diff --git a/go.mod b/go.mod
index d1cefcf78..65dcf0490 100644
--- a/go.mod
+++ b/go.mod
@@ -7,7 +7,7 @@ require (
 	github.com/cpuguy83/go-md2man/v2 v2.0.0 // indirect
 	github.com/gin-contrib/sessions v0.0.3
 	github.com/gin-gonic/gin v1.6.3
-	github.com/go-fed/activity v1.0.0
+	github.com/go-fed/activity v1.0.1-0.20210426194615-e0de0863dcc1
 	github.com/go-fed/httpsig v0.1.1-0.20190914113940-c2de3672e5b5
 	github.com/go-pg/pg/extra/pgdebug v0.2.0
 	github.com/go-pg/pg/v10 v10.8.0
diff --git a/go.sum b/go.sum
index 7a8514c2a..341494d79 100644
--- a/go.sum
+++ b/go.sum
@@ -59,8 +59,8 @@ github.com/globalsign/mgo v0.0.0-20181015135952-eeefdecb41b8/go.mod h1:xkRDCp4j0
 github.com/go-errors/errors v1.0.1/go.mod h1:f4zRHt4oKfwPJE5k8C9vpYG+aDHdBFUsgrm6/TyX73Q=
 github.com/go-errors/errors v1.0.2 h1:xMxH9j2fNg/L4hLn/4y3M0IUsn0M6Wbu/Uh9QlOfBh4=
 github.com/go-errors/errors v1.0.2/go.mod h1:psDX2osz5VnTOnFWbDeWwS7yejl+uV3FEWEp4lssFEs=
-github.com/go-fed/activity v1.0.0 h1:j7w3auHZnVCjUcgA1mE+UqSOjFBhvW2Z2res3vNol+o=
-github.com/go-fed/activity v1.0.0/go.mod h1:v4QoPaAzjWZ8zN2VFVGL5ep9C02mst0hQYHUpQwso4Q=
+github.com/go-fed/activity v1.0.1-0.20210426194615-e0de0863dcc1 h1:go9MogQW0eTLwdOs/ZfNCGpwUkVcr7IMUbI3u8wYQxw=
+github.com/go-fed/activity v1.0.1-0.20210426194615-e0de0863dcc1/go.mod h1:v4QoPaAzjWZ8zN2VFVGL5ep9C02mst0hQYHUpQwso4Q=
 github.com/go-fed/httpsig v0.1.1-0.20190914113940-c2de3672e5b5 h1:WLvFZqoXnuVTBKA6U/1FnEHNQ0Rq0QM0rGhY8Tx6R1g=
 github.com/go-fed/httpsig v0.1.1-0.20190914113940-c2de3672e5b5/go.mod h1:T56HUNYZUQ1AGUzhAYPugZfp36sKApVnGBgKlIY+aIE=
 github.com/go-pg/pg/extra/pgdebug v0.2.0 h1:t62UhMiV6KYAxSWojwIJiyX06TdepkzCeIzdeb00184=
diff --git a/internal/api/s2s/user/inboxpost.go b/internal/api/s2s/user/inboxpost.go
new file mode 100644
index 000000000..7be36590a
--- /dev/null
+++ b/internal/api/s2s/user/inboxpost.go
@@ -0,0 +1,56 @@
+/*
+   GoToSocial
+   Copyright (C) 2021 GoToSocial Authors admin@gotosocial.org
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Affero General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Affero General Public License for more details.
+
+   You should have received a copy of the GNU Affero General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package user
+
+import (
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+	"github.com/sirupsen/logrus"
+	"github.com/superseriousbusiness/gotosocial/internal/message"
+)
+
+func (m *Module) InboxPOSTHandler(c *gin.Context) {
+	l := m.log.WithFields(logrus.Fields{
+		"func": "InboxPOSTHandler",
+		"url":  c.Request.RequestURI,
+	})
+
+	requestedUsername := c.Param(UsernameKey)
+	if requestedUsername == "" {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "no username specified in request"})
+		return
+	}
+
+	posted, err := m.processor.InboxPost(c.Request.Context(), c.Writer, c.Request)
+	if err != nil {
+		if withCode, ok := err.(message.ErrorWithCode); ok {
+			l.Debug(withCode.Error())
+			c.JSON(withCode.Code(), withCode.Safe())
+			return
+		}
+		l.Debug(err)
+		c.JSON(http.StatusBadRequest, gin.H{"error": "unable to process request"})
+		return
+	}
+
+	if !posted {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "unable to process request"})
+	}
+}
diff --git a/internal/api/s2s/user/user.go b/internal/api/s2s/user/user.go
index 693fac7c3..36c1389d1 100644
--- a/internal/api/s2s/user/user.go
+++ b/internal/api/s2s/user/user.go
@@ -38,6 +38,7 @@ const (
 	// Use this anywhere you need to know the username of the user being queried.
 	// Eg https://example.org/users/:username
 	UsersBasePathWithUsername = UsersBasePath + "/:" + UsernameKey
+	UsersInboxPath            = UsersBasePathWithUsername + "/" + util.InboxPath
 )
 
 // ActivityPubAcceptHeaders represents the Accept headers mentioned here:
@@ -66,5 +67,6 @@ func New(config *config.Config, processor message.Processor, log *logrus.Logger)
 // Route satisfies the RESTAPIModule interface
 func (m *Module) Route(s router.Router) error {
 	s.AttachHandler(http.MethodGet, UsersBasePathWithUsername, m.UsersGETHandler)
+	s.AttachHandler(http.MethodPost, UsersInboxPath, m.InboxPOSTHandler)
 	return nil
 }
diff --git a/internal/db/federating_db.go b/internal/db/federating_db.go
index ab66b19de..50f74b407 100644
--- a/internal/db/federating_db.go
+++ b/internal/db/federating_db.go
@@ -104,6 +104,13 @@ func (f *federatingDB) Unlock(c context.Context, id *url.URL) error {
 //
 // The library makes this call only after acquiring a lock first.
 func (f *federatingDB) InboxContains(c context.Context, inbox, id *url.URL) (contains bool, err error) {
+	l := f.log.WithFields(
+		logrus.Fields{
+			"func": "InboxContains",
+			"id": id.String(),
+		},
+	)
+	l.Debug("entering INBOXCONTAINS function")
 
 	if !util.IsInboxPath(inbox) {
 		return false, fmt.Errorf("%s is not an inbox URI", inbox.String())
@@ -151,6 +158,14 @@ func (f *federatingDB) SetInbox(c context.Context, inbox vocab.ActivityStreamsOr
 // the database has an entry for the IRI.
 // The library makes this call only after acquiring a lock first.
 func (f *federatingDB) Owns(c context.Context, id *url.URL) (bool, error) {
+	l := f.log.WithFields(
+		logrus.Fields{
+			"func": "Owns",
+			"id": id.String(),
+		},
+	)
+	l.Debug("entering OWNS function")
+
 	// if the id host isn't this instance host, we don't own this IRI
 	if id.Host != f.config.Host {
 		return false, nil
@@ -199,6 +214,14 @@ func (f *federatingDB) Owns(c context.Context, id *url.URL) (bool, error) {
 //
 // The library makes this call only after acquiring a lock first.
 func (f *federatingDB) ActorForOutbox(c context.Context, outboxIRI *url.URL) (actorIRI *url.URL, err error) {
+	l := f.log.WithFields(
+		logrus.Fields{
+			"func": "ActorForOutbox",
+			"inboxIRI": outboxIRI.String(),
+		},
+	)
+	l.Debug("entering ACTORFOROUTBOX function")
+
 	if !util.IsOutboxPath(outboxIRI) {
 		return nil, fmt.Errorf("%s is not an outbox URI", outboxIRI.String())
 	}
@@ -216,6 +239,14 @@ func (f *federatingDB) ActorForOutbox(c context.Context, outboxIRI *url.URL) (ac
 //
 // The library makes this call only after acquiring a lock first.
 func (f *federatingDB) ActorForInbox(c context.Context, inboxIRI *url.URL) (actorIRI *url.URL, err error) {
+	l := f.log.WithFields(
+		logrus.Fields{
+			"func": "ActorForInbox",
+			"inboxIRI": inboxIRI.String(),
+		},
+	)
+	l.Debug("entering ACTORFORINBOX function")
+
 	if !util.IsInboxPath(inboxIRI) {
 		return nil, fmt.Errorf("%s is not an inbox URI", inboxIRI.String())
 	}
@@ -234,6 +265,14 @@ func (f *federatingDB) ActorForInbox(c context.Context, inboxIRI *url.URL) (acto
 //
 // The library makes this call only after acquiring a lock first.
 func (f *federatingDB) OutboxForInbox(c context.Context, inboxIRI *url.URL) (outboxIRI *url.URL, err error) {
+	l := f.log.WithFields(
+		logrus.Fields{
+			"func": "OutboxForInbox",
+			"inboxIRI": inboxIRI.String(),
+		},
+	)
+	l.Debug("entering OUTBOXFORINBOX function")
+
 	if !util.IsInboxPath(inboxIRI) {
 		return nil, fmt.Errorf("%s is not an inbox URI", inboxIRI.String())
 	}
@@ -252,6 +291,14 @@ func (f *federatingDB) OutboxForInbox(c context.Context, inboxIRI *url.URL) (out
 //
 // The library makes this call only after acquiring a lock first.
 func (f *federatingDB) Exists(c context.Context, id *url.URL) (exists bool, err error) {
+	l := f.log.WithFields(
+		logrus.Fields{
+			"func": "Exists",
+			"id": id.String(),
+		},
+	)
+	l.Debug("entering EXISTS function")
+
 	return false, nil
 }
 
@@ -259,6 +306,13 @@ func (f *federatingDB) Exists(c context.Context, id *url.URL) (exists bool, err
 //
 // The library makes this call only after acquiring a lock first.
 func (f *federatingDB) Get(c context.Context, id *url.URL) (value vocab.Type, err error) {
+	l := f.log.WithFields(
+		logrus.Fields{
+			"func": "Get",
+			"id": id.String(),
+		},
+	)
+	l.Debug("entering GET function")
 	return nil, nil
 }
 
@@ -275,6 +329,13 @@ func (f *federatingDB) Get(c context.Context, id *url.URL) (value vocab.Type, er
 // Under certain conditions and network activities, Create may be called
 // multiple times for the same ActivityStreams object.
 func (f *federatingDB) Create(c context.Context, asType vocab.Type) error {
+	l := f.log.WithFields(
+		logrus.Fields{
+			"func": "Create",
+			"asType": asType.GetTypeName(),
+		},
+	)
+	l.Debugf("received CREATE asType %+v", asType)
 	return nil
 }
 
@@ -288,6 +349,13 @@ func (f *federatingDB) Create(c context.Context, asType vocab.Type) error {
 //
 // The library makes this call only after acquiring a lock first.
 func (f *federatingDB) Update(c context.Context, asType vocab.Type) error {
+	l := f.log.WithFields(
+		logrus.Fields{
+			"func": "Update",
+			"asType": asType.GetTypeName(),
+		},
+	)
+	l.Debugf("received UPDATE asType %+v", asType)
 	return nil
 }
 
@@ -298,6 +366,13 @@ func (f *federatingDB) Update(c context.Context, asType vocab.Type) error {
 //
 // The library makes this call only after acquiring a lock first.
 func (f *federatingDB) Delete(c context.Context, id *url.URL) error {
+	l := f.log.WithFields(
+		logrus.Fields{
+			"func": "Delete",
+			"id": id.String(),
+		},
+	)
+	l.Debugf("received DELETE id %s", id.String())
 	return nil
 }
 
@@ -325,6 +400,14 @@ func (f *federatingDB) SetOutbox(c context.Context, outbox vocab.ActivityStreams
 // The go-fed library will handle setting the 'id' property on the
 // activity or object provided with the value returned.
 func (f *federatingDB) NewID(c context.Context, t vocab.Type) (id *url.URL, err error) {
+
+	l := f.log.WithFields(
+		logrus.Fields{
+			"func": "NewID",
+			"asType": t.GetTypeName(),
+		},
+	)
+	l.Debugf("received NEWID request for asType %+v", t)
 	return nil, nil
 }
 
diff --git a/internal/federation/commonbehavior.go b/internal/federation/commonbehavior.go
index 9274e78b4..8ed6fd2cb 100644
--- a/internal/federation/commonbehavior.go
+++ b/internal/federation/commonbehavior.go
@@ -57,7 +57,7 @@ import (
 // authenticated must be true and error nil. The request will continue
 // to be processed.
 func (f *federator) AuthenticateGetInbox(ctx context.Context, w http.ResponseWriter, r *http.Request) (context.Context, bool, error) {
-	// IMPLEMENTATION NOTE: For GoToSocial, we serve outboxes and inboxes through
+	// IMPLEMENTATION NOTE: For GoToSocial, we serve GETS to outboxes and inboxes through
 	// the CLIENT API, not through the federation API, so we just do nothing here.
 	return nil, false, nil
 }
@@ -82,7 +82,7 @@ func (f *federator) AuthenticateGetInbox(ctx context.Context, w http.ResponseWri
 // authenticated must be true and error nil. The request will continue
 // to be processed.
 func (f *federator) AuthenticateGetOutbox(ctx context.Context, w http.ResponseWriter, r *http.Request) (context.Context, bool, error) {
-	// IMPLEMENTATION NOTE: For GoToSocial, we serve outboxes and inboxes through
+	// IMPLEMENTATION NOTE: For GoToSocial, we serve GETS to outboxes and inboxes through
 	// the CLIENT API, not through the federation API, so we just do nothing here.
 	return nil, false, nil
 }
@@ -96,7 +96,7 @@ func (f *federator) AuthenticateGetOutbox(ctx context.Context, w http.ResponseWr
 // Always called, regardless whether the Federated Protocol or Social
 // API is enabled.
 func (f *federator) GetOutbox(ctx context.Context, r *http.Request) (vocab.ActivityStreamsOrderedCollectionPage, error) {
-	// IMPLEMENTATION NOTE: For GoToSocial, we serve outboxes and inboxes through
+	// IMPLEMENTATION NOTE: For GoToSocial, we serve GETS to outboxes and inboxes through
 	// the CLIENT API, not through the federation API, so we just do nothing here.
 	return nil, nil
 }
diff --git a/internal/federation/federatingactor.go b/internal/federation/federatingactor.go
index f105d9125..65a16efaf 100644
--- a/internal/federation/federatingactor.go
+++ b/internal/federation/federatingactor.go
@@ -77,6 +77,13 @@ func (f *federatingActor) PostInbox(c context.Context, w http.ResponseWriter, r
 	return f.actor.PostInbox(c, w, r)
 }
 
+// PostInboxScheme is similar to PostInbox, except clients are able to
+// specify which protocol scheme to handle the incoming request and the
+// data stored within the application (HTTP, HTTPS, etc).
+func (f *federatingActor) PostInboxScheme(c context.Context, w http.ResponseWriter, r *http.Request, scheme string) (bool, error) {
+	return f.actor.PostInboxScheme(c, w, r, scheme)
+}
+
 // GetInbox returns true if the request was handled as an ActivityPub
 // GET to an actor's inbox. If false, the request was not an ActivityPub
 // request and may still be handled by the caller in another way, such
@@ -118,6 +125,13 @@ func (f *federatingActor) PostOutbox(c context.Context, w http.ResponseWriter, r
 	return f.actor.PostOutbox(c, w, r)
 }
 
+// PostOutboxScheme is similar to PostOutbox, except clients are able to
+// specify which protocol scheme to handle the incoming request and the
+// data stored within the application (HTTP, HTTPS, etc).
+func (f *federatingActor) PostOutboxScheme(c context.Context, w http.ResponseWriter, r *http.Request, scheme string) (bool, error) {
+	return f.actor.PostOutboxScheme(c, w, r, scheme)
+}
+
 // GetOutbox returns true if the request was handled as an ActivityPub
 // GET to an actor's outbox. If false, the request was not an
 // ActivityPub request.
diff --git a/internal/federation/federatingprotocol.go b/internal/federation/federatingprotocol.go
index 1764eb791..22769317a 100644
--- a/internal/federation/federatingprotocol.go
+++ b/internal/federation/federatingprotocol.go
@@ -72,6 +72,7 @@ func (f *federator) PostInboxRequestBodyHook(ctx context.Context, r *http.Reques
 		return nil, err
 	}
 
+
 	ctxWithActivity := context.WithValue(ctx, util.APActivity, activity)
 	return ctxWithActivity, nil
 }
@@ -100,14 +101,22 @@ func (f *federator) AuthenticatePostInbox(ctx context.Context, w http.ResponseWr
 	})
 	l.Trace("received request to authenticate")
 
-	requestedAccountI := ctx.Value(util.APAccount)
-	if requestedAccountI == nil {
-		return ctx, false, errors.New("requested account not set in context")
+	if !util.IsInboxPath(r.URL) {
+		return nil, false, fmt.Errorf("path %s was not an inbox path", r.URL.String())
 	}
 
-	requestedAccount, ok := requestedAccountI.(*gtsmodel.Account)
-	if !ok || requestedAccount == nil {
-		return ctx, false, errors.New("requested account not parsebale from context")
+	username, err := util.ParseInboxPath(r.URL)
+	if err != nil {
+		return nil, false, fmt.Errorf("could not parse path %s: %s", r.URL.String(), err)
+	}
+
+	if username == "" {
+		return nil, false, errors.New("username was empty")
+	}
+
+	requestedAccount := &gtsmodel.Account{}
+	if err := f.db.GetLocalAccountByUsername(username, requestedAccount); err != nil {
+		return nil, false, fmt.Errorf("could not fetch requested account with username %s: %s", username, err)
 	}
 
 	publicKeyOwnerURI, err := f.AuthenticateFederatedRequest(requestedAccount.Username, r)
@@ -124,7 +133,6 @@ func (f *federator) AuthenticatePostInbox(ctx context.Context, w http.ResponseWr
 		}
 
 		// we don't know this account (yet) so let's dereference it right now
-		// TODO: slow-fed
 		person, err := f.DereferenceRemoteAccount(requestedAccount.Username, publicKeyOwnerURI)
 		if err != nil {
 			return ctx, false, fmt.Errorf("error dereferencing account with public key id %s: %s", publicKeyOwnerURI.String(), err)
@@ -138,7 +146,6 @@ func (f *federator) AuthenticatePostInbox(ctx context.Context, w http.ResponseWr
 	}
 
 	contextWithRequestingAccount := context.WithValue(ctx, util.APRequestingAccount, requestingAccount)
-
 	return contextWithRequestingAccount, true, nil
 }
 
@@ -180,9 +187,9 @@ func (f *federator) Blocked(ctx context.Context, actorIRIs []*url.URL) (bool, er
 //
 // Applications are not expected to handle every single ActivityStreams
 // type and extension. The unhandled ones are passed to DefaultCallback.
-func (f *federator) FederatingCallbacks(ctx context.Context) (pub.FederatingWrappedCallbacks, []interface{}, error) {
-	// TODO
-	return pub.FederatingWrappedCallbacks{}, nil, nil
+func (f *federator) FederatingCallbacks(ctx context.Context) (wrapped pub.FederatingWrappedCallbacks, other []interface{}, err error) {
+
+	return
 }
 
 // DefaultCallback is called for types that go-fed can deserialize but
@@ -207,7 +214,7 @@ func (f *federator) DefaultCallback(ctx context.Context, activity pub.Activity)
 // Zero or negative numbers indicate infinite recursion.
 func (f *federator) MaxInboxForwardingRecursionDepth(ctx context.Context) int {
 	// TODO
-	return 0
+	return 4
 }
 
 // MaxDeliveryRecursionDepth determines how deep to search within
@@ -217,7 +224,7 @@ func (f *federator) MaxInboxForwardingRecursionDepth(ctx context.Context) int {
 // Zero or negative numbers indicate infinite recursion.
 func (f *federator) MaxDeliveryRecursionDepth(ctx context.Context) int {
 	// TODO
-	return 0
+	return 4
 }
 
 // FilterForwarding allows the implementation to apply business logic
@@ -241,7 +248,7 @@ func (f *federator) FilterForwarding(ctx context.Context, potentialRecipients []
 // Always called, regardless whether the Federated Protocol or Social
 // API is enabled.
 func (f *federator) GetInbox(ctx context.Context, r *http.Request) (vocab.ActivityStreamsOrderedCollectionPage, error) {
-	// IMPLEMENTATION NOTE: For GoToSocial, we serve outboxes and inboxes through
+	// IMPLEMENTATION NOTE: For GoToSocial, we serve GETS to outboxes and inboxes through
 	// the CLIENT API, not through the federation API, so we just do nothing here.
 	return nil, nil
 }
diff --git a/internal/message/fediprocess.go b/internal/message/fediprocess.go
index dad1e848c..133e7dbaa 100644
--- a/internal/message/fediprocess.go
+++ b/internal/message/fediprocess.go
@@ -1,6 +1,7 @@
 package message
 
 import (
+	"context"
 	"fmt"
 	"net/http"
 
@@ -8,6 +9,7 @@ import (
 	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
 	"github.com/superseriousbusiness/gotosocial/internal/db"
 	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+	"github.com/superseriousbusiness/gotosocial/internal/util"
 )
 
 // authenticateAndDereferenceFediRequest authenticates the HTTP signature of an incoming federation request, using the given
@@ -130,3 +132,9 @@ func (p *processor) GetWebfingerAccount(requestedUsername string, request *http.
 		},
 	}, nil
 }
+
+func (p *processor) InboxPost(ctx context.Context, w http.ResponseWriter, r *http.Request) (bool, error) {
+	contextWithChannel := context.WithValue(ctx, util.APFromFederatorChanKey, p.fromFederator)
+	posted, err := p.federator.FederatingActor().PostInbox(contextWithChannel, w, r)
+	return posted, err
+}
diff --git a/internal/message/processor.go b/internal/message/processor.go
index c8d58a346..9d7f0c6c9 100644
--- a/internal/message/processor.go
+++ b/internal/message/processor.go
@@ -19,6 +19,7 @@
 package message
 
 import (
+	"context"
 	"net/http"
 
 	"github.com/sirupsen/logrus"
@@ -116,6 +117,18 @@ type Processor interface {
 
 	// GetWebfingerAccount handles the GET for a webfinger resource. Most commonly, it will be used for returning account lookups.
 	GetWebfingerAccount(requestedUsername string, request *http.Request) (*apimodel.WebfingerAccountResponse, ErrorWithCode)
+
+	// InboxPost handles POST requests to a user's inbox for new activitypub messages.
+	//
+	// InboxPost returns true if the request was handled as an ActivityPub POST to an actor's inbox.
+	// If false, the request was not an ActivityPub request and may still be handled by the caller in another way, such as serving a web page.
+	//
+	// If the error is nil, then the ResponseWriter's headers and response has already been written. If a non-nil error is returned, then no response has been written.
+	//
+	// If the Actor was constructed with the Federated Protocol enabled, side effects will occur.
+	//
+	// If the Federated Protocol is not enabled, writes the http.StatusMethodNotAllowed status code in the response. No side effects occur.
+	InboxPost(ctx context.Context, w http.ResponseWriter, r *http.Request) (bool, error)
 }
 
 // processor just implements the Processor interface
diff --git a/internal/transport/controller.go b/internal/transport/controller.go
index 2ee23f141..108f749cb 100644
--- a/internal/transport/controller.go
+++ b/internal/transport/controller.go
@@ -54,8 +54,8 @@ func NewController(config *config.Config, clock pub.Clock, client pub.HttpClient
 func (c *controller) NewTransport(pubKeyID string, privkey crypto.PrivateKey) (pub.Transport, error) {
 	prefs := []httpsig.Algorithm{httpsig.RSA_SHA256, httpsig.RSA_SHA512}
 	digestAlgo := httpsig.DigestSha256
-	getHeaders := []string{"(request-target)", "date", "accept"}
-	postHeaders := []string{"(request-target)", "date", "accept", "digest"}
+	getHeaders := []string{"(request-target)", "host", "date"}
+	postHeaders := []string{"(request-target)", "host", "date", "digest"}
 
 	getSigner, _, err := httpsig.NewSigner(prefs, digestAlgo, getHeaders, httpsig.Signature)
 	if err != nil {
diff --git a/internal/util/uri.go b/internal/util/uri.go
index 538df9210..2b0020b4e 100644
--- a/internal/util/uri.go
+++ b/internal/util/uri.go
@@ -61,6 +61,8 @@ const (
 	APRequestingAccount APContextKey = "requestingAccount"
 	// APRequestingPublicKeyID can be used to set and retrieve the public key ID of an incoming federation request.
 	APRequestingPublicKeyID APContextKey = "requestingPublicKeyID"
+	// APFromFederatorChanKey can be used to pass a pointer to the fromFederator channel into the federator for use in callbacks.
+	APFromFederatorChanKey APContextKey = "fromFederatorChan"
 )
 
 type ginContextKey struct{}