diff --git a/.gitea/workflows/release-keeper-ziren.yml b/.gitea/workflows/release-keeper-ziren.yml
deleted file mode 100644
index 63557b52dc..0000000000
--- a/.gitea/workflows/release-keeper-ziren.yml
+++ /dev/null
@@ -1,31 +0,0 @@
-on:
-  push:
-    branches:
-      - "master"
-    tags:
-      - "v*"
-  workflow_dispatch:
-
-jobs:
-  keeper-ziren:
-    name: Keeper ZKVM Build
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v4
-
-    - name: Set up Go
-      uses: actions/setup-go@v5
-      with:
-        go-version: 1.25
-        cache: false
-
-    - name: Install cross toolchain for MIPS
-      run: |
-        apt-get update
-        apt-get -yq --no-install-suggests --no-install-recommends install gcc-mipsel-linux-gnu libc6-dev-mipsel-cross
-
-    - name: Build keeper with ziren tag (mipsle)
-      run: |
-        go run build/ci.go install -static -arch mipsle -os linux -cc mipsel-linux-gnu-gcc -tags ziren -dlgo ./cmd/keeper
-      env:
-        GOMIPS: "softfloat"
diff --git a/build/ci.go b/build/ci.go
index f60ac6e59c..71d18ce5e5 100644
--- a/build/ci.go
+++ b/build/ci.go
@@ -214,16 +214,14 @@ func doInstall(cmdline []string) {
 	var (
 		dlgo       = flag.Bool("dlgo", false, "Download Go and build with it")
 		arch       = flag.String("arch", "", "Architecture to cross build for")
-		goos       = flag.String("os", "", "Operating system to cross build for")
 		cc         = flag.String("cc", "", "C compiler to cross build with")
 		staticlink = flag.Bool("static", false, "Create statically-linked executable")
-		tags       = flag.String("tags", "", "Additional build tags (comma-separated)")
 	)
 	flag.CommandLine.Parse(cmdline)
 	env := build.Env()
 
 	// Configure the toolchain.
-	tc := build.GoToolchain{GOARCH: *arch, GOOS: *goos, CC: *cc}
+	tc := build.GoToolchain{GOARCH: *arch, CC: *cc}
 	if *dlgo {
 		csdb := download.MustLoadChecksums("build/checksums.txt")
 		tc.Root = build.DownloadGo(csdb)
@@ -236,20 +234,6 @@ func doInstall(cmdline []string) {
 		buildTags = append(buildTags, "ckzg")
 	}
 
-	// Add custom tags if provided
-	if *tags != "" {
-		// Split by both comma and whitespace
-		customTags := strings.FieldsFunc(*tags, func(r rune) bool {
-			return r == ',' || r == ' ' || r == '\t'
-		})
-		for _, tag := range customTags {
-			tag = strings.TrimSpace(tag)
-			if tag != "" {
-				buildTags = append(buildTags, tag)
-			}
-		}
-	}
-
 	// Configure the build.
 	gobuild := tc.Go("build", buildFlags(env, *staticlink, buildTags)...)