diff --git a/REQUIRE b/REQUIRE
index 3eba29b..c7eded8 100644
--- a/REQUIRE
+++ b/REQUIRE
@@ -1,2 +1,2 @@
 julia 0.4
-Compat 0.9.2
+Compat 0.17.0
diff --git a/src/PDMats.jl b/src/PDMats.jl
index 216e8bf..bfaafef 100644
--- a/src/PDMats.jl
+++ b/src/PDMats.jl
@@ -5,7 +5,7 @@ module PDMats
     using Compat
 
     import Base: +, *, \, /, ==
-    import Base: full, logdet, inv, diag, diagm, scale, scale!, eigmax, eigmin, convert
+    import Base: full, logdet, inv, diag, diagm, eigmax, eigmin, convert
 
     export
         # Types
@@ -43,7 +43,7 @@ module PDMats
 
     # The abstract base type
 
-    abstract AbstractPDMat{T<:Real}
+    @compat abstract type AbstractPDMat{T<:Real} end
 
     # source files
 
diff --git a/src/pdiagmat.jl b/src/pdiagmat.jl
index d49c871..cfc5821 100644
--- a/src/pdiagmat.jl
+++ b/src/pdiagmat.jl
@@ -1,10 +1,10 @@
 # positive diagonal matrix
 
-immutable PDiagMat{T<:Real,V<:AbstractVector} <: AbstractPDMat{T}
+@compat immutable PDiagMat{T<:Real,V<:AbstractVector} <: AbstractPDMat{T}
   dim::Int
   diag::V
   inv_diag::V
-  PDiagMat(d::Int,v::AbstractVector{T},inv_v::AbstractVector{T}) = new(d,v,inv_v)
+  (::Type{PDiagMat{T,S}}){T,S}(d::Int,v::AbstractVector{T},inv_v::AbstractVector{T}) = new{T,S}(d,v,inv_v)
 end
 
 function PDiagMat(v::AbstractVector,inv_v::AbstractVector)
diff --git a/src/pdmat.jl b/src/pdmat.jl
index af8927c..ef5924c 100644
--- a/src/pdmat.jl
+++ b/src/pdmat.jl
@@ -1,9 +1,9 @@
 # Full positive definite matrix together with a Cholesky factorization object
-immutable PDMat{T<:Real,S<:AbstractMatrix} <: AbstractPDMat{T}
+@compat immutable PDMat{T<:Real,S<:AbstractMatrix} <: AbstractPDMat{T}
     dim::Int
     mat::S
     chol::CholType{T,S}
-    PDMat(d::Int,m::AbstractMatrix{T},c::CholType{T,S}) = new(d,m,c)
+    (::Type{PDMat{T,S}}){T,S}(d::Int,m::AbstractMatrix{T},c::CholType{T,S}) = new{T,S}(d,m,c)
 end
 
 function PDMat(mat::AbstractMatrix,chol::CholType)
diff --git a/src/pdsparsemat.jl b/src/pdsparsemat.jl
index 892c495..148d45c 100644
--- a/src/pdsparsemat.jl
+++ b/src/pdsparsemat.jl
@@ -1,9 +1,9 @@
 # Sparse positive definite matrix together with a Cholesky factorization object
-immutable PDSparseMat{T<:Real,S<:AbstractSparseMatrix} <: AbstractPDMat{T}
+@compat immutable PDSparseMat{T<:Real,S<:AbstractSparseMatrix} <: AbstractPDMat{T}
   dim::Int
   mat::S
   chol::CholTypeSparse
-  PDSparseMat(d::Int,m::AbstractSparseMatrix{T},c::CholTypeSparse) = new(d,m,c) #add {T} to CholTypeSparse argument once #14076 is implemented
+  (::Type{PDSparseMat{T,S}}){T,S}(d::Int,m::AbstractSparseMatrix{T},c::CholTypeSparse) = new{T,S}(d,m,c) #add {T} to CholTypeSparse argument once #14076 is implemented
 end
 
 function PDSparseMat(mat::AbstractSparseMatrix,chol::CholTypeSparse)