diff --git a/backend/Cargo.lock b/backend/Cargo.lock
index 8ada459..968a4d8 100644
--- a/backend/Cargo.lock
+++ b/backend/Cargo.lock
@@ -1033,6 +1033,7 @@ dependencies = [
  "tracing-subscriber",
  "twapi-ureq",
  "ureq",
+ "url 2.1.1",
  "uuid",
 ]
 
diff --git a/backend/Cargo.toml b/backend/Cargo.toml
index 9dc5f28..7b90fb6 100644
--- a/backend/Cargo.toml
+++ b/backend/Cargo.toml
@@ -9,27 +9,28 @@ edition = "2018"
 [dependencies]
 chrono = { version = "0.4", features = ["serde"] }
 color-eyre = "0.5"
-twapi-ureq = "0.1.5"
+futures-io = "0.3"
+hex = "0.4"
 kankyo = "0.3"
 log = "0.4"
 mime = "0.3.0"
 paseto = { version = "1.0", features = ["easy_tokens", "v2"] }
-ring = { version = "^0.16", features = ["std"] }
+prometheus = { version = "0.10", default-features = false, features = ["process"] }
 rand = "0"
+ring = { version = "^0.16", features = ["std"] }
+rocket = "0.4"
+rocket_prometheus = "0.7.0"
 rusty_ulid = "0.10"
 serde_json = "^1"
 serde = { version = "1", features = ["derive"] }
 thiserror = "1"
-rocket = "0.4"
 tracing = "0.1"
 tracing-log = "0.1"
 tracing-subscriber = "0.2"
+twapi-ureq = "0.1.5"
 ureq = { version = "1", features = ["json", "charset"] }
 uuid = { version = "0.7", features = ["serde", "v4"] }
-rocket_prometheus = "0.7.0"
-prometheus = { version = "0.10", default-features = false, features = ["process"] }
-futures-io = "0.3"
-hex = "0.4"
+url = "2"
 
 jsonfeed = { git = "https://github.com/Xe/site" }
 
diff --git a/backend/migrations/2020-11-04-163029_webmention-unique/down.sql b/backend/migrations/2020-11-04-163029_webmention-unique/down.sql
new file mode 100644
index 0000000..50c314d
--- /dev/null
+++ b/backend/migrations/2020-11-04-163029_webmention-unique/down.sql
@@ -0,0 +1 @@
+DROP INDEX webmentions_source_target;
diff --git a/backend/migrations/2020-11-04-163029_webmention-unique/up.sql b/backend/migrations/2020-11-04-163029_webmention-unique/up.sql
new file mode 100644
index 0000000..757eee5
--- /dev/null
+++ b/backend/migrations/2020-11-04-163029_webmention-unique/up.sql
@@ -0,0 +1,2 @@
+CREATE UNIQUE INDEX webmentions_source_target
+  ON webmentions(source_url, target_url);
diff --git a/backend/src/api/mod.rs b/backend/src/api/mod.rs
index 443f717..2095adb 100644
--- a/backend/src/api/mod.rs
+++ b/backend/src/api/mod.rs
@@ -13,6 +13,7 @@ use rocket_contrib::json::Json;
 use std::io::Read;
 
 pub mod switch;
+pub mod webmention;
 
 #[get("/members")]
 #[instrument(skip(conn), err)]
@@ -79,6 +80,12 @@ pub enum Error {
 
     #[error("web API interop error: {0}")]
     Web(#[from] web::Error),
+
+    #[error("URL parsing error: {0}")]
+    URL(#[from] url::ParseError),
+
+    #[error("invalid webmention: {0}")]
+    InvalidWebMention(String),
 }
 
 pub type Result<T = ()> = std::result::Result<T, Error>;
@@ -88,6 +95,7 @@ impl<'a> Responder<'a> for Error {
         error!("{}", self);
         match self {
             Error::NotFound => Err(Status::NotFound),
+            Error::InvalidWebMention(_) => Err(Status::BadRequest),
             _ => Err(Status::InternalServerError),
         }
     }
diff --git a/backend/src/api/webmention.rs b/backend/src/api/webmention.rs
new file mode 100644
index 0000000..62e7106
--- /dev/null
+++ b/backend/src/api/webmention.rs
@@ -0,0 +1,107 @@
+use super::{Error, Result};
+use crate::{models, schema, MainDatabase};
+use diesel::prelude::*;
+use rocket::{
+    request::Form,
+    response::{self, Responder},
+    Request, Response,
+};
+use rocket_contrib::json::Json;
+use rusty_ulid::generate_ulid_string;
+use url::Url;
+
+#[derive(FromForm, Debug)]
+pub struct WebMention {
+    source: String,
+    target: String,
+}
+
+impl WebMention {
+    fn check(&self) -> Result {
+        if self.source == self.target {
+            return Err(Error::InvalidWebMention("source == target".into()));
+        }
+
+        let u: Url = Url::parse(&self.source)?;
+        match u.scheme() {
+            "http" | "https" => {}
+            _ => return Err(Error::InvalidWebMention("invalid source scheme".into())),
+        }
+
+        u.host_str()
+            .ok_or(Error::InvalidWebMention("no host found in target".into()))?;
+
+        let u: Url = Url::parse(&self.target)?;
+        match u.scheme() {
+            "http" | "https" => {}
+            _ => return Err(Error::InvalidWebMention("invalid target scheme".into())),
+        }
+
+        match u
+            .host_str()
+            .ok_or(Error::InvalidWebMention("no host found in target".into()))?
+        {
+            "christine.website" | "cetacean.club" => {}
+            _ => return Err(Error::InvalidWebMention("invalid target host".into())),
+        }
+
+        Ok(())
+    }
+}
+
+impl Into<models::WebMention> for WebMention {
+    fn into(self) -> models::WebMention {
+        models::WebMention {
+            id: generate_ulid_string(),
+            source_url: self.source,
+            target_url: self.target,
+        }
+    }
+}
+
+impl<'a> Responder<'a> for models::WebMention {
+    fn respond_to(self, _: &Request) -> response::Result<'a> {
+        Response::build()
+            .raw_header(
+                "Location",
+                format!("https://mi.christine.website/api/webmention/{}", self.id),
+            )
+            .ok()
+    }
+}
+
+#[post("/webmention/accept", data = "<mention>")]
+#[instrument(skip(conn, mention), err)]
+pub fn accept(conn: MainDatabase, mention: Form<WebMention>) -> Result<models::WebMention> {
+    use schema::webmentions;
+
+    let mention = mention.into_inner();
+    mention.check()?;
+
+    info!(
+        source = &mention.source[..],
+        target = &mention.target[..],
+        "webmention received"
+    );
+
+    let wm: models::WebMention = mention.into();
+    diesel::insert_into(webmentions::table)
+        .values(&wm)
+        .execute(&*conn)
+        .map_err(Error::Database)?;
+
+    Ok(wm)
+}
+
+#[get("/webmention/<mention_id>")]
+#[instrument(skip(conn), err)]
+pub fn get(conn: MainDatabase, mention_id: String) -> Result<Json<models::WebMention>> {
+    use schema::webmentions::dsl::webmentions;
+
+    Ok(Json(
+        webmentions
+            .find(mention_id)
+            .get_result(&*conn)
+            .map_err(Error::Database)?,
+    ))
+}
diff --git a/backend/src/main.rs b/backend/src/main.rs
index 3cf532b..adf88f4 100644
--- a/backend/src/main.rs
+++ b/backend/src/main.rs
@@ -57,6 +57,8 @@ fn main() -> Result<()> {
                 api::switch::get,
                 api::switch::list,
                 api::switch::switch,
+                api::webmention::accept,
+                api::webmention::get,
                 api::get_members,
                 api::token_info,
                 api::tweet,
diff --git a/backend/src/models.rs b/backend/src/models.rs
index 7773ff5..2177f3f 100644
--- a/backend/src/models.rs
+++ b/backend/src/models.rs
@@ -50,3 +50,11 @@ pub struct NewSwitch {
 pub struct UpdateSwitchTime {
     pub ended_at: Option<NaiveDateTime>,
 }
+
+#[derive(Queryable, Associations, Insertable, Serialize)]
+#[table_name = "webmentions"]
+pub struct WebMention {
+    pub id: String,
+    pub source_url: String,
+    pub target_url: String,
+}