Use cachix in CI.

.travis.yml

@@ -2,15 +2,15 @@ language: nix
 nix: 2.1.3
 
 install:
-  # nix-env -iA cachix -f https://cachix.org/api/v1/install
+  - nix-env -iA cachix -f https://cachix.org/api/v1/install
 
 before_install:
   - git lfs pull
 
 script:
-  # cachix authtoken "$CACHIX_AUTH_TOKEN" >/dev/null
-  # cachix use urbit
+  - cachix authtoken "$CACHIX_AUTH_TOKEN" >/dev/null
+  - cachix use urbit2
   - make
   - make test
   - sh/update-brass-pill # To verify that this works.
-  # ./sh/cachix
+  - ./sh/cachix

nix/dep-repos.nix

@@ -7,10 +7,8 @@ with (import ./deps {});
 {
   argon2-src     = argon2.src;
   ed25519-src    = ed25519.src;
-  ent-src        = ent.src;
   h2o-src        = h2o.src;
   murmur3-src    = murmur3.src;
-  nodehello-src  = nodehello.src;
   scrypt-src     = scrypt.src;
   secp256k1-src  = secp256k1.src;
   sni-src        = sni.src;

sh/cachix

@@ -5,6 +5,10 @@ fail () {
   exit 1
 }
 
+if [ -z "$CACHIX_SIGNING_KEY" ]
+then fail "The CACHIX_AUTH_TOKEN environment variable needs to be set."
+fi
+
 if [ -z "$CACHIX_AUTH_TOKEN" ]
 then fail "The CACHIX_AUTH_TOKEN environment variable needs to be set."
 fi
@@ -16,7 +20,7 @@ cleanup () {
 trap cleanup EXIT
 
 cachix authtoken "$CACHIX_AUTH_TOKEN" >/dev/null
-cachix use urbit
+cachix use urbit2
 nix-build nix/dep-repos.nix > .cache.list
 nix-build default.nix >> .cache.list
-cachix push urbit < .cache.list
+cachix push urbit2 < .cache.list