diff --git a/backend/Cargo.lock b/backend/Cargo.lock
index e91df26..3de45a2 100644
--- a/backend/Cargo.lock
+++ b/backend/Cargo.lock
@@ -1023,12 +1023,26 @@ dependencies = [
 
 [[package]]
 name = "proc-macro-error"
-version = "0.2.6"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro-error-attr 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustversion 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "proc-macro-error-attr"
+version = "0.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustversion 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "syn 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn-mid 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1283,6 +1297,16 @@ dependencies = [
  "webpki 0.19.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "rustversion"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro2 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "ryu"
 version = "1.0.0"
@@ -1428,20 +1452,20 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "structopt"
-version = "0.3.3"
+version = "0.3.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "structopt-derive 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "structopt-derive 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "structopt-derive"
-version = "0.3.3"
+version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "heck 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "proc-macro-error 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro-error 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "proc-macro2 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "syn 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1467,6 +1491,16 @@ dependencies = [
  "unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "syn-mid"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro2 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "synstructure"
 version = "0.10.2"
@@ -1925,7 +1959,7 @@ dependencies = [
  "serde 1.0.101 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_derive 1.0.101 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_json 1.0.41 (registry+https://github.com/rust-lang/crates.io-index)",
- "structopt 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "structopt 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "time-cache 0.1.0",
 ]
 
@@ -2034,7 +2068,8 @@ dependencies = [
 "checksum percent-encoding 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d4fd5641d01c8f18a23da7b6fe29298ff4b55afcccdf78973b24cf3175fee32e"
 "checksum ppv-lite86 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)" = "e3cbf9f658cdb5000fcf6f362b8ea2ba154b9f146a61c7a20d647034c6b6561b"
 "checksum pretty_env_logger 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "717ee476b1690853d222af4634056d830b5197ffd747726a9a1eee6da9f49074"
-"checksum proc-macro-error 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "aeccfe4d5d8ea175d5f0e4a2ad0637e0f4121d63bd99d356fb1f39ab2e7c6097"
+"checksum proc-macro-error 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)" = "53c98547ceaea14eeb26fcadf51dc70d01a2479a7839170eae133721105e4428"
+"checksum proc-macro-error-attr 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)" = "c2bf5d493cf5d3e296beccfd61794e445e830dfc8070a9c248ad3ee071392c6c"
 "checksum proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)" = "cf3d2011ab5c909338f7887f4fc896d35932e29146c12c8d01da6b22a80ba759"
 "checksum proc-macro2 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "4c5c2380ae88876faae57698be9e9775e3544decad214599c3a6266cca6ac802"
 "checksum quick-error 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "9274b940887ce9addde99c4eee6b5c44cc494b182b97e73dc8ffdcb3397fd3f0"
@@ -2063,6 +2098,7 @@ dependencies = [
 "checksum rustc-demangle 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)" = "a7f4dccf6f4891ebcc0c39f9b6eb1a83b9bf5d747cb439ec6fba4f3b977038af"
 "checksum rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "138e3e0acb6c9fb258b19b67cb8abd63c00679d2851805ea151465464fe9030a"
 "checksum rustls 0.15.2 (registry+https://github.com/rust-lang/crates.io-index)" = "f271e3552cd835fa28c541c34a7e8fdd8cdff09d77fe4eb8f6c42e87a11b096e"
+"checksum rustversion 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c48f91977f4ef3be5358c15d131d3f663f6b4d7a112555bf3bf52ad23b6659e5"
 "checksum ryu 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c92464b447c0ee8c4fb3824ecc8383b81717b9f1e74ba2e72540aef7b9f82997"
 "checksum scopeguard 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "94258f53601af11e6a49f722422f6e3425c52b06245a5cf9bc09908b174f5e27"
 "checksum scopeguard 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b42e15e59b18a828bbf5c58ea01debb36b9b096346de35d941dcb89009f24a0d"
@@ -2083,10 +2119,11 @@ dependencies = [
 "checksum stable_deref_trait 1.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "dba1a27d3efae4351c8051072d619e3ade2820635c3958d826bfea39d59b54c8"
 "checksum string 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "d24114bfcceb867ca7f71a0d3fe45d45619ec47a6fbfa98cb14e14250bfa5d6d"
 "checksum strsim 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
-"checksum structopt 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "6d4f66a4c0ddf7aee4677995697366de0749b0139057342eccbb609b12d0affc"
-"checksum structopt-derive 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "8fe0c13e476b4e21ff7f5c4ace3818b6d7bdc16897c31c73862471bc1663acae"
+"checksum structopt 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)" = "884ae79d6aad1e738f4a70dff314203fd498490a63ebc4d03ea83323c40b7b72"
+"checksum structopt-derive 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "0a97f829a34a0a9d5b353a881025a23b8c9fd09d46be6045df6b22920dbd7a93"
 "checksum syn 0.15.41 (registry+https://github.com/rust-lang/crates.io-index)" = "5f48d3b9d3d5ee64217007ead81e80d40674c80e930cf53ed089f0f809fae31e"
 "checksum syn 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "158521e6f544e7e3dcfc370ac180794aa38cb34a1b1e07609376d4adcf429b93"
+"checksum syn-mid 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "9fd3937748a7eccff61ba5b90af1a20dbf610858923a9192ea0ecb0cb77db1d0"
 "checksum synstructure 0.10.2 (registry+https://github.com/rust-lang/crates.io-index)" = "02353edf96d6e4dc81aea2d8490a7e9db177bf8acb0e951c24940bf866cb313f"
 "checksum termcolor 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)" = "96d6098003bde162e4277c70665bd87c326f5a0c3f3fbfb285787fa482d54e6e"
 "checksum textwrap 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d326610f408c7a4eb6f51c37c330e496b08506c9457c9d34287ecc38809fb060"
diff --git a/backend/Cargo.toml b/backend/Cargo.toml
index 937eacd..e9083c7 100644
--- a/backend/Cargo.toml
+++ b/backend/Cargo.toml
@@ -19,5 +19,5 @@ pretty_env_logger = "0.3.1"
 serde = { version = "1.0.101", features = ["rc"] }
 serde_derive = "1.0.101"
 serde_json = "1.0.41"
-structopt = "0.3.3"
+structopt = "0.3.7"
 time-cache = { path = "../time-cache" }