diff --git a/cmd/new.go b/cmd/new.go
index 313176c..af6f147 100644
--- a/cmd/new.go
+++ b/cmd/new.go
@@ -1,11 +1,17 @@
 package cmd
 
-import "github.com/mickael-menu/zk/core/zk"
+import (
+	"fmt"
+
+	"github.com/mickael-menu/zk/core/zk"
+)
 
 type New struct {
 	Directory string `arg optional name:"directory" default:"."`
 }
 
 func (cmd *New) Run() error {
-	return zk.Open(cmd.Directory)
+	zk, err := zk.Open(cmd.Directory)
+	fmt.Printf("%+v\n", zk)
+	return err
 }
diff --git a/core/zk/config.go b/core/zk/config.go
new file mode 100644
index 0000000..f680c61
--- /dev/null
+++ b/core/zk/config.go
@@ -0,0 +1,49 @@
+package zk
+
+import (
+	"github.com/google/go-cmp/cmp"
+	"github.com/hashicorp/hcl/v2/hclsimple"
+	"github.com/mickael-menu/zk/util/errors"
+)
+
+// Config holds the user configuration of a slip box.
+type Config struct {
+	root rootConfig
+}
+
+func (c1 Config) Equal(c2 Config) bool {
+	return cmp.Equal(c1.root, c2.root)
+}
+
+type rootConfig struct {
+	Editor    string            `hcl:"editor,optional"`
+	Extension string            `hcl:"extension,optional"`
+	Filename  string            `hcl:"filename,optional"`
+	Template  string            `hcl:"template,optional"`
+	RandomID  *randomIDConfig   `hcl:"random_id,block"`
+	Dirs      []dirConfig       `hcl:"dir,block"`
+	Ext       map[string]string `hcl:"ext,optional"`
+}
+
+type randomIDConfig struct {
+	Charset string `hcl:"charset,optional"`
+	Length  int    `hcl:"length,optional"`
+	Case    string `hcl:"case,optional"`
+}
+
+type dirConfig struct {
+	Dir      string            `hcl:"dir,label"`
+	Filename string            `hcl:"filename,optional"`
+	Template string            `hcl:"template,optional"`
+	Ext      map[string]string `hcl:"ext,optional"`
+}
+
+// parseConfig creates a new Config instance from its HCL representation.
+func parseConfig(content []byte) (*Config, error) {
+	var root rootConfig
+	err := hclsimple.Decode(".zk/config.hcl", content, nil, &root)
+	if err != nil {
+		return nil, errors.Wrap(err, "failed to read config")
+	}
+	return &Config{root}, nil
+}
diff --git a/core/zk/config_test.go b/core/zk/config_test.go
new file mode 100644
index 0000000..81806a4
--- /dev/null
+++ b/core/zk/config_test.go
@@ -0,0 +1,75 @@
+package zk
+
+import (
+	"testing"
+
+	"github.com/mickael-menu/zk/util/assert"
+)
+
+// Parse a minimal configuration file.
+func TestParseMinimal(t *testing.T) {
+	config, err := parseConfig([]byte(""))
+
+	assert.Nil(t, err)
+	assert.Equal(t, config, &Config{rootConfig{}})
+}
+
+// Parse a complete configuration file.
+func TestParseComplete(t *testing.T) {
+	config, err := parseConfig([]byte(`
+		// Comment
+		editor = "vim"
+		extension = "note"
+		filename = "{{random-id}}.note"
+		template = "default.note"
+		random_id {
+			charset = "alphanum"
+			length = 4
+			case = "lower"
+		}
+		ext = {
+			hello = "world"
+			salut = "le monde"
+		}
+		dir "log" {
+			filename = "{{date}}.md"
+			template = "log.md"
+			ext = {
+				log-ext = "value"
+			}
+		}
+	`))
+
+	assert.Nil(t, err)
+	assert.Equal(t, config, &Config{rootConfig{
+		Editor:    "vim",
+		Extension: "note",
+		Filename:  "{{random-id}}.note",
+		Template:  "default.note",
+		RandomID: &randomIDConfig{
+			Charset: "alphanum",
+			Length:  4,
+			Case:    "lower",
+		},
+		Dirs: []dirConfig{
+			dirConfig{
+				Dir:      "log",
+				Filename: "{{date}}.md",
+				Template: "log.md",
+				Ext:      map[string]string{"log-ext": "value"},
+			},
+		},
+		Ext: map[string]string{
+			"hello": "world",
+			"salut": "le monde",
+		},
+	}})
+}
+
+// Parsing failure
+func TestParseInvalidConfig(t *testing.T) {
+	config, err := parseConfig([]byte("unknown = 'value'"))
+
+	assert.NotNil(t, err)
+	assert.Nil(t, config)
+}
diff --git a/core/zk/zk.go b/core/zk/zk.go
index 7cd687e..8b212a0 100644
--- a/core/zk/zk.go
+++ b/core/zk/zk.go
@@ -2,27 +2,47 @@ package zk
 
 import (
 	"fmt"
+	"io/ioutil"
 	"os"
 	"path/filepath"
 
 	"github.com/mickael-menu/zk/util/errors"
 )
 
-const defaultConfig = `
-# Test
-test = thing
+const defaultConfig = `editor = "nvim"
+dir "log" {
+	template = "log.md"
+}
 `
 
+type Zk struct {
+	Config Config
+}
+
 // Open locates a slip box at the given path and parses its configuration.
-func Open(path string) error {
+func Open(path string) (*Zk, error) {
 	wrap := errors.Wrapper("open failed")
 
 	path, err := filepath.Abs(path)
 	if err != nil {
-		return wrap(err)
+		return nil, wrap(err)
 	}
-	_, err = locateRoot(path)
-	return wrap(err)
+	path, err = locateRoot(path)
+	if err != nil {
+		return nil, wrap(err)
+	}
+
+	configContent, err := ioutil.ReadFile(filepath.Join(path, ".zk/config.hcl"))
+	if err != nil {
+		return nil, wrap(err)
+	}
+
+	config, err := parseConfig(configContent)
+	if err != nil {
+		return nil, wrap(err)
+	}
+
+	return &Zk{*config}, nil
 }
 
 // Create initializes a new slip box at the given path.
@@ -45,7 +65,7 @@ func Create(path string) error {
 	}
 
 	// Write default config.toml.
-	f, err := os.Create(filepath.Join(path, ".zk/config.toml"))
+	f, err := os.Create(filepath.Join(path, ".zk/config.hcl"))
 	if err != nil {
 		return wrap(err)
 	}
diff --git a/go.mod b/go.mod
index 710254c..dcf1a2e 100644
--- a/go.mod
+++ b/go.mod
@@ -2,4 +2,8 @@ module github.com/mickael-menu/zk
 
 go 1.15
 
-require github.com/alecthomas/kong v0.2.12
+require (
+	github.com/alecthomas/kong v0.2.12
+	github.com/google/go-cmp v0.3.1
+	github.com/hashicorp/hcl/v2 v2.8.1
+)
diff --git a/go.sum b/go.sum
index 8102a3a..30a9b7a 100644
--- a/go.sum
+++ b/go.sum
@@ -1,7 +1,46 @@
+github.com/agext/levenshtein v1.2.1 h1:QmvMAjj2aEICytGiWzmxoE0x2KZvE0fvmqMOfy2tjT8=
+github.com/agext/levenshtein v1.2.1/go.mod h1:JEDfjyjHDjOF/1e4FlBE/PkbqA9OfWu2ki2W0IB5558=
 github.com/alecthomas/kong v0.2.12 h1:X3kkCOXGUNzLmiu+nQtoxWqj4U2a39MpSJR3QdQXOwI=
 github.com/alecthomas/kong v0.2.12/go.mod h1:kQOmtJgV+Lb4aj+I2LEn40cbtawdWJ9Y8QLq+lElKxE=
+github.com/apparentlymart/go-dump v0.0.0-20180507223929-23540a00eaa3/go.mod h1:oL81AME2rN47vu18xqj1S1jPIPuN7afo62yKTNn3XMM=
+github.com/apparentlymart/go-textseg v1.0.0 h1:rRmlIsPEEhUTIKQb7T++Nz/A5Q6C9IuX2wFoYVvnCs0=
+github.com/apparentlymart/go-textseg v1.0.0/go.mod h1:z96Txxhf3xSFMPmb5X/1W05FF/Nj9VFpLOpjS5yuumk=
+github.com/apparentlymart/go-textseg/v12 v12.0.0 h1:bNEQyAGak9tojivJNkoqWErVCQbjdL7GzRt3F8NvfJ0=
+github.com/apparentlymart/go-textseg/v12 v12.0.0/go.mod h1:S/4uRK2UtaQttw1GenVJEynmyUenKwP++x/+DdGV/Ec=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/go-test/deep v1.0.3/go.mod h1:wGDj63lr65AM2AQyKZd/NYHGb0R+1RLqB8NKt3aSFNA=
+github.com/golang/protobuf v1.1.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/google/go-cmp v0.3.1 h1:Xye71clBPdm5HgqGwUkwhbynsUJZhDbS20FvLhQ2izg=
+github.com/google/go-cmp v0.3.1/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
+github.com/hashicorp/hcl v1.0.0 h1:0Anlzjpi4vEasTeNFn2mLJgTSwt0+6sfsiTG8qcWGx4=
+github.com/hashicorp/hcl/v2 v2.8.1 h1:FJ60CIYaMyJOKzPndhMyjiz353Fd+2jr6PodF5Xzb08=
+github.com/hashicorp/hcl/v2 v2.8.1/go.mod h1:bQTN5mpo+jewjJgh8jr0JUguIi7qPHUF6yIfAEN3jqY=
+github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
+github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
+github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
+github.com/kylelemons/godebug v0.0.0-20170820004349-d65d576e9348/go.mod h1:B69LEHPfb2qLo0BaaOLcbitczOKLWTsrBG9LczfCD4k=
+github.com/mitchellh/go-wordwrap v0.0.0-20150314170334-ad45545899c7 h1:DpOJ2HYzCv8LZP15IdmG+YdwD2luVPHITV96TkirNBM=
+github.com/mitchellh/go-wordwrap v0.0.0-20150314170334-ad45545899c7/go.mod h1:ZXFpozHsX6DPmq2I0TCekCxypsnAUbP2oI0UX1GXzOo=
 github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/sergi/go-diff v1.0.0/go.mod h1:0CfEIISq7TuYL3j771MWULgwwjU+GofnZX9QAmXWZgo=
+github.com/spf13/pflag v1.0.2/go.mod h1:DYY7MBk1bdzusC3SYhjObp+wFpr4gzcvqqNjLnInEg4=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
+github.com/vmihailenco/msgpack v3.3.3+incompatible/go.mod h1:fy3FlTQTDXWkZ7Bh6AcGMlsjHatGryHQYUTf1ShIgkk=
+github.com/zclconf/go-cty v1.2.0 h1:sPHsy7ADcIZQP3vILvTjrh74ZA175TFP5vqiNK1UmlI=
+github.com/zclconf/go-cty v1.2.0/go.mod h1:hOPWgoHbaTUnI5k4D2ld+GRpFJSCe6bCM7m1q/N4PQ8=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20190426145343-a29dc8fdc734/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
+golang.org/x/net v0.0.0-20180811021610-c39426892332/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20190502175342-a43fa875dd82/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/text v0.3.2 h1:tW2bmiBqwgJj/UpqtC8EpXEZVYOwU0yG4iWbprSVAcs=
+golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
+gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
diff --git a/util/assert/assert.go b/util/assert/assert.go
new file mode 100644
index 0000000..c19ad83
--- /dev/null
+++ b/util/assert/assert.go
@@ -0,0 +1,31 @@
+package assert
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+)
+
+func Nil(t *testing.T, value interface{}) {
+	if !isNil(value) {
+		t.Errorf("Expected %v (type %v) to be nil", value, reflect.TypeOf(value))
+	}
+}
+
+func NotNil(t *testing.T, value interface{}) {
+	if isNil(value) {
+		t.Errorf("Expected %v (type %v) to not be nil", value, reflect.TypeOf(value))
+	}
+}
+
+func isNil(value interface{}) bool {
+	return value == nil ||
+		(reflect.ValueOf(value).Kind() == reflect.Ptr && reflect.ValueOf(value).IsNil())
+}
+
+func Equal(t *testing.T, value interface{}, expected interface{}) {
+	if !cmp.Equal(value, expected) {
+		t.Errorf("Received %+v (type %v), expected %+v (type %v)", value, reflect.TypeOf(value), expected, reflect.TypeOf(expected))
+	}
+}