diff --git a/lib/Cargo.toml b/lib/Cargo.toml
index 485ed108..e2bb3f1f 100644
--- a/lib/Cargo.toml
+++ b/lib/Cargo.toml
@@ -15,6 +15,10 @@ edition = "2018"
 [package.metadata.docs.rs]
 all-features = true
 
+[features]
+default = []
+sophia = ["sophia_api"]
+
 [dependencies]
 rocksdb = { version = "0.14", optional = true }
 sled = { version = "0.34", optional = true }
@@ -35,6 +39,7 @@ nom = "5"
 peg = "0.6"
 siphasher = "0.3"
 lasso = {version="0.3", features=["multi-threaded"]}
+sophia_api = { version = "0.6.2", optional = true }
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]
 js-sys = "0.3"
@@ -43,6 +48,7 @@ getrandom = {version="0.1", features=["wasm-bindgen"]}
 [dev-dependencies]
 rayon = "1"
 criterion = "0.3"
+sophia_api = { version = "0.6.2", features = ["test_macro"] }
 
 [target.'cfg(target_arch = "wasm32")'.dev-dependencies]
 wasm-bindgen-test = "0.3"
diff --git a/lib/src/lib.rs b/lib/src/lib.rs
index ba7c43f1..33835e50 100644
--- a/lib/src/lib.rs
+++ b/lib/src/lib.rs
@@ -118,3 +118,13 @@ pub use crate::store::memory::MemoryStore;
 pub use crate::store::rocksdb::RocksDbStore;
 #[cfg(feature = "sled")]
 pub use crate::store::sled::SledStore;
+
+#[cfg(feature = "sophia")]
+/// Provides implementation of [Sophia] traits for Oxigraph types,
+/// if the `sophia` feature is enabled.
+///
+/// [Sophia]: https://docs.rs/sophia/latest/sophia/
+mod sophia {
+    mod model;
+    mod store;
+}
diff --git a/lib/src/sophia/model.rs b/lib/src/sophia/model.rs
new file mode 100644
index 00000000..69bfdf5c
--- /dev/null
+++ b/lib/src/sophia/model.rs
@@ -0,0 +1,408 @@
+//! This crate provides implementation of [Sophia] traits for the `model` module.
+//! [Sophia]: https://docs.rs/sophia/latest/sophia/
+
+use crate::model::*;
+use sophia_api::term::*;
+use std::fmt;
+
+impl TTerm for BlankNode {
+    fn kind(&self) -> TermKind {
+        TermKind::BlankNode
+    }
+
+    fn value_raw(&self) -> RawValue<'_> {
+        self.as_str().into()
+    }
+
+    fn as_dyn(&self) -> &dyn TTerm {
+        self
+    }
+}
+
+impl TryCopyTerm for BlankNode {
+    type Error = SophiaToOxigraphConversionError;
+
+    fn try_copy<T>(other: &T) -> Result<Self, Self::Error>
+    where
+        T: TTerm + ?Sized,
+    {
+        match other.kind() {
+            TermKind::BlankNode => Ok(BlankNode::new_unchecked(other.value_raw().0)),
+            _ => Err(SophiaToOxigraphConversionError),
+        }
+    }
+}
+
+impl<'a> TTerm for BlankNodeRef<'a> {
+    fn kind(&self) -> TermKind {
+        TermKind::BlankNode
+    }
+
+    fn value_raw(&self) -> RawValue<'_> {
+        self.as_str().into()
+    }
+
+    fn as_dyn(&self) -> &dyn TTerm {
+        self
+    }
+}
+
+impl TTerm for Literal {
+    fn kind(&self) -> TermKind {
+        TermKind::Literal
+    }
+
+    fn value_raw(&self) -> RawValue<'_> {
+        Literal::value(self).into()
+    }
+
+    fn datatype(&self) -> Option<SimpleIri<'_>> {
+        Some(SimpleIri::new_unchecked(
+            Literal::datatype(self).as_str(),
+            None,
+        ))
+    }
+
+    fn language(&self) -> Option<&str> {
+        Literal::language(self)
+    }
+
+    fn as_dyn(&self) -> &dyn TTerm {
+        self
+    }
+}
+
+impl TryCopyTerm for Literal {
+    type Error = SophiaToOxigraphConversionError;
+
+    fn try_copy<T>(other: &T) -> Result<Self, Self::Error>
+    where
+        T: TTerm + ?Sized,
+    {
+        match other.kind() {
+            TermKind::Literal => match other.language() {
+                Some(tag) => Ok(Literal::new_language_tagged_literal_unchecked(
+                    other.value_raw().0,
+                    tag,
+                )),
+                None => Ok(Literal::new_typed_literal(
+                    other.value_raw().0,
+                    other.datatype().unwrap(),
+                )),
+            },
+            _ => Err(SophiaToOxigraphConversionError),
+        }
+    }
+}
+
+impl<'a> TTerm for LiteralRef<'a> {
+    fn kind(&self) -> TermKind {
+        TermKind::Literal
+    }
+
+    fn value_raw(&self) -> RawValue<'_> {
+        LiteralRef::value(*self).into()
+    }
+
+    fn datatype(&self) -> Option<SimpleIri<'_>> {
+        Some(SimpleIri::new_unchecked(
+            LiteralRef::datatype(*self).as_str(),
+            None,
+        ))
+    }
+
+    fn language(&self) -> Option<&str> {
+        LiteralRef::language(*self)
+    }
+
+    fn as_dyn(&self) -> &dyn TTerm {
+        self
+    }
+}
+
+impl TTerm for NamedNode {
+    fn kind(&self) -> TermKind {
+        TermKind::Iri
+    }
+
+    fn value_raw(&self) -> RawValue<'_> {
+        self.as_str().into()
+    }
+
+    fn as_dyn(&self) -> &dyn TTerm {
+        self
+    }
+}
+
+impl TryCopyTerm for NamedNode {
+    type Error = SophiaToOxigraphConversionError;
+
+    fn try_copy<T>(other: &T) -> Result<Self, Self::Error>
+    where
+        T: TTerm + ?Sized,
+    {
+        match other.kind() {
+            TermKind::Iri => Ok(NamedNode::new_unchecked(other.value())),
+            _ => Err(SophiaToOxigraphConversionError),
+        }
+    }
+}
+
+impl<'a> From<SimpleIri<'a>> for NamedNode {
+    fn from(other: SimpleIri<'a>) -> Self {
+        NamedNode::new_unchecked(other.value())
+    }
+}
+
+impl<'a> TTerm for NamedNodeRef<'a> {
+    fn kind(&self) -> TermKind {
+        TermKind::BlankNode
+    }
+
+    fn value_raw(&self) -> RawValue<'_> {
+        self.as_str().into()
+    }
+
+    fn as_dyn(&self) -> &dyn TTerm {
+        self
+    }
+}
+
+impl From<GraphName> for Option<Term> {
+    fn from(other: GraphName) -> Self {
+        use GraphName::*;
+        match other {
+            NamedNode(n) => Some(n.into()),
+            BlankNode(n) => Some(n.into()),
+            DefaultGraph => None,
+        }
+    }
+}
+
+impl<'a> From<GraphNameRef<'a>> for Option<TermRef<'a>> {
+    fn from(other: GraphNameRef<'a>) -> Self {
+        use GraphNameRef::*;
+        match other {
+            NamedNode(n) => Some(n.into()),
+            BlankNode(n) => Some(n.into()),
+            DefaultGraph => None,
+        }
+    }
+}
+
+impl TTerm for NamedOrBlankNode {
+    fn kind(&self) -> TermKind {
+        use NamedOrBlankNode::*;
+        match self {
+            NamedNode(_) => TermKind::Iri,
+            BlankNode(_) => TermKind::BlankNode,
+        }
+    }
+
+    fn value_raw(&self) -> RawValue<'_> {
+        use NamedOrBlankNode::*;
+        match self {
+            NamedNode(n) => n.value_raw(),
+            BlankNode(n) => n.value_raw(),
+        }
+    }
+
+    fn as_dyn(&self) -> &dyn TTerm {
+        use NamedOrBlankNode::*;
+        match self {
+            NamedNode(n) => n.as_dyn(),
+            BlankNode(n) => n.as_dyn(),
+        }
+    }
+}
+
+impl TryCopyTerm for NamedOrBlankNode {
+    type Error = SophiaToOxigraphConversionError;
+
+    fn try_copy<T>(other: &T) -> Result<Self, Self::Error>
+    where
+        T: TTerm + ?Sized,
+    {
+        match other.kind() {
+            TermKind::Iri => Ok(NamedNode::try_copy(other).unwrap().into()),
+            TermKind::BlankNode => Ok(BlankNode::try_copy(other).unwrap().into()),
+            _ => Err(SophiaToOxigraphConversionError),
+        }
+    }
+}
+
+impl<'a> TTerm for NamedOrBlankNodeRef<'a> {
+    fn kind(&self) -> TermKind {
+        use NamedOrBlankNodeRef::*;
+        match self {
+            NamedNode(_) => TermKind::Iri,
+            BlankNode(_) => TermKind::BlankNode,
+        }
+    }
+
+    fn value_raw(&self) -> RawValue<'_> {
+        use NamedOrBlankNodeRef::*;
+        match self {
+            NamedNode(n) => n.value_raw(),
+            BlankNode(n) => n.value_raw(),
+        }
+    }
+
+    fn as_dyn(&self) -> &dyn TTerm {
+        use NamedOrBlankNodeRef::*;
+        match self {
+            NamedNode(n) => n.as_dyn(),
+            BlankNode(n) => n.as_dyn(),
+        }
+    }
+}
+
+impl TTerm for Term {
+    fn kind(&self) -> TermKind {
+        use Term::*;
+        match self {
+            NamedNode(_) => TermKind::Iri,
+            BlankNode(_) => TermKind::BlankNode,
+            Literal(_) => TermKind::Literal,
+        }
+    }
+
+    fn value_raw(&self) -> RawValue<'_> {
+        use Term::*;
+        match self {
+            NamedNode(n) => n.value_raw(),
+            BlankNode(n) => n.value_raw(),
+            Literal(l) => l.value_raw(),
+        }
+    }
+
+    fn datatype(&self) -> Option<SimpleIri<'_>> {
+        use Term::*;
+        match self {
+            Literal(l) => TTerm::datatype(l),
+            _ => None,
+        }
+    }
+
+    fn language(&self) -> Option<&str> {
+        use Term::*;
+        match self {
+            Literal(l) => TTerm::language(l),
+            _ => None,
+        }
+    }
+
+    fn as_dyn(&self) -> &dyn TTerm {
+        use Term::*;
+        match self {
+            NamedNode(n) => n.as_dyn(),
+            BlankNode(n) => n.as_dyn(),
+            Literal(l) => l.as_dyn(),
+        }
+    }
+}
+
+impl TryCopyTerm for Term {
+    type Error = SophiaToOxigraphConversionError;
+
+    fn try_copy<T>(other: &T) -> Result<Self, Self::Error>
+    where
+        T: TTerm + ?Sized,
+    {
+        match other.kind() {
+            TermKind::Iri => Ok(NamedNode::try_copy(other).unwrap().into()),
+            TermKind::BlankNode => Ok(BlankNode::try_copy(other).unwrap().into()),
+            TermKind::Literal => Ok(Literal::try_copy(other).unwrap().into()),
+            _ => Err(SophiaToOxigraphConversionError),
+        }
+    }
+}
+
+impl<'a> TTerm for TermRef<'a> {
+    fn kind(&self) -> TermKind {
+        use TermRef::*;
+        match self {
+            NamedNode(_) => TermKind::Iri,
+            BlankNode(_) => TermKind::BlankNode,
+            Literal(_) => TermKind::Literal,
+        }
+    }
+
+    fn value_raw(&self) -> RawValue<'_> {
+        use TermRef::*;
+        match self {
+            NamedNode(n) => n.value_raw(),
+            BlankNode(n) => n.value_raw(),
+            Literal(l) => l.value_raw(),
+        }
+    }
+
+    fn datatype(&self) -> Option<SimpleIri<'_>> {
+        use TermRef::*;
+        match self {
+            Literal(l) => TTerm::datatype(l),
+            _ => None,
+        }
+    }
+
+    fn language(&self) -> Option<&str> {
+        use TermRef::*;
+        match self {
+            Literal(l) => TTerm::language(l),
+            _ => None,
+        }
+    }
+
+    fn as_dyn(&self) -> &dyn TTerm {
+        use TermRef::*;
+        match self {
+            NamedNode(n) => n.as_dyn(),
+            BlankNode(n) => n.as_dyn(),
+            Literal(l) => l.as_dyn(),
+        }
+    }
+}
+
+impl From<Quad> for ([Term; 3], Option<Term>) {
+    fn from(other: Quad) -> Self {
+        (
+            [other.subject.into(), other.predicate.into(), other.object],
+            other.graph_name.into(),
+        )
+    }
+}
+
+impl<'a> From<QuadRef<'a>> for ([TermRef<'a>; 3], Option<TermRef<'a>>) {
+    fn from(other: QuadRef<'a>) -> Self {
+        (
+            [other.subject.into(), other.predicate.into(), other.object],
+            other.graph_name.into(),
+        )
+    }
+}
+
+impl From<Triple> for [Term; 3] {
+    fn from(other: Triple) -> Self {
+        [other.subject.into(), other.predicate.into(), other.object]
+    }
+}
+
+impl<'a> From<TripleRef<'a>> for [TermRef<'a>; 3] {
+    fn from(other: TripleRef<'a>) -> Self {
+        [other.subject.into(), other.predicate.into(), other.object]
+    }
+}
+
+/// Error raised when trying to conpy a [Sophia]
+/// term as an incompatible Oxigraph term
+/// (e.g. a literal into `NamedNode`).
+///
+/// [Sophia]: https://docs.rs/sophia/latest/sophia/
+#[derive(Clone, Copy, Debug)]
+pub struct SophiaToOxigraphConversionError;
+impl fmt::Display for SophiaToOxigraphConversionError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{:?}", self)
+    }
+}
+impl std::error::Error for SophiaToOxigraphConversionError {}
diff --git a/lib/src/sophia/store.rs b/lib/src/sophia/store.rs
new file mode 100644
index 00000000..e23e86f4
--- /dev/null
+++ b/lib/src/sophia/store.rs
@@ -0,0 +1,806 @@
+//! This crate provides implementation of [Sophia] traits for the `store` module.
+//! [Sophia]: https://docs.rs/sophia/latest/sophia/
+use crate::model::*;
+use crate::sparql::{EvaluationError, QueryOptions, QueryResults};
+use crate::store::*;
+use sophia_api::dataset::*;
+use sophia_api::quad::stream::{QuadSource, StreamResult};
+use sophia_api::quad::streaming_mode::{ByValue, StreamedQuad};
+use sophia_api::term::{TTerm, TermKind, TryCopyTerm};
+use std::collections::HashSet;
+use std::convert::Infallible;
+use std::hash::Hash;
+use std::iter::empty;
+
+type SophiaQuad = ([Term; 3], Option<Term>);
+type StreamedSophiaQuad<'a> = StreamedQuad<'a, ByValue<SophiaQuad>>;
+
+/// Execute a SPARQL query in a store, and return the result as a HashSet,
+/// mapping the error (if any) through the given function.
+///
+/// # Precondition
+/// + the query must be a SELECT query with a single selected variable
+/// + it must not produce NULL results
+macro_rules! sparql_to_hashset {
+    ($store: ident, $err_map: ident, $sparql: expr) => {
+        //sparql_result_as_term_set($store, $sparql).map_err($err_map)
+        {
+            (|| -> Result<HashSet<Term>, EvaluationError> {
+                let q = $store.prepare_query($sparql, QueryOptions::default())?;
+                let r = q.exec()?;
+                if let QueryResults::Solutions(solutions) = r {
+                    solutions
+                        .map(|r| r.map(|v| v.get(0).unwrap().clone()))
+                        .collect()
+                } else {
+                    unreachable!()
+                }
+            })()
+            .map_err($err_map)
+        }
+    };
+}
+
+macro_rules! impl_dataset {
+    ($store: ident, $error: ty, $quad_map: ident, $err_map: ident) => {
+        impl Dataset for $store {
+            type Quad = ByValue<SophiaQuad>;
+            type Error = $error;
+
+            fn quads(&self) -> DQuadSource<'_, Self> {
+                Box::new(
+                    self.quads_for_pattern(None, None, None, None)
+                        .map($quad_map),
+                )
+            }
+            fn quads_with_s<'s, TS>(&'s self, s: &'s TS) -> DQuadSource<'s, Self>
+            where
+                TS: TTerm + ?Sized,
+            {
+                let mut buf_s = String::new();
+                let s = convert_subject(s, &mut buf_s);
+                if s.is_none() {
+                    Box::new(empty())
+                } else {
+                    Box::new(self.quads_for_pattern(s, None, None, None).map($quad_map))
+                }
+            }
+            fn quads_with_p<'s, TP>(&'s self, p: &'s TP) -> DQuadSource<'s, Self>
+            where
+                TP: TTerm + ?Sized,
+            {
+                let mut buf_p = String::new();
+                let p = convert_predicate(p, &mut buf_p);
+                if p.is_none() {
+                    Box::new(empty())
+                } else {
+                    Box::new(self.quads_for_pattern(None, p, None, None).map($quad_map))
+                }
+            }
+            fn quads_with_o<'s, TS>(&'s self, o: &'s TS) -> DQuadSource<'s, Self>
+            where
+                TS: TTerm + ?Sized,
+            {
+                let mut buf_o = String::new();
+                let o = convert_object(o, &mut buf_o);
+                if o.is_none() {
+                    Box::new(empty())
+                } else {
+                    Box::new(self.quads_for_pattern(None, None, o, None).map($quad_map))
+                }
+            }
+            fn quads_with_g<'s, TS>(&'s self, g: Option<&'s TS>) -> DQuadSource<'s, Self>
+            where
+                TS: TTerm + ?Sized,
+            {
+                let mut buf_g = String::new();
+                let g = convert_graph_name(g, &mut buf_g);
+                if g.is_none() {
+                    Box::new(empty())
+                } else {
+                    Box::new(self.quads_for_pattern(None, None, None, g).map($quad_map))
+                }
+            }
+            fn quads_with_sp<'s, TS, TP>(&'s self, s: &'s TS, p: &'s TP) -> DQuadSource<'s, Self>
+            where
+                TS: TTerm + ?Sized,
+                TP: TTerm + ?Sized,
+            {
+                let mut buf_s = String::new();
+                let s = convert_subject(s, &mut buf_s);
+                let mut buf_p = String::new();
+                let p = convert_predicate(p, &mut buf_p);
+                if s.is_none() || p.is_none() {
+                    Box::new(empty())
+                } else {
+                    Box::new(self.quads_for_pattern(s, p, None, None).map($quad_map))
+                }
+            }
+            fn quads_with_so<'s, TS, TO>(&'s self, s: &'s TS, o: &'s TO) -> DQuadSource<'s, Self>
+            where
+                TS: TTerm + ?Sized,
+                TO: TTerm + ?Sized,
+            {
+                let mut buf_s = String::new();
+                let s = convert_subject(s, &mut buf_s);
+                let mut buf_o = String::new();
+                let o = convert_object(o, &mut buf_o);
+                if s.is_none() || o.is_none() {
+                    Box::new(empty())
+                } else {
+                    Box::new(self.quads_for_pattern(s, None, o, None).map($quad_map))
+                }
+            }
+            fn quads_with_sg<'s, TS, TG>(
+                &'s self,
+                s: &'s TS,
+                g: Option<&'s TG>,
+            ) -> DQuadSource<'s, Self>
+            where
+                TS: TTerm + ?Sized,
+                TG: TTerm + ?Sized,
+            {
+                let mut buf_s = String::new();
+                let s = convert_subject(s, &mut buf_s);
+                let mut buf_g = String::new();
+                let g = convert_graph_name(g, &mut buf_g);
+                if s.is_none() || g.is_none() {
+                    Box::new(empty())
+                } else {
+                    Box::new(self.quads_for_pattern(s, None, None, g).map($quad_map))
+                }
+            }
+            fn quads_with_po<'s, TP, TO>(&'s self, p: &'s TP, o: &'s TO) -> DQuadSource<'s, Self>
+            where
+                TP: TTerm + ?Sized,
+                TO: TTerm + ?Sized,
+            {
+                let mut buf_p = String::new();
+                let p = convert_predicate(p, &mut buf_p);
+                let mut buf_o = String::new();
+                let o = convert_object(o, &mut buf_o);
+                if p.is_none() || o.is_none() {
+                    Box::new(empty())
+                } else {
+                    Box::new(self.quads_for_pattern(None, p, o, None).map($quad_map))
+                }
+            }
+            fn quads_with_pg<'s, TP, TG>(
+                &'s self,
+                p: &'s TP,
+                g: Option<&'s TG>,
+            ) -> DQuadSource<'s, Self>
+            where
+                TP: TTerm + ?Sized,
+                TG: TTerm + ?Sized,
+            {
+                let mut buf_p = String::new();
+                let p = convert_predicate(p, &mut buf_p);
+                let mut buf_g = String::new();
+                let g = convert_graph_name(g, &mut buf_g);
+                if p.is_none() || g.is_none() {
+                    Box::new(empty())
+                } else {
+                    Box::new(self.quads_for_pattern(None, p, None, g).map($quad_map))
+                }
+            }
+            fn quads_with_og<'s, TO, TG>(
+                &'s self,
+                o: &'s TO,
+                g: Option<&'s TG>,
+            ) -> DQuadSource<'s, Self>
+            where
+                TO: TTerm + ?Sized,
+                TG: TTerm + ?Sized,
+            {
+                let mut buf_o = String::new();
+                let o = convert_object(o, &mut buf_o);
+                let mut buf_g = String::new();
+                let g = convert_graph_name(g, &mut buf_g);
+                if o.is_none() || g.is_none() {
+                    Box::new(empty())
+                } else {
+                    Box::new(self.quads_for_pattern(None, None, o, g).map($quad_map))
+                }
+            }
+            fn quads_with_spo<'s, TS, TP, TO>(
+                &'s self,
+                s: &'s TS,
+                p: &'s TP,
+                o: &'s TO,
+            ) -> DQuadSource<'s, Self>
+            where
+                TS: TTerm + ?Sized,
+                TP: TTerm + ?Sized,
+                TO: TTerm + ?Sized,
+            {
+                let mut buf_s = String::new();
+                let s = convert_subject(s, &mut buf_s);
+                let mut buf_p = String::new();
+                let p = convert_predicate(p, &mut buf_p);
+                let mut buf_o = String::new();
+                let o = convert_object(o, &mut buf_o);
+                if s.is_none() || p.is_none() || o.is_none() {
+                    Box::new(empty())
+                } else {
+                    Box::new(self.quads_for_pattern(s, p, o, None).map($quad_map))
+                }
+            }
+            fn quads_with_spg<'s, TS, TP, TG>(
+                &'s self,
+                s: &'s TS,
+                p: &'s TP,
+                g: Option<&'s TG>,
+            ) -> DQuadSource<'s, Self>
+            where
+                TS: TTerm + ?Sized,
+                TP: TTerm + ?Sized,
+                TG: TTerm + ?Sized,
+            {
+                let mut buf_s = String::new();
+                let s = convert_subject(s, &mut buf_s);
+                let mut buf_p = String::new();
+                let p = convert_predicate(p, &mut buf_p);
+                let mut buf_g = String::new();
+                let g = convert_graph_name(g, &mut buf_g);
+                if s.is_none() || p.is_none() || g.is_none() {
+                    Box::new(empty())
+                } else {
+                    Box::new(self.quads_for_pattern(s, p, None, g).map($quad_map))
+                }
+            }
+            fn quads_with_sog<'s, TS, TO, TG>(
+                &'s self,
+                s: &'s TS,
+                o: &'s TO,
+                g: Option<&'s TG>,
+            ) -> DQuadSource<'s, Self>
+            where
+                TS: TTerm + ?Sized,
+                TO: TTerm + ?Sized,
+                TG: TTerm + ?Sized,
+            {
+                let mut buf_s = String::new();
+                let s = convert_subject(s, &mut buf_s);
+                let mut buf_o = String::new();
+                let o = convert_object(o, &mut buf_o);
+                let mut buf_g = String::new();
+                let g = convert_graph_name(g, &mut buf_g);
+                if s.is_none() || o.is_none() || g.is_none() {
+                    Box::new(empty())
+                } else {
+                    Box::new(self.quads_for_pattern(s, None, o, g).map($quad_map))
+                }
+            }
+            fn quads_with_pog<'s, TP, TO, TG>(
+                &'s self,
+                p: &'s TP,
+                o: &'s TO,
+                g: Option<&'s TG>,
+            ) -> DQuadSource<'s, Self>
+            where
+                TP: TTerm + ?Sized,
+                TO: TTerm + ?Sized,
+                TG: TTerm + ?Sized,
+            {
+                let mut buf_p = String::new();
+                let p = convert_predicate(p, &mut buf_p);
+                let mut buf_o = String::new();
+                let o = convert_object(o, &mut buf_o);
+                let mut buf_g = String::new();
+                let g = convert_graph_name(g, &mut buf_g);
+                if p.is_none() || o.is_none() || g.is_none() {
+                    Box::new(empty())
+                } else {
+                    Box::new(self.quads_for_pattern(None, p, o, g).map($quad_map))
+                }
+            }
+            fn quads_with_spog<'s, TS, TP, TO, TG>(
+                &'s self,
+                s: &'s TS,
+                p: &'s TP,
+                o: &'s TO,
+                g: Option<&'s TG>,
+            ) -> DQuadSource<'s, Self>
+            where
+                TS: TTerm + ?Sized,
+                TP: TTerm + ?Sized,
+                TO: TTerm + ?Sized,
+                TG: TTerm + ?Sized,
+            {
+                let mut buf_s = String::new();
+                let s = convert_subject(s, &mut buf_s);
+                let mut buf_p = String::new();
+                let p = convert_predicate(p, &mut buf_p);
+                let mut buf_o = String::new();
+                let o = convert_object(o, &mut buf_o);
+                let mut buf_g = String::new();
+                let g = convert_graph_name(g, &mut buf_g);
+                if s.is_none() || p.is_none() || o.is_none() || g.is_none() {
+                    Box::new(empty())
+                } else {
+                    Box::new(self.quads_for_pattern(s, p, o, g).map($quad_map))
+                }
+            }
+            fn subjects(&self) -> DResultTermSet<Self>
+            where
+                DTerm<Self>: Clone + Eq + Hash,
+            {
+                sparql_to_hashset!(
+                    self,
+                    $err_map,
+                    "SELECT DISTINCT ?s {{?s ?p ?o} UNION { GRAPH ?g {?s ?p ?o}}}"
+                )
+            }
+            fn predicates(&self) -> DResultTermSet<Self>
+            where
+                DTerm<Self>: Clone + Eq + Hash,
+            {
+                sparql_to_hashset!(
+                    self,
+                    $err_map,
+                    "SELECT DISTINCT ?p {{?s ?p ?o} UNION { GRAPH ?g {?s ?p ?o}}}"
+                )
+            }
+            fn objects(&self) -> DResultTermSet<Self>
+            where
+                DTerm<Self>: Clone + Eq + Hash,
+            {
+                sparql_to_hashset!(
+                    self,
+                    $err_map,
+                    "SELECT DISTINCT ?o {{?s ?p ?o} UNION { GRAPH ?g {?s ?p ?o}}}"
+                )
+            }
+            fn graph_names(&self) -> DResultTermSet<Self>
+            where
+                DTerm<Self>: Clone + Eq + Hash,
+            {
+                sparql_to_hashset!(self, $err_map, "SELECT DISTINCT ?g {GRAPH ?g {?s ?p ?o}}")
+            }
+            fn iris(&self) -> DResultTermSet<Self>
+            where
+                DTerm<Self>: Clone + Eq + Hash,
+            {
+                sparql_to_hashset!(
+                    self,
+                    $err_map,
+                    "SELECT DISTINCT ?iri {
+                        {?iri ?p ?o} UNION
+                        {?s ?iri ?o} UNION
+                        {?s ?p ?iri} UNION
+                        {GRAPH ?iri {?s ?p ?o}} UNION
+                        {GRAPH ?s {?iri ?p ?o}} UNION
+                        {GRAPH ?g {?s ?iri ?o}} UNION
+                        {GRAPH ?g {?s ?p ?iri}}
+                        FILTER isIRI(?iri)
+                    }"
+                )
+            }
+            fn bnodes(&self) -> DResultTermSet<Self>
+            where
+                DTerm<Self>: Clone + Eq + Hash,
+            {
+                sparql_to_hashset!(
+                    self,
+                    $err_map,
+                    "SELECT DISTINCT ?bn {
+                        {?bn ?p ?o} UNION
+                        {?s ?p ?bn} UNION
+                        {GRAPH ?bn {?s ?p ?o}} UNION
+                        {GRAPH ?s {?bn ?p ?o}} UNION
+                        {GRAPH ?g {?s ?p ?bn}}
+                        FILTER isBlank(?bn)
+                    }"
+                )
+            }
+            fn literals(&self) -> DResultTermSet<Self>
+            where
+                DTerm<Self>: Clone + Eq + Hash,
+            {
+                sparql_to_hashset!(
+                    self,
+                    $err_map,
+                    "SELECT DISTINCT ?lit {
+                        {?s ?p ?lit} UNION
+                        { GRAPH ?g {?s ?p ?lit}}
+                        FILTER isLiteral(?lit)
+                    }"
+                )
+            }
+            fn variables(&self) -> DResultTermSet<Self>
+            where
+                DTerm<Self>: Clone + Eq + Hash,
+            {
+                Ok(std::collections::HashSet::new())
+            }
+        }
+    };
+}
+
+mod mem {
+    use super::*;
+
+    impl_dataset!(
+        MemoryStore,
+        Infallible,
+        infallible_quad_map,
+        infallible_err_map
+    );
+
+    impl MutableDataset for MemoryStore {
+        type MutationError = Infallible;
+        fn insert<TS, TP, TO, TG>(
+            &mut self,
+            s: &TS,
+            p: &TP,
+            o: &TO,
+            g: Option<&TG>,
+        ) -> MDResult<Self, bool>
+        where
+            TS: TTerm + ?Sized,
+            TP: TTerm + ?Sized,
+            TO: TTerm + ?Sized,
+            TG: TTerm + ?Sized,
+        {
+            let quad = match convert_quad(s, p, o, g) {
+                Some(quad) => quad,
+                None => return Ok(false),
+            };
+            MemoryStore::insert(self, quad);
+            Ok(true)
+        }
+
+        fn remove<TS, TP, TO, TG>(
+            &mut self,
+            s: &TS,
+            p: &TP,
+            o: &TO,
+            g: Option<&TG>,
+        ) -> MDResult<Self, bool>
+        where
+            TS: TTerm + ?Sized,
+            TP: TTerm + ?Sized,
+            TO: TTerm + ?Sized,
+            TG: TTerm + ?Sized,
+        {
+            let mut buf_s = String::new();
+            let mut buf_p = String::new();
+            let mut buf_o = String::new();
+            let mut buf_g = String::new();
+            let quadref =
+                match convert_quadref(s, p, o, g, &mut buf_s, &mut buf_p, &mut buf_o, &mut buf_g) {
+                    Some(quad) => quad,
+                    None => return Ok(false),
+                };
+            MemoryStore::remove(self, quadref);
+            Ok(true)
+        }
+    }
+
+    impl CollectibleDataset for MemoryStore {
+        fn from_quad_source<QS: QuadSource>(
+            quads: QS,
+        ) -> StreamResult<Self, QS::Error, Self::Error> {
+            let mut d = MemoryStore::new();
+            d.insert_all(quads)?;
+            Ok(d)
+        }
+    }
+
+    #[cfg(test)]
+    sophia_api::test_dataset_impl!(test, MemoryStore, false, false);
+}
+
+#[cfg(feature = "sled")]
+mod sled {
+    use super::*;
+
+    impl_dataset!(SledStore, std::io::Error, io_quad_map, io_err_map);
+
+    impl MutableDataset for SledStore {
+        type MutationError = std::io::Error;
+        fn insert<TS, TP, TO, TG>(
+            &mut self,
+            s: &TS,
+            p: &TP,
+            o: &TO,
+            g: Option<&TG>,
+        ) -> MDResult<Self, bool>
+        where
+            TS: TTerm + ?Sized,
+            TP: TTerm + ?Sized,
+            TO: TTerm + ?Sized,
+            TG: TTerm + ?Sized,
+        {
+            let mut buf_s = String::new();
+            let mut buf_p = String::new();
+            let mut buf_o = String::new();
+            let mut buf_g = String::new();
+            let quadref =
+                match convert_quadref(s, p, o, g, &mut buf_s, &mut buf_p, &mut buf_o, &mut buf_g) {
+                    Some(quad) => quad,
+                    None => return Ok(false),
+                };
+            SledStore::insert(self, quadref).map(|_| true)
+        }
+
+        fn remove<TS, TP, TO, TG>(
+            &mut self,
+            s: &TS,
+            p: &TP,
+            o: &TO,
+            g: Option<&TG>,
+        ) -> MDResult<Self, bool>
+        where
+            TS: TTerm + ?Sized,
+            TP: TTerm + ?Sized,
+            TO: TTerm + ?Sized,
+            TG: TTerm + ?Sized,
+        {
+            let mut buf_s = String::new();
+            let mut buf_p = String::new();
+            let mut buf_o = String::new();
+            let mut buf_g = String::new();
+            let quadref =
+                match convert_quadref(s, p, o, g, &mut buf_s, &mut buf_p, &mut buf_o, &mut buf_g) {
+                    Some(quad) => quad,
+                    None => return Ok(false),
+                };
+            SledStore::remove(self, quadref).map(|_| true)
+        }
+    }
+
+    impl CollectibleDataset for SledStore {
+        fn from_quad_source<QS: QuadSource>(
+            quads: QS,
+        ) -> StreamResult<Self, QS::Error, Self::Error> {
+            let mut d =
+                SledStore::new().map_err(sophia_api::quad::stream::StreamError::SinkError)?;
+            d.insert_all(quads)?;
+            Ok(d)
+        }
+    }
+
+    #[cfg(test)]
+    sophia_api::test_dataset_impl!(test, SledStore, false, false);
+}
+
+#[cfg(feature = "rocksdb")]
+mod rocksdb {
+    use super::*;
+    impl_dataset!(RocksDbStore, std::io::Error, io_quad_map, io_err_map);
+
+    impl MutableDataset for RocksDbStore {
+        type MutationError = std::io::Error;
+        fn insert<TS, TP, TO, TG>(
+            &mut self,
+            s: &TS,
+            p: &TP,
+            o: &TO,
+            g: Option<&TG>,
+        ) -> MDResult<Self, bool>
+        where
+            TS: TTerm + ?Sized,
+            TP: TTerm + ?Sized,
+            TO: TTerm + ?Sized,
+            TG: TTerm + ?Sized,
+        {
+            let mut buf_s = String::new();
+            let mut buf_p = String::new();
+            let mut buf_o = String::new();
+            let mut buf_g = String::new();
+            let quadref =
+                match convert_quadref(s, p, o, g, &mut buf_s, &mut buf_p, &mut buf_o, &mut buf_g) {
+                    Some(quad) => quad,
+                    None => return Ok(false),
+                };
+            RocksDbStore::insert(self, quadref).map(|_| true)
+        }
+
+        fn remove<TS, TP, TO, TG>(
+            &mut self,
+            s: &TS,
+            p: &TP,
+            o: &TO,
+            g: Option<&TG>,
+        ) -> MDResult<Self, bool>
+        where
+            TS: TTerm + ?Sized,
+            TP: TTerm + ?Sized,
+            TO: TTerm + ?Sized,
+            TG: TTerm + ?Sized,
+        {
+            let mut buf_s = String::new();
+            let mut buf_p = String::new();
+            let mut buf_o = String::new();
+            let mut buf_g = String::new();
+            let quadref =
+                match convert_quadref(s, p, o, g, &mut buf_s, &mut buf_p, &mut buf_o, &mut buf_g) {
+                    Some(quad) => quad,
+                    None => return Ok(false),
+                };
+            RocksDbStore::remove(self, quadref).map(|_| true)
+        }
+    }
+}
+
+// helper functions
+
+fn infallible_quad_map<'a>(q: Quad) -> Result<StreamedSophiaQuad<'a>, Infallible> {
+    let q: SophiaQuad = q.into();
+    Ok(StreamedQuad::by_value(q))
+}
+
+fn infallible_err_map(_: EvaluationError) -> Infallible {
+    panic!("Unexpected error")
+}
+
+#[cfg(any(feature = "rocksdb", feature = "sled"))]
+fn io_quad_map<'a>(
+    res: Result<Quad, std::io::Error>,
+) -> Result<StreamedSophiaQuad<'a>, std::io::Error> {
+    res.map(|q| {
+        let q: SophiaQuad = q.into();
+        StreamedQuad::by_value(q)
+    })
+}
+
+#[cfg(any(feature = "rocksdb", feature = "sled"))]
+fn io_err_map(err: EvaluationError) -> std::io::Error {
+    match err {
+        EvaluationError::Io(err) => err,
+        _ => panic!("Unexpected error"),
+    }
+}
+
+fn convert_subject<'a, T>(term: &'a T, buffer: &'a mut String) -> Option<NamedOrBlankNodeRef<'a>>
+where
+    T: TTerm + ?Sized + 'a,
+{
+    match term.kind() {
+        TermKind::Iri => Some(convert_iri(term, buffer).into()),
+        TermKind::BlankNode => Some(BlankNodeRef::new_unchecked(term.value_raw().0).into()),
+        _ => None,
+    }
+}
+
+fn convert_predicate<'a, T>(term: &'a T, buffer: &'a mut String) -> Option<NamedNodeRef<'a>>
+where
+    T: TTerm + ?Sized + 'a,
+{
+    match term.kind() {
+        TermKind::Iri => Some(convert_iri(term, buffer)),
+        _ => None,
+    }
+}
+
+fn convert_object<'a, T>(term: &'a T, buffer: &'a mut String) -> Option<TermRef<'a>>
+where
+    T: TTerm + ?Sized + 'a,
+{
+    match term.kind() {
+        TermKind::Iri => Some(convert_iri(term, buffer).into()),
+        TermKind::BlankNode => Some(BlankNodeRef::new_unchecked(term.value_raw().0).into()),
+        TermKind::Literal => {
+            let value = term.value_raw().0;
+            let lit = match term.language() {
+                Some(tag) => LiteralRef::new_language_tagged_literal_unchecked(value, tag),
+                None => {
+                    let (ns, suffix) = term.datatype().unwrap().destruct();
+                    let datatype = convert_iri_raw(ns, suffix, buffer);
+                    LiteralRef::new_typed_literal(value, datatype)
+                }
+            };
+            Some(lit.into())
+        }
+        _ => None,
+    }
+}
+
+fn convert_graph_name<'a, T>(
+    graph_name: Option<&'a T>,
+    buffer: &'a mut String,
+) -> Option<GraphNameRef<'a>>
+where
+    T: TTerm + ?Sized + 'a,
+{
+    match graph_name {
+        None => Some(GraphNameRef::DefaultGraph),
+        Some(term) => match term.kind() {
+            TermKind::Iri => Some(convert_iri(term, buffer).into()),
+            TermKind::BlankNode => Some(BlankNodeRef::new_unchecked(term.value_raw().0).into()),
+            _ => None,
+        },
+    }
+}
+
+fn convert_iri<'a, T>(term: &'a T, buffer: &'a mut String) -> NamedNodeRef<'a>
+where
+    T: TTerm + ?Sized + 'a,
+{
+    debug_assert_eq!(term.kind(), TermKind::Iri);
+    let raw = term.value_raw();
+    convert_iri_raw(raw.0, raw.1, buffer)
+}
+
+fn convert_iri_raw<'a>(
+    ns: &'a str,
+    suffix: Option<&'a str>,
+    buffer: &'a mut String,
+) -> NamedNodeRef<'a> {
+    let iri: &'a str = match suffix {
+        Some(suffix) => {
+            buffer.clear();
+            buffer.push_str(ns);
+            buffer.push_str(suffix);
+            buffer
+        }
+        None => ns,
+    };
+    NamedNodeRef::new_unchecked(iri)
+}
+
+fn convert_quad<TS, TP, TO, TG>(s: &TS, p: &TP, o: &TO, g: Option<&TG>) -> Option<Quad>
+where
+    TS: TTerm + ?Sized,
+    TP: TTerm + ?Sized,
+    TO: TTerm + ?Sized,
+    TG: TTerm + ?Sized,
+{
+    let s = match NamedOrBlankNode::try_copy(s) {
+        Ok(s) => s,
+        Err(_) => return None,
+    };
+    let p = match NamedNode::try_copy(p) {
+        Ok(p) => p,
+        Err(_) => return None,
+    };
+    let o = match Term::try_copy(o) {
+        Ok(o) => o,
+        Err(_) => return None,
+    };
+    let g = match g {
+        None => GraphName::DefaultGraph,
+        Some(g) => match NamedOrBlankNode::try_copy(g) {
+            Ok(g) => g.into(),
+            Err(_) => return None,
+        },
+    };
+    Some(Quad::new(s, p, o, g))
+}
+
+fn convert_quadref<'a, TS, TP, TO, TG>(
+    s: &'a TS,
+    p: &'a TP,
+    o: &'a TO,
+    g: Option<&'a TG>,
+    buf_s: &'a mut String,
+    buf_p: &'a mut String,
+    buf_o: &'a mut String,
+    buf_g: &'a mut String,
+) -> Option<QuadRef<'a>>
+where
+    TS: TTerm + ?Sized,
+    TP: TTerm + ?Sized,
+    TO: TTerm + ?Sized,
+    TG: TTerm + ?Sized,
+{
+    let s = match convert_subject(s, buf_s) {
+        Some(s) => s,
+        None => return None,
+    };
+    let p = match convert_predicate(p, buf_p) {
+        Some(p) => p,
+        None => return None,
+    };
+    let o = match convert_object(o, buf_o) {
+        Some(o) => o,
+        None => return None,
+    };
+    let g = match convert_graph_name(g, buf_g) {
+        Some(g) => g,
+        None => return None,
+    };
+    Some(QuadRef::new(s, p, o, g))
+}