diff --git a/build/fietsje/deps_cilium.go b/build/fietsje/deps_cilium.go
new file mode 100644
index 0000000..d4d9e19
--- /dev/null
+++ b/build/fietsje/deps_cilium.go
@@ -0,0 +1,78 @@
+// Copyright 2020 The Monogon Project Authors.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+func depsCilium(p *planner) {
+	p.collect(
+		"github.com/cilium/cilium", "v1.8.0-rc1",
+		disabledProtoBuild,
+	).replace(
+		// Cilium forks this library to introduce an API that they need, but
+		// which the upstream rejected. Since this new API does not cause any
+		// backwards incompatibility, we pull in their fork.
+		// See https://github.com/miekg/dns/pull/949#issuecomment-487832458 for
+		// more information about the fork.
+		"github.com/miekg/dns", "github.com/cilium/dns", "8e25ec9a0ff3",
+	).replace(
+		// Cilium forks this library (a Go Kafka client) to apply the following
+		// patches on top:
+		//   - 01ce283: Fix de/serialization of null arrays
+		//   - c411825: Correcly check msgSize in ReadResp before discarding.
+		//   - 947cc36: Kafka : Cilium panics with error *index out of range
+		//              error* on receiving messages of very large size.
+		// serge@ has not found any trace of the Cilium project trying to
+		// upstream this, but the patches seem to be only bugfixes, not
+		// breaking functionality.
+		// However, the fork-off point of the upstream project is fairly old
+		// (commit b5a758db, dated Dec 7, 2017 - pre v1.5.0 of upstream). This
+		// might cause issues in the future when we start to have other
+		// consumers of this library.
+		"github.com/optiopay/kafka", "github.com/cilium/kafka", "01ce283b732b",
+	).use(
+		"github.com/hashicorp/go-immutable-radix",
+		"github.com/sasha-s/go-deadlock",
+		"github.com/google/gopacket",
+		"github.com/hashicorp/consul/api",
+		"github.com/pborman/uuid",
+		"github.com/petermattis/goid",
+		"github.com/kr/text",
+		"github.com/hashicorp/go-cleanhttp",
+		"github.com/hashicorp/serf",
+		"github.com/envoyproxy/protoc-gen-validate",
+		"github.com/hashicorp/go-rootcerts",
+		"github.com/armon/go-metrics",
+		"github.com/shirou/gopsutil",
+		"github.com/cncf/udpa/go",
+		"github.com/cpuguy83/go-md2man/v2",
+		"github.com/russross/blackfriday/v2",
+		"github.com/shurcooL/sanitized_anchor_name",
+		"github.com/google/gops",
+		"github.com/mattn/go-shellwords",
+		"github.com/c9s/goprocinfo",
+		"github.com/cilium/ipam",
+		"github.com/kardianos/osext",
+		"github.com/servak/go-fastping",
+		"github.com/golang/snappy",
+		"github.com/cilium/arping",
+	).with(disabledProtoBuild, forceBazelGeneration).use(
+		"github.com/cilium/proxy",
+	).with(disabledProtoBuild, buildExtraArgs("-exclude=src")).use(
+		// -exclude=src fixes a build issue with Gazelle. See:
+		// https://github.com/census-instrumentation/opencensus-proto/issues/200
+		"github.com/census-instrumentation/opencensus-proto",
+	)
+}