diff --git a/.circleci/config.yml b/.circleci/config.yml
index d3699778f..8789fa1fa 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -192,16 +192,16 @@ workflows:
           requires:
             - setup
       - test:
-          name: test-golang-1.13
+          name: test-golang-1.15
           resource_class: xlarge
-          golang_version: 1.13.15
+          golang_version: 1.15.3
           requires:
             - setup
           filters:
             tags:
               only: /^v.*/
       - test:
-          name: test-golang-1.14
+          name: test-golang-1.14.9
           resource_class: xlarge
           golang_version: 1.14.9
           requires:
@@ -216,7 +216,7 @@ workflows:
       #  name: test-golang-<< matrix.golang_version >>
       #  matrix:
       #    parameters:
-      #      golang_version: ["1.14.9", "1.13.15"]
+      #      golang_version: ["1.14.9", "1.15.3"]
       - test:
           name: test-race
           test_make_target: test-race
@@ -248,7 +248,7 @@ workflows:
           requires:
             - linter
             - check-license-headers
-            - test-golang-1.14
+            - test-golang-1.14.9
       - dockerhub-upload-unstable:
           context: molecula
           requires:
diff --git a/Dockerfile b/Dockerfile
index a0950ffed..33df2d063 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM golang:1.13.0 as builder
+FROM golang:1.15.3 as builder
 
 ARG BUILD_FLAGS
 ARG MAKE_FLAGS
diff --git a/Makefile b/Makefile
index b1b7d567c..6d9afe8d0 100644
--- a/Makefile
+++ b/Makefile
@@ -38,11 +38,11 @@ vendor: go.mod
 
 # Run test suite
 test:
-	go test ./... -tags='$(BUILD_TAGS) $(TEST_TAGS)' $(TESTFLAGS) -v
+	GODEBUG=x509ignoreCN=0 go test ./... -tags='$(BUILD_TAGS) $(TEST_TAGS)' $(TESTFLAGS) -v
 
 # Run test suite with race flag
 test-race:
-	go test ./... -tags='$(BUILD_TAGS) $(TEST_TAGS)' $(TESTFLAGS) -race -timeout 60m -v
+	GODEBUG=x509ignoreCN=0 go test ./... -tags='$(BUILD_TAGS) $(TEST_TAGS)' $(TESTFLAGS) -race -timeout 60m -v
 
 testv: topt testvsub
 
@@ -57,7 +57,7 @@ testvsub:
 	set -e; for i in boltdb ctl http pg pql rbf roaring server sql txkey; do \
            echo; echo "___ testing subpkg $$i"; \
            cd $$i; pwd; \
-           go test -tags='$(BUILD_TAGS) $(TEST_TAGS)' $(TESTFLAGS) -v -timeout 60m || break; \
+           GODEBUG=x509ignoreCN=0 go test -tags='$(BUILD_TAGS) $(TEST_TAGS)' $(TESTFLAGS) -v -timeout 60m || break; \
            echo; echo "999 done testing subpkg $$i"; \
            cd ..; \
         done
@@ -66,7 +66,7 @@ testvsub-race:
 	set -e; for i in boltdb ctl http pg pql rbf roaring server sql txkey; do \
            echo; echo "___ testing subpkg $$i -race"; \
            cd $$i; pwd; \
-           go test -tags='$(BUILD_TAGS) $(TEST_TAGS)' $(TESTFLAGS) -v -race -timeout 60m || break; \
+           GODEBUG=x509ignoreCN=0 go test -tags='$(BUILD_TAGS) $(TEST_TAGS)' $(TESTFLAGS) -v -race -timeout 60m || break; \
            echo; echo "999 done testing subpkg $$i -race"; \
            cd ..; \
         done
@@ -75,7 +75,7 @@ tour:
 	./tournament.sh
 
 bench:
-	go test ./... -bench=. -run=NoneZ -timeout=127m $(TESTFLAGS)
+	GODEBUG=x509ignoreCN=0 go test ./... -bench=. -run=NoneZ -timeout=127m $(TESTFLAGS)
 
 # Run test suite with coverage enabled
 cover:
@@ -205,20 +205,20 @@ pilosa-fsck:
 
 # Run Pilosa tests inside Docker container
 docker-test:
-	docker run --rm -v $(PWD):/go/src/$(CLONE_URL) -w /go/src/$(CLONE_URL) golang:$(GO_VERSION) go test -tags='$(BUILD_TAGS) $(TEST_TAGS)' $(TESTFLAGS) ./...
+	docker run --rm -v $(PWD):/go/src/$(CLONE_URL) -w /go/src/$(CLONE_URL) golang:$(GO_VERSION) GODEBUG=x509ignoreCN=0 go test -tags='$(BUILD_TAGS) $(TEST_TAGS)' $(TESTFLAGS) ./...
 
 # Must use bash in order to -o pipefail; otherwise the tee will hide red tests.
 # run top tests, not subdirs. print summary red/green after.
 # The \-\-\- FAIL avoids counting the extra two FAIL strings at then bottom of log.topt.
 topt:
 	mv log.topt.roar log.topt.roar.prev || true
-	$(eval SHELL:=/bin/bash) set -o pipefail; go test -v -tags='$(BUILD_TAGS) $(TEST_TAGS)' $(TESTFLAGS) 2>&1 | tee log.topt.roar
+	$(eval SHELL:=/bin/bash) set -o pipefail; GODEBUG=x509ignoreCN=0 go test -v -tags='$(BUILD_TAGS) $(TEST_TAGS)' $(TESTFLAGS) 2>&1 | tee log.topt.roar
 	@echo "   log.topt.roar green: \c"; cat log.topt.roar | grep PASS |wc -l
 	@echo "   log.topt.roar   red: \c"; cat log.topt.roar | grep '\-\-\- FAIL' | wc -l
 
 topt-race:
 	mv log.topt.race log.topt.race.prev || true
-	$(eval SHELL:=/bin/bash) set -o pipefail; go test -race -v -tags='$(BUILD_TAGS) $(TEST_TAGS)' $(TESTFLAGS) 2>&1 | tee log.topt.race
+	$(eval SHELL:=/bin/bash) set -o pipefail; GODEBUG=x509ignoreCN=0 go test -race -v -tags='$(BUILD_TAGS) $(TEST_TAGS)' $(TESTFLAGS) 2>&1 | tee log.topt.race
 	@echo "   log.topt.race green: \c"; cat log.topt.race | grep PASS |wc -l
 	@echo "   log.topt.race   red: \c"; cat log.topt.race | grep '\-\-\- FAIL' | wc -l
 
diff --git a/server/testdata/certs/README.md b/server/testdata/certs/README.md
index 6e1a23d30..98f685f56 100644
--- a/server/testdata/certs/README.md
+++ b/server/testdata/certs/README.md
@@ -10,3 +10,5 @@ certstrap --depot-path certs sign "localhost" --CA pilosa-ca --expires "100 year
 dev-25ea708a
 
 (built with go 1.13)
+
+`GODEBUG=x509ignoreCN=0` is needed to run server tests since go 1.15 to avoid certificate errors.
diff --git a/txfactory.go b/txfactory.go
index 09f80e44a..da0b9497b 100644
--- a/txfactory.go
+++ b/txfactory.go
@@ -44,7 +44,7 @@ const (
 // DefaultTxsrc is set here. pilosa/server/config.go references it
 // to set the default for pilosa server exeutable.
 // Can be overridden with env variable PILOSA_TXSRC for testing.
-const DefaultTxsrc = RoaringTxn
+const DefaultTxsrc = RBFTxn
 
 // DetectMemAccessPastTx true helps us catch places in api and executor
 // where mmapped memory is being accessed after the point in time