diff --git a/.buildkite/pipeline.yml b/.buildkite/pipeline.yml
index 7d85e13cbe6..06fefb95837 100644
--- a/.buildkite/pipeline.yml
+++ b/.buildkite/pipeline.yml
@@ -172,6 +172,14 @@ steps:
     plugins:
       <<: *docker_plugin
 
+  - label: Test fuzz builds
+    branches: master kostko/fix/build-fuzz
+    command:
+      - . .buildkite/scripts/skip_if_only_docs_changes.sh
+      - make -C go build-fuzz
+    plugins:
+      <<: *docker_plugin
+
   # Wait for all jobs defined before this point
   # to finish running in parallel before continuing.
   - wait
diff --git a/.changelog/2695.internal.md b/.changelog/2695.internal.md
new file mode 100644
index 00000000000..517ae0889d7
--- /dev/null
+++ b/.changelog/2695.internal.md
@@ -0,0 +1 @@
+Make build-fuzz work again, test it on CI
diff --git a/go/consensus/tendermint/abci/mux_mock.go b/go/consensus/tendermint/abci/mux_mock.go
index 542d0c1dc7d..5d5a0886f7b 100644
--- a/go/consensus/tendermint/abci/mux_mock.go
+++ b/go/consensus/tendermint/abci/mux_mock.go
@@ -4,6 +4,8 @@ package abci
 
 import (
 	"context"
+
+	upgrade "github.com/oasislabs/oasis-core/go/upgrade/api"
 )
 
 // MockABCIMux exports some of the muxer's internal methods for testing use.
@@ -22,8 +24,8 @@ func (mux *MockABCIMux) MockClose() {
 }
 
 // NewMockMux creates a new ABCI mux suitable for testing.
-func NewMockMux(ctx context.Context, cfg *ApplicationConfig) (*MockABCIMux, error) {
-	mux, err := newABCIMux(ctx, cfg)
+func NewMockMux(ctx context.Context, upgrader upgrade.Backend, cfg *ApplicationConfig) (*MockABCIMux, error) {
+	mux, err := newABCIMux(ctx, upgrader, cfg)
 	if err != nil {
 		return nil, err
 	}
diff --git a/go/consensus/tendermint/apps/staking/proposing_rewards.go b/go/consensus/tendermint/apps/staking/proposing_rewards.go
index 4f3f20a46f9..ba44e8a0c26 100644
--- a/go/consensus/tendermint/apps/staking/proposing_rewards.go
+++ b/go/consensus/tendermint/apps/staking/proposing_rewards.go
@@ -41,7 +41,8 @@ func (app *stakingApplication) rewardBlockProposing(ctx *abci.Context, stakeStat
 	if err != nil {
 		return fmt.Errorf("app state getting current epoch: %w", err)
 	}
-	if epoch == epochtime.EpochInvalid {
+	invalidEpoch := epochtime.EpochInvalid // Workaround for incorrect go-fuzz instrumentation.
+	if epoch == invalidEpoch {
 		ctx.Logger().Info("rewardBlockProposing: this block does not belong to an epoch. no block proposing reward")
 		return nil
 	}
diff --git a/go/consensus/tendermint/fuzz/fuzz.go b/go/consensus/tendermint/fuzz/fuzz.go
index 2a0e1de6da4..189660bba09 100644
--- a/go/consensus/tendermint/fuzz/fuzz.go
+++ b/go/consensus/tendermint/fuzz/fuzz.go
@@ -16,6 +16,7 @@ import (
 	"github.com/oasislabs/oasis-core/go/consensus/tendermint/apps/epochtime_mock"
 	registryApp "github.com/oasislabs/oasis-core/go/consensus/tendermint/apps/registry"
 	stakingApp "github.com/oasislabs/oasis-core/go/consensus/tendermint/apps/staking"
+	"github.com/oasislabs/oasis-core/go/upgrade"
 )
 
 var (
@@ -53,7 +54,7 @@ func Fuzz(data []byte) int {
 	}
 
 	// The muxer will start with the previous state, if it exists (the state database isn't cleared).
-	muxer, _ := abci.NewMockMux(ctx, appConfig)
+	muxer, _ := abci.NewMockMux(ctx, upgrade.NewDummyUpgradeManager(), appConfig)
 	defer muxer.MockClose()
 
 	for _, app := range FuzzableApps {
diff --git a/go/storage/fuzz/fuzz.go b/go/storage/fuzz/fuzz.go
index ec3c3380865..5c59d436ea7 100644
--- a/go/storage/fuzz/fuzz.go
+++ b/go/storage/fuzz/fuzz.go
@@ -6,6 +6,7 @@ import (
 	"context"
 	"io/ioutil"
 
+	"github.com/oasislabs/oasis-core/go/common"
 	"github.com/oasislabs/oasis-core/go/common/crypto/signature"
 	"github.com/oasislabs/oasis-core/go/common/crypto/signature/signers/file"
 	commonFuzz "github.com/oasislabs/oasis-core/go/common/fuzz"
@@ -40,7 +41,7 @@ func init() {
 	}
 
 	// Create the storage backend service.
-	storageBackend, err = storage.New(context.Background(), localDB, identity, nil, nil)
+	storageBackend, err = storage.New(context.Background(), localDB, common.Namespace{}, identity, nil, nil)
 	if err != nil {
 		panic(err)
 	}
diff --git a/go/storage/fuzz/gencorpus/main.go b/go/storage/fuzz/gencorpus/main.go
index 6eff196e563..dccd7513370 100644
--- a/go/storage/fuzz/gencorpus/main.go
+++ b/go/storage/fuzz/gencorpus/main.go
@@ -9,6 +9,7 @@ import (
 	"fmt"
 	"io/ioutil"
 
+	"github.com/oasislabs/oasis-core/go/common"
 	commonFuzz "github.com/oasislabs/oasis-core/go/common/fuzz"
 	"github.com/oasislabs/oasis-core/go/common/identity"
 	"github.com/oasislabs/oasis-core/go/storage"
@@ -19,7 +20,7 @@ const (
 )
 
 func main() {
-	storage, err := storage.New(context.Background(), "/tmp/oasis-node-fuzz-storage", &identity.Identity{}, nil, nil)
+	storage, err := storage.New(context.Background(), "/tmp/oasis-node-fuzz-storage", common.Namespace{}, &identity.Identity{}, nil, nil)
 	if err != nil {
 		panic(err)
 	}