In part 1 of this sit down with Carl Dong, Murch and Jonas get into the weeds of all things build system. Stay tuned for the second half of this conversation when Carl describes his recent adventures isolating the libconsensus engine. In this conversation, we cover: - GUIX (2:25)  - talk at 2019 Breaking Bitcoin about reproducible builds - Gitian builds (4:15) - Fake time (4:50) - Timestamps and reproducibility of packages (6:33) - reproducible-builds.org (6:57)  - SOURCE_DATE_EPOCH - Toolchains (14:40) - Windows Builds and reproducibility (15:20)  - GCC libtool pointer confusion - NSIS (20:25) - Using Debian as an example (22:56) - User choice in their security model (28:15) - Making the process accessible (31:20) - Mac OS X Toolchain & SDK and cross-compiling (33:30) Thanks as always to Matthew Zipkin for the sound engineering.