_64-apple-darwin14.tar.gz...
│ ERROR: LoadError: Could not download https://github.com/bicycle1885/ZlibBuilder/releases/download/v1.0.4/Zlib.v1.2.11.x86_64-apple-darwin14.tar.gz to /Users/Nick/.julia/packages/CodecZlib/9jDi1/deps/usr/downloads/Zlib.v1.2.11.x86_64-apple-darwin14.tar.gz:
│ ErrorException("")
│ Stacktrace:
│ [1] error(::String) at ./error.jl:33
│ [2] #download#89(::Bool, ::Function, ::String, ::String) at /Users/Nick/.julia/packages/BinaryProvider/4F5Hq/src/PlatformEngines.jl:498
│ [3] #download at ./none:0 [inlined]
│ [4] #download_verify#90(::Bool, ::Bool, ::Bool, ::Function, ::String, ::String, ::String) at /Users/Nick/.julia/packages/BinaryProvider/4F5Hq/src/PlatformEngines.jl:567
│ [5] #download_verify at ./none:0 [inlined]
│ [6] #install#129(::Prefix, ::String, ::Bool, ::Bool, ::Bool, ::Function, ::String, ::String) at /Users/Nick/.julia/packages/BinaryProvider/4F5Hq/src/Prefix.jl:314
│ [7] (::getfield(BinaryProvider, Symbol("#kw##install")))(::NamedTuple{(:prefix, :force, :verbose),Tuple{Prefix,Bool,Bool}}, ::typeof(install), ::String, ::String) at ./none:0
│ [8] top-level scope at /Users/Nick/.julia/packages/CodecZlib/9jDi1/deps/build.jl:89
│ [9] include at ./boot.jl:326 [inlined]
│ [10] include_relative(::Module, ::String) at ./loading.jl:1038
│ [11] include(::Module, ::String) at ./sysimg.jl:29
│ [12] include(::String) at ./client.jl:403
│ [13] top-level scope at none:0
│ in expression starting at /Users/Nick/.julia/packages/CodecZlib/9jDi1/deps/build.jl:78
│ [19:13:48] dyld: Library not loaded: @rpath/libssl.1.0.0.dylib
│ [19:13:48] Referenced from: /Users/Nick/anaconda/lib/libssh2.1.dylib
│ [19:13:48] Reason: image not found
└ @ Pkg.Operations /Users/osx/buildbot/slave/package_osx64/build/usr/share/julia/stdlib/v1.1/Pkg/src/Operations.jl:1075