gistfile1.txt

  nixpkgs.config.packageOverrides = super: {
    hydra = super.hydra.overrideDerivation (old : {
      version = "2017-09-14";
      src = pkgs.fetchFromGitHub {
        owner = "NixOS";
        repo = "hydra";
        rev = "b828224fee451ad26e87cfe4eeb9c0704ee1062b";
        sha256 = "05xv10ldsa1rahxbbgh5kwvl1dv4yvc8idczpifgb55fgqj8zazm";
      };
    });
    # nixUnstable = super.nixUnstable.overrideDerivation(old : {
    #  name = "nix-2.0pre5951_690ac7c9";
    #  src = pkgs.fetchFromGitHub {
    #    owner = "NixOS";
    #    repo = "nix";
    #    rev = "690ac7c90b5bf3c599e210c53365c7d229c8b0ff";
    #    sha256 = "1yn2p38kp1i67makbawr1rhdiwihgnvk2zwrz0gvf6q65mj2k89c";
    #  };
    # });
  };

gistfile2.txt

building
build flags: -j1 -l1 SHELL=/nix/store/jgw8hxx7wzkyhb2dr9hwsd9h2caaasdc-bash-4.4-p12/bin/bash
make  all-recursive
make[1]: Entering directory '/tmp/nix-build-hydra-2017-09-14.drv-0/hydra-b828224fee451ad26e87cfe4eeb9c0704ee1062b-src'
Making all in src
make[2]: Entering directory '/tmp/nix-build-hydra-2017-09-14.drv-0/hydra-b828224fee451ad26e87cfe4eeb9c0704ee1062b-src/src'
Making all in hydra-evaluator
make[3]: Entering directory '/tmp/nix-build-hydra-2017-09-14.drv-0/hydra-b828224fee451ad26e87cfe4eeb9c0704ee1062b-src/src/hydra-evaluator'
g++ -DHAVE_CONFIG_H -I. -I../..    -I/nix/store/bz87vr1vd7rzmhvpn3lvwgix7wmn5pbq-boehm-gc-7.6.0-dev/include -I/nix/store/j4pp7ih5qcqg8qkhay99x83v83x6qfyn-nix-unstable-1.12pre5873_b76e282d-dev/include/nix -Wall -I ../libhydra -g -O2 -std=c++17 -include nix/config.h -c -o hydra_evaluator-hydra-evaluator.o `test -f 'hydra-evaluator.cc' || echo './'`hydra-evaluator.cc
/nix/store/jgw8hxx7wzkyhb2dr9hwsd9h2caaasdc-bash-4.4-p12/bin/bash ../../libtool  --tag=CXX   --mode=link g++ -I/nix/store/bz87vr1vd7rzmhvpn3lvwgix7wmn5pbq-boehm-gc-7.6.0-dev/include -I/nix/store/j4pp7ih5qcqg8qkhay99x83v83x6qfyn-nix-unstable-1.12pre5873_b76e282d-dev/include/nix -Wall -I ../libhydra -g -O2 -std=c++17 -include nix/config.h   -o hydra-evaluator hydra_evaluator-hydra-evaluator.o -L/nix/store/agiyfa6fj25p52qshx9p4zwb4ks5kw0a-boehm-gc-7.6.0/lib -L/nix/store/y5rc1z1ldj2c5l0qf22khf1kflcq5j0i-nix-unstable-1.12pre5873_b76e282d/lib -lnixmain -lnixexpr -lgc -lnixstore -lnixutil -lnixformat -lpqxx 
libtool: link: g++ -I/nix/store/bz87vr1vd7rzmhvpn3lvwgix7wmn5pbq-boehm-gc-7.6.0-dev/include -I/nix/store/j4pp7ih5qcqg8qkhay99x83v83x6qfyn-nix-unstable-1.12pre5873_b76e282d-dev/include/nix -Wall -I ../libhydra -g -O2 -std=c++17 -include nix/config.h -o hydra-evaluator hydra_evaluator-hydra-evaluator.o  -L/nix/store/agiyfa6fj25p52qshx9p4zwb4ks5kw0a-boehm-gc-7.6.0/lib -L/nix/store/y5rc1z1ldj2c5l0qf22khf1kflcq5j0i-nix-unstable-1.12pre5873_b76e282d/lib -lnixmain -lnixexpr /nix/store/agiyfa6fj25p52qshx9p4zwb4ks5kw0a-boehm-gc-7.6.0/lib/libgc.so -L/nix/store/03wjkacvndsxhp540pgmsxhas8j610lc-libatomic_ops-7.6.0/lib -lpthread -ldl -lnixstore -lnixutil -lnixformat -lpqxx -Wl,-rpath -Wl,/nix/store/agiyfa6fj25p52qshx9p4zwb4ks5kw0a-boehm-gc-7.6.0/lib -Wl,-rpath -Wl,/nix/store/agiyfa6fj25p52qshx9p4zwb4ks5kw0a-boehm-gc-7.6.0/lib
make[3]: Leaving directory '/tmp/nix-build-hydra-2017-09-14.drv-0/hydra-b828224fee451ad26e87cfe4eeb9c0704ee1062b-src/src/hydra-evaluator'
Making all in hydra-eval-jobs
make[3]: Entering directory '/tmp/nix-build-hydra-2017-09-14.drv-0/hydra-b828224fee451ad26e87cfe4eeb9c0704ee1062b-src/src/hydra-eval-jobs'
g++ -DHAVE_CONFIG_H -I. -I../..    -I/nix/store/bz87vr1vd7rzmhvpn3lvwgix7wmn5pbq-boehm-gc-7.6.0-dev/include -I/nix/store/j4pp7ih5qcqg8qkhay99x83v83x6qfyn-nix-unstable-1.12pre5873_b76e282d-dev/include/nix -g -O2 -std=c++17 -include nix/config.h -c -o hydra-eval-jobs.o hydra-eval-jobs.cc
hydra-eval-jobs.cc:13:26: fatal error: common-opts.hh: No such file or directory
 #include "common-opts.hh"
                          ^
compilation terminated.
make[3]: *** [Makefile:410: hydra-eval-jobs.o] Error 1
make[3]: Leaving directory '/tmp/nix-build-hydra-2017-09-14.drv-0/hydra-b828224fee451ad26e87cfe4eeb9c0704ee1062b-src/src/hydra-eval-jobs'
make[2]: *** [Makefile:363: all-recursive] Error 1
make[2]: Leaving directory '/tmp/nix-build-hydra-2017-09-14.drv-0/hydra-b828224fee451ad26e87cfe4eeb9c0704ee1062b-src/src'
make[1]: *** [Makefile:417: all-recursive] Error 1
make[1]: Leaving directory '/tmp/nix-build-hydra-2017-09-14.drv-0/hydra-b828224fee451ad26e87cfe4eeb9c0704ee1062b-src'
make: *** [Makefile:347: all] Error 2
build time elapsed:  0m0.116s 0m0.078s 0m6.034s 0m0.815s
builder for ‘/nix/store/g66cd2gn8j82jaybzdj0kpd12dl4kmla-hydra-2017-09-14.drv’ failed with exit code 2