diff --git a/common/types/convert.go b/common/types/convert.go
index 24e01c273..137029a0e 100644
--- a/common/types/convert.go
+++ b/common/types/convert.go
@@ -14,6 +14,7 @@
 package types
 
 import (
+	"encoding/json"
 	"html/template"
 
 	"github.com/spf13/cast"
@@ -59,10 +60,20 @@ func TypeToString(v interface{}) (string, bool) {
 
 // ToString converts v to a string.
 func ToString(v interface{}) string {
+	s, _ := ToStringE(v)
+	return s
+}
+
+// ToStringE converts v to a string.
+func ToStringE(v interface{}) (string, error) {
 	if s, ok := TypeToString(v); ok {
-		return s
+		return s, nil
 	}
 
-	return cast.ToString(v)
-
+	switch s := v.(type) {
+	case json.RawMessage:
+		return string(s), nil
+	default:
+		return cast.ToStringE(v)
+	}
 }
diff --git a/common/types/convert_test.go b/common/types/convert_test.go
index 7f86f4c8a..8a4f04db2 100644
--- a/common/types/convert_test.go
+++ b/common/types/convert_test.go
@@ -14,6 +14,7 @@
 package types
 
 import (
+	"encoding/json"
 	"testing"
 
 	qt "github.com/frankban/quicktest"
@@ -27,3 +28,11 @@ func TestToStringSlicePreserveString(t *testing.T) {
 	c.Assert(ToStringSlicePreserveString(nil), qt.IsNil)
 
 }
+
+func TestToString(t *testing.T) {
+	c := qt.New(t)
+
+	c.Assert(ToString([]byte("Hugo")), qt.Equals, "Hugo")
+	c.Assert(ToString(json.RawMessage("Hugo")), qt.Equals, "Hugo")
+
+}
diff --git a/go.mod b/go.mod
index ad6ecda86..3969f67fc 100644
--- a/go.mod
+++ b/go.mod
@@ -18,6 +18,8 @@ require (
 	github.com/fortytw2/leaktest v1.3.0
 	github.com/frankban/quicktest v1.7.2
 	github.com/fsnotify/fsnotify v1.4.7
+	github.com/getkin/kin-openapi v0.14.0
+	github.com/ghodss/yaml v1.0.0
 	github.com/gobwas/glob v0.2.3
 	github.com/gohugoio/testmodBuilder/mods v0.0.0-20190520184928-c56af20f2e95
 	github.com/google/go-cmp v0.3.2-0.20191028172631-481baca67f93
@@ -65,7 +67,7 @@ require (
 	google.golang.org/genproto v0.0.0-20190522204451-c2c4e71fbf69 // indirect
 	gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 // indirect
 	gopkg.in/ini.v1 v1.51.1 // indirect
-	gopkg.in/yaml.v2 v2.2.7
+	gopkg.in/yaml.v2 v2.3.0
 )
 
 replace github.com/markbates/inflect => github.com/markbates/inflect v0.0.0-20171215194931-a12c3aec81a6
diff --git a/go.sum b/go.sum
index 98f010ece..7549b1822 100644
--- a/go.sum
+++ b/go.sum
@@ -127,6 +127,9 @@ github.com/frankban/quicktest v1.7.2 h1:2QxQoC1TS09S7fhCPsrvqYdvP1H5M1P1ih5ABm3B
 github.com/frankban/quicktest v1.7.2/go.mod h1:jaStnuzAqU1AJdCO0l53JDCJrVDKcS03DbaAcR7Ks/o=
 github.com/fsnotify/fsnotify v1.4.7 h1:IXs+QLmnXW2CcXuY+8Mzv/fWEsPGWxqefPtCP5CnV9I=
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
+github.com/getkin/kin-openapi v0.14.0 h1:hqwQL7kze/adt0wB+0UJR2nJm+gfUHqM0Gu4D8nByVc=
+github.com/getkin/kin-openapi v0.14.0/go.mod h1:WGRs2ZMM1Q8LR1QBEwUxC6RJEfaBcD0s+pcEVXFuAjw=
+github.com/ghodss/yaml v1.0.0 h1:wQHKEahhL6wmXdzwWG11gIVCkOv05bNOh+Rxn0yngAk=
 github.com/ghodss/yaml v1.0.0/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
 github.com/go-ini/ini v1.25.4/go.mod h1:ByCAeIL28uOIIG0E3PJtZPDL8WnHpFKFOtgjp+3Ies8=
 github.com/go-kit/kit v0.8.0/go.mod h1:xBxKIO96dXMWWy0MnWVtmwkA9/13aqxPnvrjFYMA2as=
@@ -352,6 +355,7 @@ github.com/stretchr/testify v1.2.2 h1:bSDNvY7ZPG5RlJ8otE/7V6gMiyenm9RtJ7IUVIAoJ1
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0Q=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
+github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
 github.com/subosito/gotenv v1.2.0 h1:Slr1R9HxAlEKefgq5jn9U+DnETlIUa6HfgEzj0g5d7s=
 github.com/subosito/gotenv v1.2.0/go.mod h1:N0PQaV/YGNqwC0u51sEeR/aUtSLEXKX9iv69rRypqCw=
 github.com/tdewolff/minify/v2 v2.6.1 h1:UJLhbs2Q/iDrqA79EEyKE48uYHeAMPVdiUzdtKsatJ8=
@@ -550,6 +554,8 @@ gopkg.in/yaml.v2 v2.2.4 h1:/eiJrUcujPVeJ3xlSWaiNi3uSVmDGBK1pDHUHAnao1I=
 gopkg.in/yaml.v2 v2.2.4/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.7 h1:VUgggvou5XRW9mHwD/yXxIYSMtY0zoKQf/v226p2nyo=
 gopkg.in/yaml.v2 v2.2.7/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v2 v2.3.0 h1:clyUAQHOM3G0M3f5vQj7LuJrETvjVot3Z5el9nffUtU=
+gopkg.in/yaml.v2 v2.3.0/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 honnef.co/go/tools v0.0.0-20180728063816-88497007e858/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=
 honnef.co/go/tools v0.0.0-20190102054323-c2f93a96b099/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=
 honnef.co/go/tools v0.0.0-20190106161140-3f1c8253044a/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=
diff --git a/hugolib/openapi_test.go b/hugolib/openapi_test.go
new file mode 100644
index 000000000..82f080311
--- /dev/null
+++ b/hugolib/openapi_test.go
@@ -0,0 +1,69 @@
+// Copyright 2019 The Hugo Authors. All rights reserved.
+//
+// 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 hugolib
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestOpenAPI3(t *testing.T) {
+	const openapi3Yaml = `openapi: 3.0.0
+info:
+  title: Sample API
+  description: Optional multiline or single-line description in [CommonMark](http://commonmark.org/help/) or HTML.
+  version: 0.1.9
+servers:
+  - url: http://api.example.com/v1
+    description: Optional server description, e.g. Main (production) server
+  - url: http://staging-api.example.com
+    description: Optional server description, e.g. Internal staging server for testing
+paths:
+  /users:
+    get:
+      summary: Returns a list of users.
+      description: Optional extended description in CommonMark or HTML.
+      responses:
+        '200':    # status code
+          description: A JSON array of user names
+          content:
+            application/json:
+              schema: 
+                type: array
+                items: 
+                  type: string
+`
+
+	b := newTestSitesBuilder(t).Running()
+	b.WithSourceFile("assets/api/myapi.yaml", openapi3Yaml)
+
+	b.WithTemplatesAdded("index.html", `
+{{ $api := resources.Get "api/myapi.yaml" | openapi3.Unmarshal }}
+
+API: {{ $api.Info.Title | safeHTML }}
+
+
+`)
+
+	b.Build(BuildCfg{})
+
+	b.AssertFileContent("public/index.html", `API: Sample API`)
+
+	b.EditFiles("assets/api/myapi.yaml", strings.Replace(openapi3Yaml, "Sample API", "Hugo API", -1))
+
+	b.Build(BuildCfg{})
+
+	b.AssertFileContent("public/index.html", `API: Hugo API`)
+
+}
diff --git a/parser/metadecoders/decoder.go b/parser/metadecoders/decoder.go
index 1a4a57076..2624ad16f 100644
--- a/parser/metadecoders/decoder.go
+++ b/parser/metadecoders/decoder.go
@@ -63,7 +63,7 @@ func (d Decoder) UnmarshalToMap(data []byte, f Format) (map[string]interface{},
 		return m, nil
 	}
 
-	err := d.unmarshal(data, f, &m)
+	err := d.UnmarshalTo(data, f, &m)
 
 	return m, err
 }
@@ -122,13 +122,13 @@ func (d Decoder) Unmarshal(data []byte, f Format) (interface{}, error) {
 
 	}
 	var v interface{}
-	err := d.unmarshal(data, f, &v)
+	err := d.UnmarshalTo(data, f, &v)
 
 	return v, err
 }
 
-// unmarshal unmarshals data in format f into v.
-func (d Decoder) unmarshal(data []byte, f Format, v interface{}) error {
+// UnmarshalTo unmarshals data in format f into v.
+func (d Decoder) UnmarshalTo(data []byte, f Format, v interface{}) error {
 
 	var err error
 
@@ -156,15 +156,17 @@ func (d Decoder) unmarshal(data []byte, f Format, v interface{}) error {
 		case *interface{}:
 			ptr = *v.(*interface{})
 		default:
-			return errors.Errorf("unknown type %T in YAML unmarshal", v)
+			// Not a map.
 		}
 
-		if mm, changed := stringifyMapKeys(ptr); changed {
-			switch v.(type) {
-			case *map[string]interface{}:
-				*v.(*map[string]interface{}) = mm.(map[string]interface{})
-			case *interface{}:
-				*v.(*interface{}) = mm
+		if ptr != nil {
+			if mm, changed := stringifyMapKeys(ptr); changed {
+				switch v.(type) {
+				case *map[string]interface{}:
+					*v.(*map[string]interface{}) = mm.(map[string]interface{})
+				case *interface{}:
+					*v.(*interface{}) = mm
+				}
 			}
 		}
 	case CSV:
diff --git a/resources/resource/resourcetypes.go b/resources/resource/resourcetypes.go
index 62431c06c..13ffc5ae3 100644
--- a/resources/resource/resourcetypes.go
+++ b/resources/resource/resourcetypes.go
@@ -173,6 +173,12 @@ type TranslationKeyProvider interface {
 	TranslationKey() string
 }
 
+// UnmarshableResource represents a Resource that can be unmarshaled to some other format.
+type UnmarshableResource interface {
+	ReadSeekCloserResource
+	Identifier
+}
+
 type resourceTypesHolder struct {
 	mediaType    media.Type
 	resourceType string
diff --git a/tpl/openapi/openapi3/init.go b/tpl/openapi/openapi3/init.go
new file mode 100644
index 000000000..1e1a4ae05
--- /dev/null
+++ b/tpl/openapi/openapi3/init.go
@@ -0,0 +1,42 @@
+// Copyright 2020 The Hugo Authors. All rights reserved.
+//
+// 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 openapi3
+
+import (
+	"github.com/gohugoio/hugo/deps"
+	"github.com/gohugoio/hugo/tpl/internal"
+)
+
+const name = "openapi3"
+
+func init() {
+	f := func(d *deps.Deps) *internal.TemplateFuncsNamespace {
+		ctx := New(d)
+
+		ns := &internal.TemplateFuncsNamespace{
+			Name:    name,
+			Context: func(args ...interface{}) interface{} { return ctx },
+		}
+
+		ns.AddMethodMapping(ctx.Unmarshal,
+			nil,
+			[][2]string{},
+		)
+
+		return ns
+
+	}
+
+	internal.AddTemplateFuncsNamespace(f)
+}
diff --git a/tpl/openapi/openapi3/openapi3.go b/tpl/openapi/openapi3/openapi3.go
new file mode 100644
index 000000000..7dfd2f6a7
--- /dev/null
+++ b/tpl/openapi/openapi3/openapi3.go
@@ -0,0 +1,97 @@
+// Copyright 2020 The Hugo Authors. All rights reserved.
+//
+// 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 openapi3
+
+import (
+	"io/ioutil"
+
+	gyaml "github.com/ghodss/yaml"
+
+	"github.com/pkg/errors"
+
+	kopenapi3 "github.com/getkin/kin-openapi/openapi3"
+	"github.com/gohugoio/hugo/cache/namedmemcache"
+	"github.com/gohugoio/hugo/deps"
+	"github.com/gohugoio/hugo/parser/metadecoders"
+	"github.com/gohugoio/hugo/resources/resource"
+)
+
+// New returns a new instance of the openapi3-namespaced template functions.
+func New(deps *deps.Deps) *Namespace {
+	// TODO1 consolidate when merging that "other branch" -- but be aware of the keys.
+	cache := namedmemcache.New()
+	deps.BuildStartListeners.Add(
+		func() {
+			cache.Clear()
+		})
+
+	return &Namespace{
+		cache: cache,
+		deps:  deps,
+	}
+}
+
+// Namespace provides template functions for the "openapi3".
+type Namespace struct {
+	cache *namedmemcache.Cache
+	deps  *deps.Deps
+}
+
+func (ns *Namespace) Unmarshal(r resource.UnmarshableResource) (*kopenapi3.Swagger, error) {
+
+	key := r.Key()
+	if key == "" {
+		return nil, errors.New("no Key set in Resource")
+	}
+
+	v, err := ns.cache.GetOrCreate(key, func() (interface{}, error) {
+		f := metadecoders.FormatFromMediaType(r.MediaType())
+		if f == "" {
+			return nil, errors.Errorf("MIME %q not supported", r.MediaType())
+		}
+
+		reader, err := r.ReadSeekCloser()
+		if err != nil {
+			return nil, err
+		}
+		defer reader.Close()
+
+		b, err := ioutil.ReadAll(reader)
+		if err != nil {
+			return nil, err
+		}
+
+		s := &kopenapi3.Swagger{}
+		switch f {
+		case metadecoders.YAML:
+			err = gyaml.Unmarshal(b, s)
+		default:
+			err = metadecoders.Default.UnmarshalTo(b, f, s)
+		}
+		if err != nil {
+			return nil, err
+		}
+
+		err = kopenapi3.NewSwaggerLoader().ResolveRefsIn(s, nil)
+
+		return s, err
+	})
+
+	if err != nil {
+		return nil, err
+	}
+
+	return v.(*kopenapi3.Swagger), nil
+
+}
diff --git a/tpl/tplimpl/template_funcs.go b/tpl/tplimpl/template_funcs.go
index ccf33d8ba..9141de3f1 100644
--- a/tpl/tplimpl/template_funcs.go
+++ b/tpl/tplimpl/template_funcs.go
@@ -44,6 +44,7 @@ import (
 	_ "github.com/gohugoio/hugo/tpl/inflect"
 	_ "github.com/gohugoio/hugo/tpl/lang"
 	_ "github.com/gohugoio/hugo/tpl/math"
+	_ "github.com/gohugoio/hugo/tpl/openapi/openapi3"
 	_ "github.com/gohugoio/hugo/tpl/os"
 	_ "github.com/gohugoio/hugo/tpl/partials"
 	_ "github.com/gohugoio/hugo/tpl/path"
diff --git a/tpl/transform/unmarshal.go b/tpl/transform/unmarshal.go
index da06b6aa1..b606c870a 100644
--- a/tpl/transform/unmarshal.go
+++ b/tpl/transform/unmarshal.go
@@ -17,17 +17,20 @@ import (
 	"io/ioutil"
 	"strings"
 
+	"github.com/gohugoio/hugo/resources/resource"
+
+	"github.com/gohugoio/hugo/common/types"
+
 	"github.com/mitchellh/mapstructure"
 
 	"github.com/gohugoio/hugo/helpers"
 	"github.com/gohugoio/hugo/parser/metadecoders"
-	"github.com/gohugoio/hugo/resources/resource"
 	"github.com/pkg/errors"
 
 	"github.com/spf13/cast"
 )
 
-// Unmarshal unmarshals the data given, which can be either a string
+// Unmarshal unmarshals the data given, which can be either a string, json.RawMessage
 // or a Resource. Supported formats are JSON, TOML, YAML, and CSV.
 // You can optionally provide an options map as the first argument.
 func (ns *Namespace) Unmarshal(args ...interface{}) (interface{}, error) {
@@ -55,7 +58,7 @@ func (ns *Namespace) Unmarshal(args ...interface{}) (interface{}, error) {
 		}
 	}
 
-	if r, ok := data.(unmarshableResource); ok {
+	if r, ok := data.(resource.UnmarshableResource); ok {
 		key := r.Key()
 
 		if key == "" {
@@ -87,7 +90,7 @@ func (ns *Namespace) Unmarshal(args ...interface{}) (interface{}, error) {
 		})
 	}
 
-	dataStr, err := cast.ToStringE(data)
+	dataStr, err := types.ToStringE(data)
 	if err != nil {
 		return nil, errors.Errorf("type %T not supported", data)
 	}
@@ -104,12 +107,6 @@ func (ns *Namespace) Unmarshal(args ...interface{}) (interface{}, error) {
 	})
 }
 
-// All the relevant resources implements this interface.
-type unmarshableResource interface {
-	resource.ReadSeekCloserResource
-	resource.Identifier
-}
-
 func decodeDecoder(m map[string]interface{}) (metadecoders.Decoder, error) {
 	opts := metadecoders.Default
 
diff --git a/tpl/transform/unmarshal_test.go b/tpl/transform/unmarshal_test.go
index 7b0caa07f..183bdefd5 100644
--- a/tpl/transform/unmarshal_test.go
+++ b/tpl/transform/unmarshal_test.go
@@ -20,11 +20,11 @@ import (
 	"testing"
 
 	"github.com/gohugoio/hugo/common/hugio"
+	"github.com/gohugoio/hugo/resources/resource"
 
 	"github.com/gohugoio/hugo/media"
 
 	qt "github.com/frankban/quicktest"
-	"github.com/gohugoio/hugo/resources/resource"
 	"github.com/spf13/viper"
 )