[ci] Offloading CI versioning to argotest.

This commits simplifies the CI setup for this repository, offloading
all complexity to the "argotest" repository.

.gitlab-ci.yml

 stages:
+  - build
   - test
 
 integration.test:
@@ -20,3 +21,68 @@ integration.test:
     - /^WIP\/.*/
   tags:
     - integration
+
+
+.nix-build:
+  stage: build
+  tags:
+    - integration
+
+.nix-integration:
+  stage: test
+  artifacts:
+    paths:
+      - _output/cmd_err.log
+      - _output/cmd_out.log
+      - _output/daemon_out.log
+      - _output/daemon_out.log
+      - _output/nrm.log
+      - _output/.argo_nodeos_config_exit_message
+    expire_in: 1 week
+  except:
+    - /^wip\/.*/
+    - /^WIP\/.*/
+  tags:
+    - integration
+
+containers.build:
+  extends: .nix-build
+  script:
+    - CACHE=$(mktemp -d --suffix=nixcache /tmp/deletable-nix-cache-XXXX)
+    - XDG_CACHE_HOME=$CACHE nix-build .nix -A containers
+    - rm -rf $CACHE
+
+libnrm.build:
+  extends: .nix-build
+  script:
+    - CACHE=$(mktemp -d --suffix=nixcache /tmp/deletable-nix-cache-XXXX)
+    - XDG_CACHE_HOME=$CACHE nix-build .nix -A libnrm
+    - rm -rf $CACHE
+
+nrm.build:
+  extends: .nix-build
+  script:
+    - CACHE=$(mktemp -d --suffix=nixcache /tmp/deletable-nix-cache-XXXX)
+    - XDG_CACHE_HOME=$CACHE nix-build .nix -A nrm
+    - rm -rf $CACHE
+
+TestHello.test:
+  extends: .nix-integration
+  script:
+    - CACHE=$(mktemp -d --suffix=nixcache /tmp/deletable-nix-cache-XXXX)
+    - XDG_CACHE_HOME=$CACHE nix-shell .nix -A test --run "argotk.hs TestHello"
+    - rm -rf $CACHE
+
+TestListen.test:
+  extends: .nix-integration
+  script:
+    - CACHE=$(mktemp -d --suffix=nixcache /tmp/deletable-nix-cache-XXXX)
+    - XDG_CACHE_HOME=$CACHE nix-shell .nix -A test --run "argotk.hs TestListen"
+    - rm -rf $CACHE
+
+TestPerfwrapper.test:
+  extends: .nix-integration
+  script:
+    - CACHE=$(mktemp -d --suffix=nixcache /tmp/deletable-nix-cache-XXXX)
+    - XDG_CACHE_HOME=$CACHE nix-shell .nix -A test --run "argotk.hs TestPerfwrapper"
+    - rm -rf $CACHE

.nix/default.nix

+let argotest =
+  builtins.fetchTarball
+  "https://xgitlab.cels.anl.gov/argo/argotest/-/archive/master/argotest-master.tar.gz";
+in import "${argotest}/test.nix" {
+  containers-override = ./..;
+  testName = "base";
+}