diff --git a/lockfile.go b/lockfile.go
new file mode 100644
index 0000000..6d28666
--- /dev/null
+++ b/lockfile.go
@@ -0,0 +1,13 @@
+package feynman
+
+type CargoLock struct {
+	Packages []LockPackage `toml:"package"`
+}
+
+type LockPackage struct {
+	Name         string   `toml:"name"`
+	Version      string   `toml:"version"`
+	Dependencies []string `toml:"dependencies"`
+	Source       string   `toml:"source"`
+	Checksum     string   `toml:"checksum"`
+}
diff --git a/manifest.go b/manifest.go
new file mode 100644
index 0000000..bb59c42
--- /dev/null
+++ b/manifest.go
@@ -0,0 +1,51 @@
+package feynman
+
+type CargoManifest struct {
+	Package           `toml:"package"`
+	Library           Target                `toml:"lib"`
+	Binaries          []Target              `toml:"bin"`
+	Tests             []Target              `toml:"test"`
+	Dependencies      map[string]Dependency `toml:"dependencies"`
+	BuildDependencies map[string]Dependency `toml:"build-dependencies"`
+	DevDependencies   map[string]Dependency `toml:"dev-dependencies"`
+	Target            TargetTable           `toml:"target"`
+}
+type Package struct {
+	Name        string `toml:"name"`
+	Version     string `toml:"version"`
+	Edition     string `toml:"edition"`
+	RustVersion string `toml:"rust-version"`
+	Workspace   string `toml:"workspace"`
+	Build       string `toml:"build"`
+	Links       string `toml:"links"`
+	Autolib     bool   `toml:"autolib"`
+	Autobins    bool   `toml:"autobins"`
+	Autotests   bool   `toml:"autotests"`
+	Resolver    string `toml:"resolver"`
+}
+
+type Target struct {
+	Name             string   `toml:"name"`
+	Path             string   `toml:"path"`
+	Test             bool     `toml:"test"`
+	ProcMacro        bool     `toml:"proc-macro"`
+	Harness          bool     `toml:"harness"`
+	CrateType        []string `toml:"crate-type"`
+	RequiredFeatures []string `toml:"required-features"`
+}
+
+// n.b. only crates.io and local dependencies are supported.
+type Dependency struct {
+	Version         string   `toml:"version"`
+	Path            string   `toml:"path"`
+	DefaultFeatures bool     `toml:"default-features"`
+	Features        []string `toml:"features"`
+	Optional        bool     `toml:"optional"`
+	Package         string   `toml:"package"`
+	Workspace       string   `toml:"workspace"`
+}
+
+type DependenciesTable struct {
+	Dependencies map[string]Dependency `toml:"dependencies"`
+}
+type TargetTable map[string]DependenciesTable