diff --git a/Makefile b/Makefile
index 6f137d8..d158c58 100644
--- a/Makefile
+++ b/Makefile
@@ -2,7 +2,7 @@
 all: honk
 
 honk: *.go
-	go build -o honk
+	go build -mod=`ls -d vendor 2> /dev/null` -o honk
 
 clean:
 	rm -f honk
diff --git a/README b/README
index 4e82446..8741057 100644
--- a/README
+++ b/README
@@ -14,20 +14,23 @@ The button to submit a new honk says "it's gonna be honked".
 
 Ein Honk is a stupid person auf deutsch.
 
--- requirements
+-- build
 
-github.com/gorilla/mux
-golang.org/x/crypto
-golang.org/x/net
-golang.org/x/text
-humungus.tedunangst.com/r/go-sqlite3
-
-It should be sufficient to type make after unpacking a release under go/src.
-Mind your gopath.
+It should be sufficient to type make after unpacking a release.
+You'll need a go compiler version 1.11 or later.
 
 Even on a fast machine, building from source can take several seconds.
 
-Busy honk instances may require megabytes of memory.
+-- requirements
+
+libsqlite3 (you probably already have it)
+
+go modules included in vendor:
+github.com/gorilla/mux
+golang.org/x/crypto
+golang.org/x/net
+golang.org/x/sys
+humungus.tedunangst.com/r/go-sqlite3
 
 -- setup
 
@@ -47,3 +50,4 @@ Then run honk.
 
 ./honk
 
+Busy honk instances may use megabytes of memory.
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..689e8df
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,9 @@
+module humungus.tedunangst.com/r/honk
+
+require (
+	github.com/gorilla/mux v1.7.1
+	golang.org/x/crypto v0.0.0-20190404164418-38d8ce5564a5
+	golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3
+	golang.org/x/sys v0.0.0-20190403152447-81d4e9dc473e
+	humungus.tedunangst.com/r/go-sqlite3 v1.1.2
+)
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..f4da27a
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,13 @@
+github.com/gorilla/mux v1.7.1 h1:Dw4jY2nghMMRsh1ol8dv1axHkDwMQK2DHerMNJsIpJU=
+github.com/gorilla/mux v1.7.1/go.mod h1:1lud6UwP+6orDFRuTfBEV8e9/aOM/c4fVVCaMa2zaAs=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20190404164418-38d8ce5564a5 h1:bselrhR0Or1vomJZC8ZIjWtbDmn9OYFLX5Ik9alpJpE=
+golang.org/x/crypto v0.0.0-20190404164418-38d8ce5564a5/go.mod h1:WFFai1msRO1wXaEeE5yQxYXgSfI8pQAWXbQop6sCtWE=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3 h1:0GoQqolDA55aaLxZyTzK/Y2ePZzZTUrRacwib7cNsYQ=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190403152447-81d4e9dc473e h1:nFYrTHrdrAOpShe27kaFHjsqYSEQ0KWqdWLu3xuZJts=
+golang.org/x/sys v0.0.0-20190403152447-81d4e9dc473e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+humungus.tedunangst.com/r/go-sqlite3 v1.1.2 h1:bRAXNRZ4VNFRFhhG4tdudK4Lv4ktHQAHEppKlDANUFg=
+humungus.tedunangst.com/r/go-sqlite3 v1.1.2/go.mod h1:FtEEmQM7U2Ey1TuEEOyY1BmphTZnmiEjPsNLEAkpf/M=