diff --git a/src/catala/default_calculus/ast.ml b/src/catala/default_calculus/ast.ml
index a0cd9dc6..abd7e06f 100644
--- a/src/catala/default_calculus/ast.ml
+++ b/src/catala/default_calculus/ast.ml
@@ -34,9 +34,22 @@ type expr =
 module Var = struct
   type t = expr Pos.marked Bindlib.var
 
+  let make (s : string Pos.marked) =
+    Bindlib.new_var (fun x -> (EVar x, Pos.get_position s)) (Pos.unmark s)
+
   let compare x y = Bindlib.compare_vars x y
 end
 
 module VarMap = Map.Make (Var)
 
+let make_var (x : Var.t) : expr Pos.marked Bindlib.box = Bindlib.box_var x
+
+let make_abs (x : Var.t) (e : expr Pos.marked Bindlib.box) (pos_binder : Pos.t) (tau : typ)
+    (pos : Pos.t) : expr Pos.marked Bindlib.box =
+  Bindlib.box_apply (fun b -> (EAbs (pos_binder, b, tau), pos)) (Bindlib.bind_var x e)
+
+let make_app (e : expr Pos.marked Bindlib.box) (u : expr Pos.marked Bindlib.box) (pos : Pos.t) :
+    expr Pos.marked Bindlib.box =
+  Bindlib.box_apply2 (fun e u -> (EApp (e, u), pos)) e u
+
 type binder = (expr, expr Pos.marked) Bindlib.binder
diff --git a/src/catala/scope_language/ast.ml b/src/catala/scope_language/ast.ml
index 7e8c7438..903afce8 100644
--- a/src/catala/scope_language/ast.ml
+++ b/src/catala/scope_language/ast.ml
@@ -24,7 +24,9 @@ module ScopeVar = Uid.Make (Uid.MarkedString)
 module ScopeVarSet = Set.Make (ScopeVar)
 module ScopeVarMap = Map.Make (ScopeVar)
 
-type location = ScopeVar of ScopeVar.t | SubScopeVar of ScopeName.t * SubScopeName.t * ScopeVar.t
+type location =
+  | ScopeVar of ScopeVar.t Pos.marked
+  | SubScopeVar of ScopeName.t * SubScopeName.t Pos.marked * ScopeVar.t Pos.marked
 
 type expr =
   | ELocation of location
@@ -34,7 +36,20 @@ type expr =
   | EApp of expr Pos.marked * expr Pos.marked
   | EDefault of expr Pos.marked * expr Pos.marked * expr Pos.marked list
 
-type rule = Definition of location * Dcalc.Ast.typ * expr | Call of ScopeName.t * SubScopeName.t
+module Var = struct
+  type t = expr Pos.marked Bindlib.var
+
+  let make (s : string Pos.marked) =
+    Bindlib.new_var (fun x -> (EVar x, Pos.get_position s)) (Pos.unmark s)
+
+  let compare x y = Bindlib.compare_vars x y
+end
+
+module VarMap = Map.Make (Var)
+
+type rule =
+  | Definition of location * Dcalc.Ast.typ * expr Pos.marked
+  | Call of ScopeName.t * SubScopeName.t
 
 type scope_decl = { scope_decl_name : ScopeName.t; scope_decl_rules : rule list }
 
diff --git a/src/catala/scope_language/scope_to_dcalc.ml b/src/catala/scope_language/scope_to_dcalc.ml
index 9fb8a0ff..9daaf970 100644
--- a/src/catala/scope_language/scope_to_dcalc.ml
+++ b/src/catala/scope_language/scope_to_dcalc.ml
@@ -13,20 +13,117 @@
    the License. *)
 
 module Pos = Utils.Pos
+module Errors = Utils.Errors
 
-type ctx = Ast.location list
+type ctx = {
+  scope_vars : (Dcalc.Ast.Var.t * Dcalc.Ast.typ) Ast.ScopeVarMap.t;
+  subscope_vars : (Dcalc.Ast.Var.t * Dcalc.Ast.typ) Ast.ScopeVarMap.t Ast.SubScopeMap.t;
+  local_vars : Dcalc.Ast.Var.t Ast.VarMap.t;
+}
+
+let empty_ctx =
+  {
+    scope_vars = Ast.ScopeVarMap.empty;
+    subscope_vars = Ast.SubScopeMap.empty;
+    local_vars = Ast.VarMap.empty;
+  }
 
 type scope_ctx = Dcalc.Ast.Var.t Ast.ScopeMap.t
 
-let hole_var : Dcalc.Ast.Var.t = Bindlib.new_var (fun x -> (Dcalc.Ast.EVar x, Pos.no_pos)) "hole"
+let hole_var : Dcalc.Ast.Var.t = Dcalc.Ast.Var.make ("hole", Pos.no_pos)
 
-let translate_rules (_p : scope_ctx) (_ctx : ctx) (_rules : Ast.rule list) : Dcalc.Ast.expr * ctx =
-  assert false
+let merge_operator_var : Dcalc.Ast.Var.t = Dcalc.Ast.Var.make ("merge", Pos.no_pos)
 
-let translate_scope_decl (p : scope_ctx) (sigma : Ast.scope_decl) : Dcalc.Ast.expr =
-  let ctx = [] in
-  let _defs, ctx = translate_rules p ctx sigma.scope_decl_rules in
-  let _scope_variables =
-    List.filter_map (fun l -> match l with Ast.ScopeVar v -> Some v | _ -> None) ctx
+let merge_operator_expr : Dcalc.Ast.expr Pos.marked Bindlib.box = Bindlib.box_var merge_operator_var
+
+let hole_expr : Dcalc.Ast.expr Pos.marked Bindlib.box = Bindlib.box_var hole_var
+
+let rec translate_expr (ctx : ctx) (e : Ast.expr Pos.marked) : Dcalc.Ast.expr Pos.marked =
+  Pos.same_pos_as
+    ( match Pos.unmark e with
+    | EVar v -> Dcalc.Ast.EVar (Ast.VarMap.find v ctx.local_vars)
+    | ELit l -> Dcalc.Ast.ELit l
+    | EApp (e1, e2) -> Dcalc.Ast.EApp (translate_expr ctx e1, translate_expr ctx e2)
+    | EAbs (pos_binder, binder, typ) ->
+        let x, body = Bindlib.unbind binder in
+        let new_x = Dcalc.Ast.Var.make (Bindlib.name_of x, pos_binder) in
+        let body =
+          translate_expr { ctx with local_vars = Ast.VarMap.add x new_x ctx.local_vars } body
+        in
+        let binder = Bindlib.unbox (Bindlib.bind_var new_x (Bindlib.box body)) in
+        Dcalc.Ast.EAbs (pos_binder, binder, typ)
+    | EDefault (just, cons, subs) ->
+        Dcalc.Ast.EDefault
+          (translate_expr ctx just, translate_expr ctx cons, List.map (translate_expr ctx) subs)
+    | ELocation (ScopeVar a) ->
+        Dcalc.Ast.EVar (fst (Ast.ScopeVarMap.find (Pos.unmark a) ctx.scope_vars))
+    | ELocation (SubScopeVar (_, s, a)) ->
+        Dcalc.Ast.EVar
+          (fst
+             (Ast.ScopeVarMap.find (Pos.unmark a)
+                (Ast.SubScopeMap.find (Pos.unmark s) ctx.subscope_vars))) )
+    e
+
+let translate_rule (_p : scope_ctx) (ctx : ctx) (rule : Ast.rule) :
+    Dcalc.Ast.expr Pos.marked Bindlib.box * ctx =
+  match rule with
+  | Definition (ScopeVar a, tau, e) ->
+      let a_name = Ast.ScopeVar.get_info (Pos.unmark a) in
+      let a_var = Dcalc.Ast.Var.make a_name in
+      let next_e =
+        Dcalc.Ast.make_abs a_var hole_expr (Pos.get_position a) tau (Pos.get_position e)
+      in
+      let silent1 = Dcalc.Ast.Var.make ("silent", Pos.get_position e) in
+      let silent2 = Dcalc.Ast.Var.make ("silent", Pos.get_position e) in
+      let wrapped_e =
+        Dcalc.Ast.make_abs silent1
+          (Bindlib.box (translate_expr ctx e))
+          (Pos.get_position e) Dcalc.Ast.TUnit (Pos.get_position e)
+      in
+      let a_expr = Dcalc.Ast.make_var a_var in
+      let merged_expr = Dcalc.Ast.make_app merge_operator_expr a_expr (Pos.get_position e) in
+      let merged_expr = Dcalc.Ast.make_app merged_expr wrapped_e (Pos.get_position e) in
+      let merged_thunked =
+        Dcalc.Ast.make_abs silent2 merged_expr (Pos.get_position e) Dcalc.Ast.TUnit
+          (Pos.get_position e)
+      in
+      let final_e = Dcalc.Ast.make_app merged_thunked next_e (Pos.get_position e) in
+      let new_ctx =
+        { ctx with scope_vars = Ast.ScopeVarMap.add (Pos.unmark a) (a_var, tau) ctx.scope_vars }
+      in
+      (final_e, new_ctx)
+  | Definition (SubScopeVar _, _tau, _e) ->
+      Errors.raise_error "translation of subscope vars definitions unimplemented"
+  | Call _ -> Errors.raise_error "translation of subscope calls unimplemented"
+
+let translate_rules (p : scope_ctx) (ctx : ctx) (rules : Ast.rule list) :
+    Dcalc.Ast.expr Pos.marked Bindlib.box * ctx =
+  let acc = hole_expr in
+  List.fold_left
+    (fun (acc, ctx) rule ->
+      let new_e, ctx = translate_rule p ctx rule in
+      let acc = Bindlib.unbox (Bindlib.bind_var hole_var acc) in
+      let new_acc = Bindlib.subst acc (Bindlib.unbox new_e) in
+      (Bindlib.box new_acc, ctx))
+    (acc, ctx) rules
+
+let translate_scope_decl (p : scope_ctx) (sigma : Ast.scope_decl) : Dcalc.Ast.expr Pos.marked =
+  let ctx = empty_ctx in
+  let rules, ctx = translate_rules p ctx sigma.scope_decl_rules in
+  let scope_variables = Ast.ScopeVarMap.bindings ctx.scope_vars in
+  let pos_sigma = Pos.get_position (Ast.ScopeName.get_info sigma.scope_decl_name) in
+  let return_exp =
+    Dcalc.Ast.ETuple
+      (List.map (fun (_, (dcalc_var, _)) -> (Dcalc.Ast.EVar dcalc_var, pos_sigma)) scope_variables)
   in
-  assert false
+  let func_acc = rules in
+  let func_acc =
+    List.fold_right
+      (fun (_, (dcalc_var, tau)) func_acc ->
+        Dcalc.Ast.make_abs dcalc_var func_acc pos_sigma
+          (Dcalc.Ast.TArrow ((Dcalc.Ast.TUnit, pos_sigma), (tau, pos_sigma)))
+          pos_sigma)
+      scope_variables func_acc
+  in
+  let func_acc = Bindlib.unbox (Bindlib.bind_var hole_var func_acc) in
+  Bindlib.subst func_acc (return_exp, pos_sigma)