diff --git a/build.sbt b/build.sbt
index 91b192f..a533b1e 100644
--- a/build.sbt
+++ b/build.sbt
@@ -8,6 +8,13 @@
 
 ThisBuild / scalaVersion := scala3Version
 
+lazy val proof = entityProject("proof", file("domain/proof"))
+  .components(_.dependsOn(ui))
+  .model(_.dependsOn(core))
+  .json(_.dependsOn(json))
+  .repo(_.dependsOn(`mongo-support`))
+  .endpoints(_.dependsOn(`tapir-support`))
+
 lazy val parameters = entityProject("parameters", file("domain/parameters"))
   .components(_.dependsOn(ui))
   .model(_.dependsOn(core))
@@ -55,6 +62,16 @@
   .jsSettings(IWDeps.tapirSttpClient)
   .jvmSettings(IWDeps.tapirZIO, IWDeps.tapirZIOHttp4sServer)
 
+lazy val `mongo-support` = project
+  .in(file("fiftyforms/mongo"))
+  .settings(
+    IWDeps.useZIO(Test),
+    IWDeps.zioJson,
+    IWDeps.zioConfig,
+    libraryDependencies += ("org.mongodb.scala" %% "mongo-scala-driver" % "4.2.3")
+      .cross(CrossVersion.for3Use2_13)
+  )
+
 lazy val app = (project in file("app"))
   .enablePlugins(ScalaJSPlugin, VitePlugin)
   .settings(
@@ -85,6 +102,8 @@
     parameters.command.client,
     users.query.client,
     users.command.client,
+    proof.query.client,
+    proof.command.client,
     endpoints.js
   )
 
@@ -134,6 +153,8 @@
     parameters.command.api,
     users.query.api,
     users.command.api,
+    proof.query.api,
+    proof.command.api,
     endpoints.jvm
   )
 

diff --git a/build.sbt b/build.sbt
index 91b192f..a533b1e 100644
--- a/build.sbt
+++ b/build.sbt
@@ -8,6 +8,13 @@
 
 ThisBuild / scalaVersion := scala3Version
 
+lazy val proof = entityProject("proof", file("domain/proof"))
+  .components(_.dependsOn(ui))
+  .model(_.dependsOn(core))
+  .json(_.dependsOn(json))
+  .repo(_.dependsOn(`mongo-support`))
+  .endpoints(_.dependsOn(`tapir-support`))
+
 lazy val parameters = entityProject("parameters", file("domain/parameters"))
   .components(_.dependsOn(ui))
   .model(_.dependsOn(core))
@@ -55,6 +62,16 @@
   .jsSettings(IWDeps.tapirSttpClient)
   .jvmSettings(IWDeps.tapirZIO, IWDeps.tapirZIOHttp4sServer)
 
+lazy val `mongo-support` = project
+  .in(file("fiftyforms/mongo"))
+  .settings(
+    IWDeps.useZIO(Test),
+    IWDeps.zioJson,
+    IWDeps.zioConfig,
+    libraryDependencies += ("org.mongodb.scala" %% "mongo-scala-driver" % "4.2.3")
+      .cross(CrossVersion.for3Use2_13)
+  )
+
 lazy val app = (project in file("app"))
   .enablePlugins(ScalaJSPlugin, VitePlugin)
   .settings(
@@ -85,6 +102,8 @@
     parameters.command.client,
     users.query.client,
     users.command.client,
+    proof.query.client,
+    proof.command.client,
     endpoints.js
   )
 
@@ -134,6 +153,8 @@
     parameters.command.api,
     users.query.api,
     users.command.api,
+    proof.query.api,
+    proof.command.api,
     endpoints.jvm
   )
 
diff --git a/core/src/main/scala/mdr/pdb/DocumentRef.scala b/core/src/main/scala/mdr/pdb/DocumentRef.scala
new file mode 100644
index 0000000..42d4108
--- /dev/null
+++ b/core/src/main/scala/mdr/pdb/DocumentRef.scala
@@ -0,0 +1,3 @@
+package mdr.pdb
+
+type DocumentRef = String

diff --git a/build.sbt b/build.sbt
index 91b192f..a533b1e 100644
--- a/build.sbt
+++ b/build.sbt
@@ -8,6 +8,13 @@
 
 ThisBuild / scalaVersion := scala3Version
 
+lazy val proof = entityProject("proof", file("domain/proof"))
+  .components(_.dependsOn(ui))
+  .model(_.dependsOn(core))
+  .json(_.dependsOn(json))
+  .repo(_.dependsOn(`mongo-support`))
+  .endpoints(_.dependsOn(`tapir-support`))
+
 lazy val parameters = entityProject("parameters", file("domain/parameters"))
   .components(_.dependsOn(ui))
   .model(_.dependsOn(core))
@@ -55,6 +62,16 @@
   .jsSettings(IWDeps.tapirSttpClient)
   .jvmSettings(IWDeps.tapirZIO, IWDeps.tapirZIOHttp4sServer)
 
+lazy val `mongo-support` = project
+  .in(file("fiftyforms/mongo"))
+  .settings(
+    IWDeps.useZIO(Test),
+    IWDeps.zioJson,
+    IWDeps.zioConfig,
+    libraryDependencies += ("org.mongodb.scala" %% "mongo-scala-driver" % "4.2.3")
+      .cross(CrossVersion.for3Use2_13)
+  )
+
 lazy val app = (project in file("app"))
   .enablePlugins(ScalaJSPlugin, VitePlugin)
   .settings(
@@ -85,6 +102,8 @@
     parameters.command.client,
     users.query.client,
     users.command.client,
+    proof.query.client,
+    proof.command.client,
     endpoints.js
   )
 
@@ -134,6 +153,8 @@
     parameters.command.api,
     users.query.api,
     users.command.api,
+    proof.query.api,
+    proof.command.api,
     endpoints.jvm
   )
 
diff --git a/core/src/main/scala/mdr/pdb/DocumentRef.scala b/core/src/main/scala/mdr/pdb/DocumentRef.scala
new file mode 100644
index 0000000..42d4108
--- /dev/null
+++ b/core/src/main/scala/mdr/pdb/DocumentRef.scala
@@ -0,0 +1,3 @@
+package mdr.pdb
+
+type DocumentRef = String
diff --git a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
index 4f1db43..2aaa7b8 100644
--- a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
+++ b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
@@ -6,4 +6,4 @@
 
 trait Codecs extends mdr.pdb.json.Codecs:
 
-  given JsonCodec[AutorizujDukaz] = DeriveJsonCodec.gen
+  given JsonCodec[AuthorizeProof] = DeriveJsonCodec.gen

diff --git a/build.sbt b/build.sbt
index 91b192f..a533b1e 100644
--- a/build.sbt
+++ b/build.sbt
@@ -8,6 +8,13 @@
 
 ThisBuild / scalaVersion := scala3Version
 
+lazy val proof = entityProject("proof", file("domain/proof"))
+  .components(_.dependsOn(ui))
+  .model(_.dependsOn(core))
+  .json(_.dependsOn(json))
+  .repo(_.dependsOn(`mongo-support`))
+  .endpoints(_.dependsOn(`tapir-support`))
+
 lazy val parameters = entityProject("parameters", file("domain/parameters"))
   .components(_.dependsOn(ui))
   .model(_.dependsOn(core))
@@ -55,6 +62,16 @@
   .jsSettings(IWDeps.tapirSttpClient)
   .jvmSettings(IWDeps.tapirZIO, IWDeps.tapirZIOHttp4sServer)
 
+lazy val `mongo-support` = project
+  .in(file("fiftyforms/mongo"))
+  .settings(
+    IWDeps.useZIO(Test),
+    IWDeps.zioJson,
+    IWDeps.zioConfig,
+    libraryDependencies += ("org.mongodb.scala" %% "mongo-scala-driver" % "4.2.3")
+      .cross(CrossVersion.for3Use2_13)
+  )
+
 lazy val app = (project in file("app"))
   .enablePlugins(ScalaJSPlugin, VitePlugin)
   .settings(
@@ -85,6 +102,8 @@
     parameters.command.client,
     users.query.client,
     users.command.client,
+    proof.query.client,
+    proof.command.client,
     endpoints.js
   )
 
@@ -134,6 +153,8 @@
     parameters.command.api,
     users.query.api,
     users.command.api,
+    proof.query.api,
+    proof.command.api,
     endpoints.jvm
   )
 
diff --git a/core/src/main/scala/mdr/pdb/DocumentRef.scala b/core/src/main/scala/mdr/pdb/DocumentRef.scala
new file mode 100644
index 0000000..42d4108
--- /dev/null
+++ b/core/src/main/scala/mdr/pdb/DocumentRef.scala
@@ -0,0 +1,3 @@
+package mdr.pdb
+
+type DocumentRef = String
diff --git a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
index 4f1db43..2aaa7b8 100644
--- a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
+++ b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
@@ -6,4 +6,4 @@
 
 trait Codecs extends mdr.pdb.json.Codecs:
 
-  given JsonCodec[AutorizujDukaz] = DeriveJsonCodec.gen
+  given JsonCodec[AuthorizeProof] = DeriveJsonCodec.gen
diff --git a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
index 5f0f74c..a030e98 100644
--- a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
+++ b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
@@ -7,9 +7,7 @@
 
 sealed trait Command
 
-type DocumentRef = String
-
-case class AutorizujDukaz(
+case class AuthorizeProof(
     osoba: OsobniCislo,
     parametr: Parameter.Id,
     kriterium: ParameterCriterion.Id,

diff --git a/build.sbt b/build.sbt
index 91b192f..a533b1e 100644
--- a/build.sbt
+++ b/build.sbt
@@ -8,6 +8,13 @@
 
 ThisBuild / scalaVersion := scala3Version
 
+lazy val proof = entityProject("proof", file("domain/proof"))
+  .components(_.dependsOn(ui))
+  .model(_.dependsOn(core))
+  .json(_.dependsOn(json))
+  .repo(_.dependsOn(`mongo-support`))
+  .endpoints(_.dependsOn(`tapir-support`))
+
 lazy val parameters = entityProject("parameters", file("domain/parameters"))
   .components(_.dependsOn(ui))
   .model(_.dependsOn(core))
@@ -55,6 +62,16 @@
   .jsSettings(IWDeps.tapirSttpClient)
   .jvmSettings(IWDeps.tapirZIO, IWDeps.tapirZIOHttp4sServer)
 
+lazy val `mongo-support` = project
+  .in(file("fiftyforms/mongo"))
+  .settings(
+    IWDeps.useZIO(Test),
+    IWDeps.zioJson,
+    IWDeps.zioConfig,
+    libraryDependencies += ("org.mongodb.scala" %% "mongo-scala-driver" % "4.2.3")
+      .cross(CrossVersion.for3Use2_13)
+  )
+
 lazy val app = (project in file("app"))
   .enablePlugins(ScalaJSPlugin, VitePlugin)
   .settings(
@@ -85,6 +102,8 @@
     parameters.command.client,
     users.query.client,
     users.command.client,
+    proof.query.client,
+    proof.command.client,
     endpoints.js
   )
 
@@ -134,6 +153,8 @@
     parameters.command.api,
     users.query.api,
     users.command.api,
+    proof.query.api,
+    proof.command.api,
     endpoints.jvm
   )
 
diff --git a/core/src/main/scala/mdr/pdb/DocumentRef.scala b/core/src/main/scala/mdr/pdb/DocumentRef.scala
new file mode 100644
index 0000000..42d4108
--- /dev/null
+++ b/core/src/main/scala/mdr/pdb/DocumentRef.scala
@@ -0,0 +1,3 @@
+package mdr.pdb
+
+type DocumentRef = String
diff --git a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
index 4f1db43..2aaa7b8 100644
--- a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
+++ b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
@@ -6,4 +6,4 @@
 
 trait Codecs extends mdr.pdb.json.Codecs:
 
-  given JsonCodec[AutorizujDukaz] = DeriveJsonCodec.gen
+  given JsonCodec[AuthorizeProof] = DeriveJsonCodec.gen
diff --git a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
index 5f0f74c..a030e98 100644
--- a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
+++ b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
@@ -7,9 +7,7 @@
 
 sealed trait Command
 
-type DocumentRef = String
-
-case class AutorizujDukaz(
+case class AuthorizeProof(
     osoba: OsobniCislo,
     parametr: Parameter.Id,
     kriterium: ParameterCriterion.Id,
diff --git a/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala b/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
index 07eb9a6..95df195 100644
--- a/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
+++ b/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
@@ -6,7 +6,21 @@
 
 import zio.*
 
+object ParametersRepository:
+  sealed trait Criteria:
+    type Result
+  trait MultiResultCriteria extends Criteria:
+    override type Result = List[Parameter]
+  trait SingleResultCriteria extends Criteria:
+    override type Result = Option[Parameter]
+
+  case object Any extends MultiResultCriteria
+  case class WithId(id: Parameter.Id) extends SingleResultCriteria
+  case class OfUser(osc: OsobniCislo) extends MultiResultCriteria
+
 trait ParametersRepository:
-  def allParameters(): Task[List[Parameter]]
-  def parametersOfUser(user: OsobniCislo): Task[List[Parameter]]
-  def proofsOfUser(user: OsobniCislo): Task[List[Proof]]
+  import ParametersRepository.Criteria
+  def matching(criteria: Criteria): Task[criteria.Result]
+
+private[query] trait ParametersRepositoryWrite extends ParametersRepository:
+  def put(parameter: Parameter): Task[Unit]

diff --git a/build.sbt b/build.sbt
index 91b192f..a533b1e 100644
--- a/build.sbt
+++ b/build.sbt
@@ -8,6 +8,13 @@
 
 ThisBuild / scalaVersion := scala3Version
 
+lazy val proof = entityProject("proof", file("domain/proof"))
+  .components(_.dependsOn(ui))
+  .model(_.dependsOn(core))
+  .json(_.dependsOn(json))
+  .repo(_.dependsOn(`mongo-support`))
+  .endpoints(_.dependsOn(`tapir-support`))
+
 lazy val parameters = entityProject("parameters", file("domain/parameters"))
   .components(_.dependsOn(ui))
   .model(_.dependsOn(core))
@@ -55,6 +62,16 @@
   .jsSettings(IWDeps.tapirSttpClient)
   .jvmSettings(IWDeps.tapirZIO, IWDeps.tapirZIOHttp4sServer)
 
+lazy val `mongo-support` = project
+  .in(file("fiftyforms/mongo"))
+  .settings(
+    IWDeps.useZIO(Test),
+    IWDeps.zioJson,
+    IWDeps.zioConfig,
+    libraryDependencies += ("org.mongodb.scala" %% "mongo-scala-driver" % "4.2.3")
+      .cross(CrossVersion.for3Use2_13)
+  )
+
 lazy val app = (project in file("app"))
   .enablePlugins(ScalaJSPlugin, VitePlugin)
   .settings(
@@ -85,6 +102,8 @@
     parameters.command.client,
     users.query.client,
     users.command.client,
+    proof.query.client,
+    proof.command.client,
     endpoints.js
   )
 
@@ -134,6 +153,8 @@
     parameters.command.api,
     users.query.api,
     users.command.api,
+    proof.query.api,
+    proof.command.api,
     endpoints.jvm
   )
 
diff --git a/core/src/main/scala/mdr/pdb/DocumentRef.scala b/core/src/main/scala/mdr/pdb/DocumentRef.scala
new file mode 100644
index 0000000..42d4108
--- /dev/null
+++ b/core/src/main/scala/mdr/pdb/DocumentRef.scala
@@ -0,0 +1,3 @@
+package mdr.pdb
+
+type DocumentRef = String
diff --git a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
index 4f1db43..2aaa7b8 100644
--- a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
+++ b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
@@ -6,4 +6,4 @@
 
 trait Codecs extends mdr.pdb.json.Codecs:
 
-  given JsonCodec[AutorizujDukaz] = DeriveJsonCodec.gen
+  given JsonCodec[AuthorizeProof] = DeriveJsonCodec.gen
diff --git a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
index 5f0f74c..a030e98 100644
--- a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
+++ b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
@@ -7,9 +7,7 @@
 
 sealed trait Command
 
-type DocumentRef = String
-
-case class AutorizujDukaz(
+case class AuthorizeProof(
     osoba: OsobniCislo,
     parametr: Parameter.Id,
     kriterium: ParameterCriterion.Id,
diff --git a/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala b/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
index 07eb9a6..95df195 100644
--- a/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
+++ b/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
@@ -6,7 +6,21 @@
 
 import zio.*
 
+object ParametersRepository:
+  sealed trait Criteria:
+    type Result
+  trait MultiResultCriteria extends Criteria:
+    override type Result = List[Parameter]
+  trait SingleResultCriteria extends Criteria:
+    override type Result = Option[Parameter]
+
+  case object Any extends MultiResultCriteria
+  case class WithId(id: Parameter.Id) extends SingleResultCriteria
+  case class OfUser(osc: OsobniCislo) extends MultiResultCriteria
+
 trait ParametersRepository:
-  def allParameters(): Task[List[Parameter]]
-  def parametersOfUser(user: OsobniCislo): Task[List[Parameter]]
-  def proofsOfUser(user: OsobniCislo): Task[List[Proof]]
+  import ParametersRepository.Criteria
+  def matching(criteria: Criteria): Task[criteria.Result]
+
+private[query] trait ParametersRepositoryWrite extends ParametersRepository:
+  def put(parameter: Parameter): Task[Unit]
diff --git a/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala b/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
index 04cc1d7..6cc8bf7 100644
--- a/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
+++ b/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
@@ -3,10 +3,7 @@
 
 import java.math.BigInteger
 import java.security.MessageDigest
-
-case class Proof(
-    criterionId: ParameterCriterion.Id
-)
+import java.time.LocalDate
 
 object ParameterCriterion:
   type Id = String

diff --git a/build.sbt b/build.sbt
index 91b192f..a533b1e 100644
--- a/build.sbt
+++ b/build.sbt
@@ -8,6 +8,13 @@
 
 ThisBuild / scalaVersion := scala3Version
 
+lazy val proof = entityProject("proof", file("domain/proof"))
+  .components(_.dependsOn(ui))
+  .model(_.dependsOn(core))
+  .json(_.dependsOn(json))
+  .repo(_.dependsOn(`mongo-support`))
+  .endpoints(_.dependsOn(`tapir-support`))
+
 lazy val parameters = entityProject("parameters", file("domain/parameters"))
   .components(_.dependsOn(ui))
   .model(_.dependsOn(core))
@@ -55,6 +62,16 @@
   .jsSettings(IWDeps.tapirSttpClient)
   .jvmSettings(IWDeps.tapirZIO, IWDeps.tapirZIOHttp4sServer)
 
+lazy val `mongo-support` = project
+  .in(file("fiftyforms/mongo"))
+  .settings(
+    IWDeps.useZIO(Test),
+    IWDeps.zioJson,
+    IWDeps.zioConfig,
+    libraryDependencies += ("org.mongodb.scala" %% "mongo-scala-driver" % "4.2.3")
+      .cross(CrossVersion.for3Use2_13)
+  )
+
 lazy val app = (project in file("app"))
   .enablePlugins(ScalaJSPlugin, VitePlugin)
   .settings(
@@ -85,6 +102,8 @@
     parameters.command.client,
     users.query.client,
     users.command.client,
+    proof.query.client,
+    proof.command.client,
     endpoints.js
   )
 
@@ -134,6 +153,8 @@
     parameters.command.api,
     users.query.api,
     users.command.api,
+    proof.query.api,
+    proof.command.api,
     endpoints.jvm
   )
 
diff --git a/core/src/main/scala/mdr/pdb/DocumentRef.scala b/core/src/main/scala/mdr/pdb/DocumentRef.scala
new file mode 100644
index 0000000..42d4108
--- /dev/null
+++ b/core/src/main/scala/mdr/pdb/DocumentRef.scala
@@ -0,0 +1,3 @@
+package mdr.pdb
+
+type DocumentRef = String
diff --git a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
index 4f1db43..2aaa7b8 100644
--- a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
+++ b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
@@ -6,4 +6,4 @@
 
 trait Codecs extends mdr.pdb.json.Codecs:
 
-  given JsonCodec[AutorizujDukaz] = DeriveJsonCodec.gen
+  given JsonCodec[AuthorizeProof] = DeriveJsonCodec.gen
diff --git a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
index 5f0f74c..a030e98 100644
--- a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
+++ b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
@@ -7,9 +7,7 @@
 
 sealed trait Command
 
-type DocumentRef = String
-
-case class AutorizujDukaz(
+case class AuthorizeProof(
     osoba: OsobniCislo,
     parametr: Parameter.Id,
     kriterium: ParameterCriterion.Id,
diff --git a/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala b/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
index 07eb9a6..95df195 100644
--- a/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
+++ b/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
@@ -6,7 +6,21 @@
 
 import zio.*
 
+object ParametersRepository:
+  sealed trait Criteria:
+    type Result
+  trait MultiResultCriteria extends Criteria:
+    override type Result = List[Parameter]
+  trait SingleResultCriteria extends Criteria:
+    override type Result = Option[Parameter]
+
+  case object Any extends MultiResultCriteria
+  case class WithId(id: Parameter.Id) extends SingleResultCriteria
+  case class OfUser(osc: OsobniCislo) extends MultiResultCriteria
+
 trait ParametersRepository:
-  def allParameters(): Task[List[Parameter]]
-  def parametersOfUser(user: OsobniCislo): Task[List[Parameter]]
-  def proofsOfUser(user: OsobniCislo): Task[List[Proof]]
+  import ParametersRepository.Criteria
+  def matching(criteria: Criteria): Task[criteria.Result]
+
+private[query] trait ParametersRepositoryWrite extends ParametersRepository:
+  def put(parameter: Parameter): Task[Unit]
diff --git a/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala b/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
index 04cc1d7..6cc8bf7 100644
--- a/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
+++ b/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
@@ -3,10 +3,7 @@
 
 import java.math.BigInteger
 import java.security.MessageDigest
-
-case class Proof(
-    criterionId: ParameterCriterion.Id
-)
+import java.time.LocalDate
 
 object ParameterCriterion:
   type Id = String
diff --git a/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala
new file mode 100644
index 0000000..fad055c
--- /dev/null
+++ b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala
@@ -0,0 +1,63 @@
+package mdr.pdb.proof
+package query.repo
+
+import zio.*
+import zio.json.*
+import zio.config.*
+import org.mongodb.scala.*
+import org.mongodb.scala.model.Filters.*
+import org.bson.json.JsonObject
+import fiftyforms.mongo.MongoJsonRepository
+
+case class MongoProofConfig(db: String, collection: String)
+
+object MongoProofConfig {
+  val configDesc =
+    import ConfigDescriptor.*
+    nested("MONGO")(
+      nested("PROOF")(
+        string("DB").default("mdrpdb") zip string("COLL").default("proof")
+      )
+    )
+      .to[MongoProofConfig]
+  val fromEnv: ZLayer[System, ReadError[String], MongoProofConfig] =
+    ZConfig.fromSystemEnv(configDesc)
+}
+
+object MongoProofRepository:
+  private val repo =
+    for
+      config <- ZIO.service[MongoProofConfig]
+      client <- ZIO.service[MongoClient]
+      coll <- Task.attempt {
+        client
+          .getDatabase(config.db)
+          .getCollection[JsonObject](config.collection)
+      }
+    yield MongoProofRepository(coll)
+
+  val layer: RLayer[MongoProofConfig & MongoClient, ProofRepository] =
+    repo.toLayer
+
+  private[query] val writeLayer
+      : RLayer[MongoProofConfig & MongoClient, ProofRepositoryWrite] =
+    repo.toLayer
+
+private[query] class MongoProofRepository(
+    collection: MongoCollection[JsonObject]
+) extends ProofRepositoryWrite:
+  import ProofRepository.*
+  import mdr.pdb.proof.json.Codecs.given
+
+  private val jsonRepo = MongoJsonRepository[Proof, String, Criteria](
+    collection, {
+      _ match
+        case WithId(id)    => equal("id", id)
+        case OfPerson(osc) => equal("person", osc.toString)
+    },
+    p => ("id", p.id)
+  )
+
+  export jsonRepo.matching
+
+  export jsonRepo.put

diff --git a/build.sbt b/build.sbt
index 91b192f..a533b1e 100644
--- a/build.sbt
+++ b/build.sbt
@@ -8,6 +8,13 @@
 
 ThisBuild / scalaVersion := scala3Version
 
+lazy val proof = entityProject("proof", file("domain/proof"))
+  .components(_.dependsOn(ui))
+  .model(_.dependsOn(core))
+  .json(_.dependsOn(json))
+  .repo(_.dependsOn(`mongo-support`))
+  .endpoints(_.dependsOn(`tapir-support`))
+
 lazy val parameters = entityProject("parameters", file("domain/parameters"))
   .components(_.dependsOn(ui))
   .model(_.dependsOn(core))
@@ -55,6 +62,16 @@
   .jsSettings(IWDeps.tapirSttpClient)
   .jvmSettings(IWDeps.tapirZIO, IWDeps.tapirZIOHttp4sServer)
 
+lazy val `mongo-support` = project
+  .in(file("fiftyforms/mongo"))
+  .settings(
+    IWDeps.useZIO(Test),
+    IWDeps.zioJson,
+    IWDeps.zioConfig,
+    libraryDependencies += ("org.mongodb.scala" %% "mongo-scala-driver" % "4.2.3")
+      .cross(CrossVersion.for3Use2_13)
+  )
+
 lazy val app = (project in file("app"))
   .enablePlugins(ScalaJSPlugin, VitePlugin)
   .settings(
@@ -85,6 +102,8 @@
     parameters.command.client,
     users.query.client,
     users.command.client,
+    proof.query.client,
+    proof.command.client,
     endpoints.js
   )
 
@@ -134,6 +153,8 @@
     parameters.command.api,
     users.query.api,
     users.command.api,
+    proof.query.api,
+    proof.command.api,
     endpoints.jvm
   )
 
diff --git a/core/src/main/scala/mdr/pdb/DocumentRef.scala b/core/src/main/scala/mdr/pdb/DocumentRef.scala
new file mode 100644
index 0000000..42d4108
--- /dev/null
+++ b/core/src/main/scala/mdr/pdb/DocumentRef.scala
@@ -0,0 +1,3 @@
+package mdr.pdb
+
+type DocumentRef = String
diff --git a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
index 4f1db43..2aaa7b8 100644
--- a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
+++ b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
@@ -6,4 +6,4 @@
 
 trait Codecs extends mdr.pdb.json.Codecs:
 
-  given JsonCodec[AutorizujDukaz] = DeriveJsonCodec.gen
+  given JsonCodec[AuthorizeProof] = DeriveJsonCodec.gen
diff --git a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
index 5f0f74c..a030e98 100644
--- a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
+++ b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
@@ -7,9 +7,7 @@
 
 sealed trait Command
 
-type DocumentRef = String
-
-case class AutorizujDukaz(
+case class AuthorizeProof(
     osoba: OsobniCislo,
     parametr: Parameter.Id,
     kriterium: ParameterCriterion.Id,
diff --git a/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala b/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
index 07eb9a6..95df195 100644
--- a/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
+++ b/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
@@ -6,7 +6,21 @@
 
 import zio.*
 
+object ParametersRepository:
+  sealed trait Criteria:
+    type Result
+  trait MultiResultCriteria extends Criteria:
+    override type Result = List[Parameter]
+  trait SingleResultCriteria extends Criteria:
+    override type Result = Option[Parameter]
+
+  case object Any extends MultiResultCriteria
+  case class WithId(id: Parameter.Id) extends SingleResultCriteria
+  case class OfUser(osc: OsobniCislo) extends MultiResultCriteria
+
 trait ParametersRepository:
-  def allParameters(): Task[List[Parameter]]
-  def parametersOfUser(user: OsobniCislo): Task[List[Parameter]]
-  def proofsOfUser(user: OsobniCislo): Task[List[Proof]]
+  import ParametersRepository.Criteria
+  def matching(criteria: Criteria): Task[criteria.Result]
+
+private[query] trait ParametersRepositoryWrite extends ParametersRepository:
+  def put(parameter: Parameter): Task[Unit]
diff --git a/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala b/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
index 04cc1d7..6cc8bf7 100644
--- a/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
+++ b/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
@@ -3,10 +3,7 @@
 
 import java.math.BigInteger
 import java.security.MessageDigest
-
-case class Proof(
-    criterionId: ParameterCriterion.Id
-)
+import java.time.LocalDate
 
 object ParameterCriterion:
   type Id = String
diff --git a/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala
new file mode 100644
index 0000000..fad055c
--- /dev/null
+++ b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala
@@ -0,0 +1,63 @@
+package mdr.pdb.proof
+package query.repo
+
+import zio.*
+import zio.json.*
+import zio.config.*
+import org.mongodb.scala.*
+import org.mongodb.scala.model.Filters.*
+import org.bson.json.JsonObject
+import fiftyforms.mongo.MongoJsonRepository
+
+case class MongoProofConfig(db: String, collection: String)
+
+object MongoProofConfig {
+  val configDesc =
+    import ConfigDescriptor.*
+    nested("MONGO")(
+      nested("PROOF")(
+        string("DB").default("mdrpdb") zip string("COLL").default("proof")
+      )
+    )
+      .to[MongoProofConfig]
+  val fromEnv: ZLayer[System, ReadError[String], MongoProofConfig] =
+    ZConfig.fromSystemEnv(configDesc)
+}
+
+object MongoProofRepository:
+  private val repo =
+    for
+      config <- ZIO.service[MongoProofConfig]
+      client <- ZIO.service[MongoClient]
+      coll <- Task.attempt {
+        client
+          .getDatabase(config.db)
+          .getCollection[JsonObject](config.collection)
+      }
+    yield MongoProofRepository(coll)
+
+  val layer: RLayer[MongoProofConfig & MongoClient, ProofRepository] =
+    repo.toLayer
+
+  private[query] val writeLayer
+      : RLayer[MongoProofConfig & MongoClient, ProofRepositoryWrite] =
+    repo.toLayer
+
+private[query] class MongoProofRepository(
+    collection: MongoCollection[JsonObject]
+) extends ProofRepositoryWrite:
+  import ProofRepository.*
+  import mdr.pdb.proof.json.Codecs.given
+
+  private val jsonRepo = MongoJsonRepository[Proof, String, Criteria](
+    collection, {
+      _ match
+        case WithId(id)    => equal("id", id)
+        case OfPerson(osc) => equal("person", osc.toString)
+    },
+    p => ("id", p.id)
+  )
+
+  export jsonRepo.matching
+
+  export jsonRepo.put
diff --git a/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/ProofRepository.scala b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/ProofRepository.scala
new file mode 100644
index 0000000..ae34fa2
--- /dev/null
+++ b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/ProofRepository.scala
@@ -0,0 +1,17 @@
+package mdr.pdb
+package proof
+package query.repo
+
+import zio.*
+
+object ProofRepository:
+  sealed trait Criteria
+  case class WithId(id: Proof.Id) extends Criteria
+  case class OfPerson(osc: OsobniCislo) extends Criteria
+
+trait ProofRepository:
+  import ProofRepository.*
+  def matching(criteria: Criteria): Task[Seq[Proof]]
+
+private[query] trait ProofRepositoryWrite extends ProofRepository:
+  def put(proof: Proof): Task[Unit]

diff --git a/build.sbt b/build.sbt
index 91b192f..a533b1e 100644
--- a/build.sbt
+++ b/build.sbt
@@ -8,6 +8,13 @@
 
 ThisBuild / scalaVersion := scala3Version
 
+lazy val proof = entityProject("proof", file("domain/proof"))
+  .components(_.dependsOn(ui))
+  .model(_.dependsOn(core))
+  .json(_.dependsOn(json))
+  .repo(_.dependsOn(`mongo-support`))
+  .endpoints(_.dependsOn(`tapir-support`))
+
 lazy val parameters = entityProject("parameters", file("domain/parameters"))
   .components(_.dependsOn(ui))
   .model(_.dependsOn(core))
@@ -55,6 +62,16 @@
   .jsSettings(IWDeps.tapirSttpClient)
   .jvmSettings(IWDeps.tapirZIO, IWDeps.tapirZIOHttp4sServer)
 
+lazy val `mongo-support` = project
+  .in(file("fiftyforms/mongo"))
+  .settings(
+    IWDeps.useZIO(Test),
+    IWDeps.zioJson,
+    IWDeps.zioConfig,
+    libraryDependencies += ("org.mongodb.scala" %% "mongo-scala-driver" % "4.2.3")
+      .cross(CrossVersion.for3Use2_13)
+  )
+
 lazy val app = (project in file("app"))
   .enablePlugins(ScalaJSPlugin, VitePlugin)
   .settings(
@@ -85,6 +102,8 @@
     parameters.command.client,
     users.query.client,
     users.command.client,
+    proof.query.client,
+    proof.command.client,
     endpoints.js
   )
 
@@ -134,6 +153,8 @@
     parameters.command.api,
     users.query.api,
     users.command.api,
+    proof.query.api,
+    proof.command.api,
     endpoints.jvm
   )
 
diff --git a/core/src/main/scala/mdr/pdb/DocumentRef.scala b/core/src/main/scala/mdr/pdb/DocumentRef.scala
new file mode 100644
index 0000000..42d4108
--- /dev/null
+++ b/core/src/main/scala/mdr/pdb/DocumentRef.scala
@@ -0,0 +1,3 @@
+package mdr.pdb
+
+type DocumentRef = String
diff --git a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
index 4f1db43..2aaa7b8 100644
--- a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
+++ b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
@@ -6,4 +6,4 @@
 
 trait Codecs extends mdr.pdb.json.Codecs:
 
-  given JsonCodec[AutorizujDukaz] = DeriveJsonCodec.gen
+  given JsonCodec[AuthorizeProof] = DeriveJsonCodec.gen
diff --git a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
index 5f0f74c..a030e98 100644
--- a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
+++ b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
@@ -7,9 +7,7 @@
 
 sealed trait Command
 
-type DocumentRef = String
-
-case class AutorizujDukaz(
+case class AuthorizeProof(
     osoba: OsobniCislo,
     parametr: Parameter.Id,
     kriterium: ParameterCriterion.Id,
diff --git a/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala b/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
index 07eb9a6..95df195 100644
--- a/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
+++ b/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
@@ -6,7 +6,21 @@
 
 import zio.*
 
+object ParametersRepository:
+  sealed trait Criteria:
+    type Result
+  trait MultiResultCriteria extends Criteria:
+    override type Result = List[Parameter]
+  trait SingleResultCriteria extends Criteria:
+    override type Result = Option[Parameter]
+
+  case object Any extends MultiResultCriteria
+  case class WithId(id: Parameter.Id) extends SingleResultCriteria
+  case class OfUser(osc: OsobniCislo) extends MultiResultCriteria
+
 trait ParametersRepository:
-  def allParameters(): Task[List[Parameter]]
-  def parametersOfUser(user: OsobniCislo): Task[List[Parameter]]
-  def proofsOfUser(user: OsobniCislo): Task[List[Proof]]
+  import ParametersRepository.Criteria
+  def matching(criteria: Criteria): Task[criteria.Result]
+
+private[query] trait ParametersRepositoryWrite extends ParametersRepository:
+  def put(parameter: Parameter): Task[Unit]
diff --git a/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala b/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
index 04cc1d7..6cc8bf7 100644
--- a/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
+++ b/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
@@ -3,10 +3,7 @@
 
 import java.math.BigInteger
 import java.security.MessageDigest
-
-case class Proof(
-    criterionId: ParameterCriterion.Id
-)
+import java.time.LocalDate
 
 object ParameterCriterion:
   type Id = String
diff --git a/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala
new file mode 100644
index 0000000..fad055c
--- /dev/null
+++ b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala
@@ -0,0 +1,63 @@
+package mdr.pdb.proof
+package query.repo
+
+import zio.*
+import zio.json.*
+import zio.config.*
+import org.mongodb.scala.*
+import org.mongodb.scala.model.Filters.*
+import org.bson.json.JsonObject
+import fiftyforms.mongo.MongoJsonRepository
+
+case class MongoProofConfig(db: String, collection: String)
+
+object MongoProofConfig {
+  val configDesc =
+    import ConfigDescriptor.*
+    nested("MONGO")(
+      nested("PROOF")(
+        string("DB").default("mdrpdb") zip string("COLL").default("proof")
+      )
+    )
+      .to[MongoProofConfig]
+  val fromEnv: ZLayer[System, ReadError[String], MongoProofConfig] =
+    ZConfig.fromSystemEnv(configDesc)
+}
+
+object MongoProofRepository:
+  private val repo =
+    for
+      config <- ZIO.service[MongoProofConfig]
+      client <- ZIO.service[MongoClient]
+      coll <- Task.attempt {
+        client
+          .getDatabase(config.db)
+          .getCollection[JsonObject](config.collection)
+      }
+    yield MongoProofRepository(coll)
+
+  val layer: RLayer[MongoProofConfig & MongoClient, ProofRepository] =
+    repo.toLayer
+
+  private[query] val writeLayer
+      : RLayer[MongoProofConfig & MongoClient, ProofRepositoryWrite] =
+    repo.toLayer
+
+private[query] class MongoProofRepository(
+    collection: MongoCollection[JsonObject]
+) extends ProofRepositoryWrite:
+  import ProofRepository.*
+  import mdr.pdb.proof.json.Codecs.given
+
+  private val jsonRepo = MongoJsonRepository[Proof, String, Criteria](
+    collection, {
+      _ match
+        case WithId(id)    => equal("id", id)
+        case OfPerson(osc) => equal("person", osc.toString)
+    },
+    p => ("id", p.id)
+  )
+
+  export jsonRepo.matching
+
+  export jsonRepo.put
diff --git a/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/ProofRepository.scala b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/ProofRepository.scala
new file mode 100644
index 0000000..ae34fa2
--- /dev/null
+++ b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/ProofRepository.scala
@@ -0,0 +1,17 @@
+package mdr.pdb
+package proof
+package query.repo
+
+import zio.*
+
+object ProofRepository:
+  sealed trait Criteria
+  case class WithId(id: Proof.Id) extends Criteria
+  case class OfPerson(osc: OsobniCislo) extends Criteria
+
+trait ProofRepository:
+  import ProofRepository.*
+  def matching(criteria: Criteria): Task[Seq[Proof]]
+
+private[query] trait ProofRepositoryWrite extends ProofRepository:
+  def put(proof: Proof): Task[Unit]
diff --git a/domain/proof/shared/json/src/main/scala/mdr/pdb/proof/json/Codecs.scala b/domain/proof/shared/json/src/main/scala/mdr/pdb/proof/json/Codecs.scala
new file mode 100644
index 0000000..bef8a2b
--- /dev/null
+++ b/domain/proof/shared/json/src/main/scala/mdr/pdb/proof/json/Codecs.scala
@@ -0,0 +1,12 @@
+package mdr.pdb.proof
+package json
+
+import zio.json.*
+
+trait Codecs extends mdr.pdb.json.Codecs:
+
+  given JsonCodec[Authorization] = DeriveJsonCodec.gen
+  given JsonCodec[Revocation] = DeriveJsonCodec.gen
+  given JsonCodec[Proof] = DeriveJsonCodec.gen
+
+object Codecs extends Codecs

diff --git a/build.sbt b/build.sbt
index 91b192f..a533b1e 100644
--- a/build.sbt
+++ b/build.sbt
@@ -8,6 +8,13 @@
 
 ThisBuild / scalaVersion := scala3Version
 
+lazy val proof = entityProject("proof", file("domain/proof"))
+  .components(_.dependsOn(ui))
+  .model(_.dependsOn(core))
+  .json(_.dependsOn(json))
+  .repo(_.dependsOn(`mongo-support`))
+  .endpoints(_.dependsOn(`tapir-support`))
+
 lazy val parameters = entityProject("parameters", file("domain/parameters"))
   .components(_.dependsOn(ui))
   .model(_.dependsOn(core))
@@ -55,6 +62,16 @@
   .jsSettings(IWDeps.tapirSttpClient)
   .jvmSettings(IWDeps.tapirZIO, IWDeps.tapirZIOHttp4sServer)
 
+lazy val `mongo-support` = project
+  .in(file("fiftyforms/mongo"))
+  .settings(
+    IWDeps.useZIO(Test),
+    IWDeps.zioJson,
+    IWDeps.zioConfig,
+    libraryDependencies += ("org.mongodb.scala" %% "mongo-scala-driver" % "4.2.3")
+      .cross(CrossVersion.for3Use2_13)
+  )
+
 lazy val app = (project in file("app"))
   .enablePlugins(ScalaJSPlugin, VitePlugin)
   .settings(
@@ -85,6 +102,8 @@
     parameters.command.client,
     users.query.client,
     users.command.client,
+    proof.query.client,
+    proof.command.client,
     endpoints.js
   )
 
@@ -134,6 +153,8 @@
     parameters.command.api,
     users.query.api,
     users.command.api,
+    proof.query.api,
+    proof.command.api,
     endpoints.jvm
   )
 
diff --git a/core/src/main/scala/mdr/pdb/DocumentRef.scala b/core/src/main/scala/mdr/pdb/DocumentRef.scala
new file mode 100644
index 0000000..42d4108
--- /dev/null
+++ b/core/src/main/scala/mdr/pdb/DocumentRef.scala
@@ -0,0 +1,3 @@
+package mdr.pdb
+
+type DocumentRef = String
diff --git a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
index 4f1db43..2aaa7b8 100644
--- a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
+++ b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
@@ -6,4 +6,4 @@
 
 trait Codecs extends mdr.pdb.json.Codecs:
 
-  given JsonCodec[AutorizujDukaz] = DeriveJsonCodec.gen
+  given JsonCodec[AuthorizeProof] = DeriveJsonCodec.gen
diff --git a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
index 5f0f74c..a030e98 100644
--- a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
+++ b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
@@ -7,9 +7,7 @@
 
 sealed trait Command
 
-type DocumentRef = String
-
-case class AutorizujDukaz(
+case class AuthorizeProof(
     osoba: OsobniCislo,
     parametr: Parameter.Id,
     kriterium: ParameterCriterion.Id,
diff --git a/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala b/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
index 07eb9a6..95df195 100644
--- a/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
+++ b/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
@@ -6,7 +6,21 @@
 
 import zio.*
 
+object ParametersRepository:
+  sealed trait Criteria:
+    type Result
+  trait MultiResultCriteria extends Criteria:
+    override type Result = List[Parameter]
+  trait SingleResultCriteria extends Criteria:
+    override type Result = Option[Parameter]
+
+  case object Any extends MultiResultCriteria
+  case class WithId(id: Parameter.Id) extends SingleResultCriteria
+  case class OfUser(osc: OsobniCislo) extends MultiResultCriteria
+
 trait ParametersRepository:
-  def allParameters(): Task[List[Parameter]]
-  def parametersOfUser(user: OsobniCislo): Task[List[Parameter]]
-  def proofsOfUser(user: OsobniCislo): Task[List[Proof]]
+  import ParametersRepository.Criteria
+  def matching(criteria: Criteria): Task[criteria.Result]
+
+private[query] trait ParametersRepositoryWrite extends ParametersRepository:
+  def put(parameter: Parameter): Task[Unit]
diff --git a/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala b/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
index 04cc1d7..6cc8bf7 100644
--- a/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
+++ b/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
@@ -3,10 +3,7 @@
 
 import java.math.BigInteger
 import java.security.MessageDigest
-
-case class Proof(
-    criterionId: ParameterCriterion.Id
-)
+import java.time.LocalDate
 
 object ParameterCriterion:
   type Id = String
diff --git a/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala
new file mode 100644
index 0000000..fad055c
--- /dev/null
+++ b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala
@@ -0,0 +1,63 @@
+package mdr.pdb.proof
+package query.repo
+
+import zio.*
+import zio.json.*
+import zio.config.*
+import org.mongodb.scala.*
+import org.mongodb.scala.model.Filters.*
+import org.bson.json.JsonObject
+import fiftyforms.mongo.MongoJsonRepository
+
+case class MongoProofConfig(db: String, collection: String)
+
+object MongoProofConfig {
+  val configDesc =
+    import ConfigDescriptor.*
+    nested("MONGO")(
+      nested("PROOF")(
+        string("DB").default("mdrpdb") zip string("COLL").default("proof")
+      )
+    )
+      .to[MongoProofConfig]
+  val fromEnv: ZLayer[System, ReadError[String], MongoProofConfig] =
+    ZConfig.fromSystemEnv(configDesc)
+}
+
+object MongoProofRepository:
+  private val repo =
+    for
+      config <- ZIO.service[MongoProofConfig]
+      client <- ZIO.service[MongoClient]
+      coll <- Task.attempt {
+        client
+          .getDatabase(config.db)
+          .getCollection[JsonObject](config.collection)
+      }
+    yield MongoProofRepository(coll)
+
+  val layer: RLayer[MongoProofConfig & MongoClient, ProofRepository] =
+    repo.toLayer
+
+  private[query] val writeLayer
+      : RLayer[MongoProofConfig & MongoClient, ProofRepositoryWrite] =
+    repo.toLayer
+
+private[query] class MongoProofRepository(
+    collection: MongoCollection[JsonObject]
+) extends ProofRepositoryWrite:
+  import ProofRepository.*
+  import mdr.pdb.proof.json.Codecs.given
+
+  private val jsonRepo = MongoJsonRepository[Proof, String, Criteria](
+    collection, {
+      _ match
+        case WithId(id)    => equal("id", id)
+        case OfPerson(osc) => equal("person", osc.toString)
+    },
+    p => ("id", p.id)
+  )
+
+  export jsonRepo.matching
+
+  export jsonRepo.put
diff --git a/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/ProofRepository.scala b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/ProofRepository.scala
new file mode 100644
index 0000000..ae34fa2
--- /dev/null
+++ b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/ProofRepository.scala
@@ -0,0 +1,17 @@
+package mdr.pdb
+package proof
+package query.repo
+
+import zio.*
+
+object ProofRepository:
+  sealed trait Criteria
+  case class WithId(id: Proof.Id) extends Criteria
+  case class OfPerson(osc: OsobniCislo) extends Criteria
+
+trait ProofRepository:
+  import ProofRepository.*
+  def matching(criteria: Criteria): Task[Seq[Proof]]
+
+private[query] trait ProofRepositoryWrite extends ProofRepository:
+  def put(proof: Proof): Task[Unit]
diff --git a/domain/proof/shared/json/src/main/scala/mdr/pdb/proof/json/Codecs.scala b/domain/proof/shared/json/src/main/scala/mdr/pdb/proof/json/Codecs.scala
new file mode 100644
index 0000000..bef8a2b
--- /dev/null
+++ b/domain/proof/shared/json/src/main/scala/mdr/pdb/proof/json/Codecs.scala
@@ -0,0 +1,12 @@
+package mdr.pdb.proof
+package json
+
+import zio.json.*
+
+trait Codecs extends mdr.pdb.json.Codecs:
+
+  given JsonCodec[Authorization] = DeriveJsonCodec.gen
+  given JsonCodec[Revocation] = DeriveJsonCodec.gen
+  given JsonCodec[Proof] = DeriveJsonCodec.gen
+
+object Codecs extends Codecs
diff --git a/domain/proof/shared/model/src/main/scala/mdr/pdb/proof/Proof.scala b/domain/proof/shared/model/src/main/scala/mdr/pdb/proof/Proof.scala
new file mode 100644
index 0000000..7052edc
--- /dev/null
+++ b/domain/proof/shared/model/src/main/scala/mdr/pdb/proof/Proof.scala
@@ -0,0 +1,32 @@
+package mdr.pdb
+package proof
+
+import java.time.Instant
+import java.time.LocalDate
+
+case class Authorization(
+    time: Instant,
+    person: OsobniCislo
+)
+
+case class Revocation(
+    time: Instant,
+    person: OsobniCislo,
+    explanation: String,
+    documents: List[DocumentRef]
+)
+
+case class Proof(
+    person: OsobniCislo,
+    id: Proof.Id,
+    parameterId: String,
+    criterionId: String,
+    documents: List[DocumentRef],
+    note: String,
+    authorizations: List[Authorization],
+    expiration: Option[LocalDate],
+    revocation: Option[Revocation]
+)
+
+object Proof:
+  type Id = String

diff --git a/build.sbt b/build.sbt
index 91b192f..a533b1e 100644
--- a/build.sbt
+++ b/build.sbt
@@ -8,6 +8,13 @@
 
 ThisBuild / scalaVersion := scala3Version
 
+lazy val proof = entityProject("proof", file("domain/proof"))
+  .components(_.dependsOn(ui))
+  .model(_.dependsOn(core))
+  .json(_.dependsOn(json))
+  .repo(_.dependsOn(`mongo-support`))
+  .endpoints(_.dependsOn(`tapir-support`))
+
 lazy val parameters = entityProject("parameters", file("domain/parameters"))
   .components(_.dependsOn(ui))
   .model(_.dependsOn(core))
@@ -55,6 +62,16 @@
   .jsSettings(IWDeps.tapirSttpClient)
   .jvmSettings(IWDeps.tapirZIO, IWDeps.tapirZIOHttp4sServer)
 
+lazy val `mongo-support` = project
+  .in(file("fiftyforms/mongo"))
+  .settings(
+    IWDeps.useZIO(Test),
+    IWDeps.zioJson,
+    IWDeps.zioConfig,
+    libraryDependencies += ("org.mongodb.scala" %% "mongo-scala-driver" % "4.2.3")
+      .cross(CrossVersion.for3Use2_13)
+  )
+
 lazy val app = (project in file("app"))
   .enablePlugins(ScalaJSPlugin, VitePlugin)
   .settings(
@@ -85,6 +102,8 @@
     parameters.command.client,
     users.query.client,
     users.command.client,
+    proof.query.client,
+    proof.command.client,
     endpoints.js
   )
 
@@ -134,6 +153,8 @@
     parameters.command.api,
     users.query.api,
     users.command.api,
+    proof.query.api,
+    proof.command.api,
     endpoints.jvm
   )
 
diff --git a/core/src/main/scala/mdr/pdb/DocumentRef.scala b/core/src/main/scala/mdr/pdb/DocumentRef.scala
new file mode 100644
index 0000000..42d4108
--- /dev/null
+++ b/core/src/main/scala/mdr/pdb/DocumentRef.scala
@@ -0,0 +1,3 @@
+package mdr.pdb
+
+type DocumentRef = String
diff --git a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
index 4f1db43..2aaa7b8 100644
--- a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
+++ b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
@@ -6,4 +6,4 @@
 
 trait Codecs extends mdr.pdb.json.Codecs:
 
-  given JsonCodec[AutorizujDukaz] = DeriveJsonCodec.gen
+  given JsonCodec[AuthorizeProof] = DeriveJsonCodec.gen
diff --git a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
index 5f0f74c..a030e98 100644
--- a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
+++ b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
@@ -7,9 +7,7 @@
 
 sealed trait Command
 
-type DocumentRef = String
-
-case class AutorizujDukaz(
+case class AuthorizeProof(
     osoba: OsobniCislo,
     parametr: Parameter.Id,
     kriterium: ParameterCriterion.Id,
diff --git a/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala b/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
index 07eb9a6..95df195 100644
--- a/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
+++ b/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
@@ -6,7 +6,21 @@
 
 import zio.*
 
+object ParametersRepository:
+  sealed trait Criteria:
+    type Result
+  trait MultiResultCriteria extends Criteria:
+    override type Result = List[Parameter]
+  trait SingleResultCriteria extends Criteria:
+    override type Result = Option[Parameter]
+
+  case object Any extends MultiResultCriteria
+  case class WithId(id: Parameter.Id) extends SingleResultCriteria
+  case class OfUser(osc: OsobniCislo) extends MultiResultCriteria
+
 trait ParametersRepository:
-  def allParameters(): Task[List[Parameter]]
-  def parametersOfUser(user: OsobniCislo): Task[List[Parameter]]
-  def proofsOfUser(user: OsobniCislo): Task[List[Proof]]
+  import ParametersRepository.Criteria
+  def matching(criteria: Criteria): Task[criteria.Result]
+
+private[query] trait ParametersRepositoryWrite extends ParametersRepository:
+  def put(parameter: Parameter): Task[Unit]
diff --git a/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala b/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
index 04cc1d7..6cc8bf7 100644
--- a/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
+++ b/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
@@ -3,10 +3,7 @@
 
 import java.math.BigInteger
 import java.security.MessageDigest
-
-case class Proof(
-    criterionId: ParameterCriterion.Id
-)
+import java.time.LocalDate
 
 object ParameterCriterion:
   type Id = String
diff --git a/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala
new file mode 100644
index 0000000..fad055c
--- /dev/null
+++ b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala
@@ -0,0 +1,63 @@
+package mdr.pdb.proof
+package query.repo
+
+import zio.*
+import zio.json.*
+import zio.config.*
+import org.mongodb.scala.*
+import org.mongodb.scala.model.Filters.*
+import org.bson.json.JsonObject
+import fiftyforms.mongo.MongoJsonRepository
+
+case class MongoProofConfig(db: String, collection: String)
+
+object MongoProofConfig {
+  val configDesc =
+    import ConfigDescriptor.*
+    nested("MONGO")(
+      nested("PROOF")(
+        string("DB").default("mdrpdb") zip string("COLL").default("proof")
+      )
+    )
+      .to[MongoProofConfig]
+  val fromEnv: ZLayer[System, ReadError[String], MongoProofConfig] =
+    ZConfig.fromSystemEnv(configDesc)
+}
+
+object MongoProofRepository:
+  private val repo =
+    for
+      config <- ZIO.service[MongoProofConfig]
+      client <- ZIO.service[MongoClient]
+      coll <- Task.attempt {
+        client
+          .getDatabase(config.db)
+          .getCollection[JsonObject](config.collection)
+      }
+    yield MongoProofRepository(coll)
+
+  val layer: RLayer[MongoProofConfig & MongoClient, ProofRepository] =
+    repo.toLayer
+
+  private[query] val writeLayer
+      : RLayer[MongoProofConfig & MongoClient, ProofRepositoryWrite] =
+    repo.toLayer
+
+private[query] class MongoProofRepository(
+    collection: MongoCollection[JsonObject]
+) extends ProofRepositoryWrite:
+  import ProofRepository.*
+  import mdr.pdb.proof.json.Codecs.given
+
+  private val jsonRepo = MongoJsonRepository[Proof, String, Criteria](
+    collection, {
+      _ match
+        case WithId(id)    => equal("id", id)
+        case OfPerson(osc) => equal("person", osc.toString)
+    },
+    p => ("id", p.id)
+  )
+
+  export jsonRepo.matching
+
+  export jsonRepo.put
diff --git a/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/ProofRepository.scala b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/ProofRepository.scala
new file mode 100644
index 0000000..ae34fa2
--- /dev/null
+++ b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/ProofRepository.scala
@@ -0,0 +1,17 @@
+package mdr.pdb
+package proof
+package query.repo
+
+import zio.*
+
+object ProofRepository:
+  sealed trait Criteria
+  case class WithId(id: Proof.Id) extends Criteria
+  case class OfPerson(osc: OsobniCislo) extends Criteria
+
+trait ProofRepository:
+  import ProofRepository.*
+  def matching(criteria: Criteria): Task[Seq[Proof]]
+
+private[query] trait ProofRepositoryWrite extends ProofRepository:
+  def put(proof: Proof): Task[Unit]
diff --git a/domain/proof/shared/json/src/main/scala/mdr/pdb/proof/json/Codecs.scala b/domain/proof/shared/json/src/main/scala/mdr/pdb/proof/json/Codecs.scala
new file mode 100644
index 0000000..bef8a2b
--- /dev/null
+++ b/domain/proof/shared/json/src/main/scala/mdr/pdb/proof/json/Codecs.scala
@@ -0,0 +1,12 @@
+package mdr.pdb.proof
+package json
+
+import zio.json.*
+
+trait Codecs extends mdr.pdb.json.Codecs:
+
+  given JsonCodec[Authorization] = DeriveJsonCodec.gen
+  given JsonCodec[Revocation] = DeriveJsonCodec.gen
+  given JsonCodec[Proof] = DeriveJsonCodec.gen
+
+object Codecs extends Codecs
diff --git a/domain/proof/shared/model/src/main/scala/mdr/pdb/proof/Proof.scala b/domain/proof/shared/model/src/main/scala/mdr/pdb/proof/Proof.scala
new file mode 100644
index 0000000..7052edc
--- /dev/null
+++ b/domain/proof/shared/model/src/main/scala/mdr/pdb/proof/Proof.scala
@@ -0,0 +1,32 @@
+package mdr.pdb
+package proof
+
+import java.time.Instant
+import java.time.LocalDate
+
+case class Authorization(
+    time: Instant,
+    person: OsobniCislo
+)
+
+case class Revocation(
+    time: Instant,
+    person: OsobniCislo,
+    explanation: String,
+    documents: List[DocumentRef]
+)
+
+case class Proof(
+    person: OsobniCislo,
+    id: Proof.Id,
+    parameterId: String,
+    criterionId: String,
+    documents: List[DocumentRef],
+    note: String,
+    authorizations: List[Authorization],
+    expiration: Option[LocalDate],
+    revocation: Option[Revocation]
+)
+
+object Proof:
+  type Id = String
diff --git a/fiftyforms/mongo/src/main/scala/fiftyforms/mongo/MongoJsonRepository.scala b/fiftyforms/mongo/src/main/scala/fiftyforms/mongo/MongoJsonRepository.scala
new file mode 100644
index 0000000..eff2357
--- /dev/null
+++ b/fiftyforms/mongo/src/main/scala/fiftyforms/mongo/MongoJsonRepository.scala
@@ -0,0 +1,53 @@
+package fiftyforms.mongo
+
+import zio.*
+import zio.json.*
+import zio.config.*
+import org.mongodb.scala.*
+import org.mongodb.scala.model.Filters.*
+import org.bson.json.JsonObject
+import org.mongodb.scala.model.ReplaceOptions
+import org.mongodb.scala.bson.conversions.Bson
+
+case class MongoConfig(uri: String)
+
+object MongoConfig:
+  val configDesc =
+    import ConfigDescriptor.*
+    nested("MONGO")(string("URI").default("mongodb://localhost:27017"))
+      .to[MongoConfig]
+  val fromEnv = ZConfig.fromSystemEnv(configDesc)
+
+val client: RLayer[MongoConfig, MongoClient] =
+  (for
+    config <- ZIO.service[MongoConfig]
+    client <- Task.attempt(MongoClient(config.uri))
+  yield client).toLayer
+
+class MongoJsonRepository[Elem, Key, Criteria](
+    collection: MongoCollection[JsonObject],
+    toFilter: Criteria => Bson,
+    idFilter: Elem => (String, Key)
+)(using JsonCodec[Elem]) {
+  def matching(criteria: Criteria): Task[Seq[Elem]] =
+    val filter = toFilter(criteria)
+    val query = collection.find(filter)
+
+    for
+      result <- ZIO.fromFuture(_ => query.toFuture)
+      proof <- ZIO.collect(result)(j =>
+        ZIO.fromOption(j.getJson.fromJson[Elem].toOption)
+      )
+    yield proof
+
+  def put(elem: Elem): Task[Unit] =
+    Task.async(cb =>
+      collection
+        .replaceOne(
+          equal.tupled(idFilter(elem)),
+          JsonObject(elem.toJson),
+          ReplaceOptions().upsert(true)
+        )
+        .subscribe(_ => cb(Task.unit), t => cb(Task.fail(t)))
+    )
+}

diff --git a/build.sbt b/build.sbt
index 91b192f..a533b1e 100644
--- a/build.sbt
+++ b/build.sbt
@@ -8,6 +8,13 @@
 
 ThisBuild / scalaVersion := scala3Version
 
+lazy val proof = entityProject("proof", file("domain/proof"))
+  .components(_.dependsOn(ui))
+  .model(_.dependsOn(core))
+  .json(_.dependsOn(json))
+  .repo(_.dependsOn(`mongo-support`))
+  .endpoints(_.dependsOn(`tapir-support`))
+
 lazy val parameters = entityProject("parameters", file("domain/parameters"))
   .components(_.dependsOn(ui))
   .model(_.dependsOn(core))
@@ -55,6 +62,16 @@
   .jsSettings(IWDeps.tapirSttpClient)
   .jvmSettings(IWDeps.tapirZIO, IWDeps.tapirZIOHttp4sServer)
 
+lazy val `mongo-support` = project
+  .in(file("fiftyforms/mongo"))
+  .settings(
+    IWDeps.useZIO(Test),
+    IWDeps.zioJson,
+    IWDeps.zioConfig,
+    libraryDependencies += ("org.mongodb.scala" %% "mongo-scala-driver" % "4.2.3")
+      .cross(CrossVersion.for3Use2_13)
+  )
+
 lazy val app = (project in file("app"))
   .enablePlugins(ScalaJSPlugin, VitePlugin)
   .settings(
@@ -85,6 +102,8 @@
     parameters.command.client,
     users.query.client,
     users.command.client,
+    proof.query.client,
+    proof.command.client,
     endpoints.js
   )
 
@@ -134,6 +153,8 @@
     parameters.command.api,
     users.query.api,
     users.command.api,
+    proof.query.api,
+    proof.command.api,
     endpoints.jvm
   )
 
diff --git a/core/src/main/scala/mdr/pdb/DocumentRef.scala b/core/src/main/scala/mdr/pdb/DocumentRef.scala
new file mode 100644
index 0000000..42d4108
--- /dev/null
+++ b/core/src/main/scala/mdr/pdb/DocumentRef.scala
@@ -0,0 +1,3 @@
+package mdr.pdb
+
+type DocumentRef = String
diff --git a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
index 4f1db43..2aaa7b8 100644
--- a/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
+++ b/domain/parameters/command/json/src/main/scala/mdr/pdb/parameters/command/Codecs.scala
@@ -6,4 +6,4 @@
 
 trait Codecs extends mdr.pdb.json.Codecs:
 
-  given JsonCodec[AutorizujDukaz] = DeriveJsonCodec.gen
+  given JsonCodec[AuthorizeProof] = DeriveJsonCodec.gen
diff --git a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
index 5f0f74c..a030e98 100644
--- a/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
+++ b/domain/parameters/command/model/src/main/scala/mdr/pdb/parameters/command/commands.scala
@@ -7,9 +7,7 @@
 
 sealed trait Command
 
-type DocumentRef = String
-
-case class AutorizujDukaz(
+case class AuthorizeProof(
     osoba: OsobniCislo,
     parametr: Parameter.Id,
     kriterium: ParameterCriterion.Id,
diff --git a/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala b/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
index 07eb9a6..95df195 100644
--- a/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
+++ b/domain/parameters/query/repo/src/main/scala/mdr/pdb/parameters/query/repo/ParametersRepository.scala
@@ -6,7 +6,21 @@
 
 import zio.*
 
+object ParametersRepository:
+  sealed trait Criteria:
+    type Result
+  trait MultiResultCriteria extends Criteria:
+    override type Result = List[Parameter]
+  trait SingleResultCriteria extends Criteria:
+    override type Result = Option[Parameter]
+
+  case object Any extends MultiResultCriteria
+  case class WithId(id: Parameter.Id) extends SingleResultCriteria
+  case class OfUser(osc: OsobniCislo) extends MultiResultCriteria
+
 trait ParametersRepository:
-  def allParameters(): Task[List[Parameter]]
-  def parametersOfUser(user: OsobniCislo): Task[List[Parameter]]
-  def proofsOfUser(user: OsobniCislo): Task[List[Proof]]
+  import ParametersRepository.Criteria
+  def matching(criteria: Criteria): Task[criteria.Result]
+
+private[query] trait ParametersRepositoryWrite extends ParametersRepository:
+  def put(parameter: Parameter): Task[Unit]
diff --git a/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala b/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
index 04cc1d7..6cc8bf7 100644
--- a/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
+++ b/domain/parameters/shared/model/src/main/scala/mdr/pdb/parameters/Parameter.scala
@@ -3,10 +3,7 @@
 
 import java.math.BigInteger
 import java.security.MessageDigest
-
-case class Proof(
-    criterionId: ParameterCriterion.Id
-)
+import java.time.LocalDate
 
 object ParameterCriterion:
   type Id = String
diff --git a/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala
new file mode 100644
index 0000000..fad055c
--- /dev/null
+++ b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/MongoProofRepository.scala
@@ -0,0 +1,63 @@
+package mdr.pdb.proof
+package query.repo
+
+import zio.*
+import zio.json.*
+import zio.config.*
+import org.mongodb.scala.*
+import org.mongodb.scala.model.Filters.*
+import org.bson.json.JsonObject
+import fiftyforms.mongo.MongoJsonRepository
+
+case class MongoProofConfig(db: String, collection: String)
+
+object MongoProofConfig {
+  val configDesc =
+    import ConfigDescriptor.*
+    nested("MONGO")(
+      nested("PROOF")(
+        string("DB").default("mdrpdb") zip string("COLL").default("proof")
+      )
+    )
+      .to[MongoProofConfig]
+  val fromEnv: ZLayer[System, ReadError[String], MongoProofConfig] =
+    ZConfig.fromSystemEnv(configDesc)
+}
+
+object MongoProofRepository:
+  private val repo =
+    for
+      config <- ZIO.service[MongoProofConfig]
+      client <- ZIO.service[MongoClient]
+      coll <- Task.attempt {
+        client
+          .getDatabase(config.db)
+          .getCollection[JsonObject](config.collection)
+      }
+    yield MongoProofRepository(coll)
+
+  val layer: RLayer[MongoProofConfig & MongoClient, ProofRepository] =
+    repo.toLayer
+
+  private[query] val writeLayer
+      : RLayer[MongoProofConfig & MongoClient, ProofRepositoryWrite] =
+    repo.toLayer
+
+private[query] class MongoProofRepository(
+    collection: MongoCollection[JsonObject]
+) extends ProofRepositoryWrite:
+  import ProofRepository.*
+  import mdr.pdb.proof.json.Codecs.given
+
+  private val jsonRepo = MongoJsonRepository[Proof, String, Criteria](
+    collection, {
+      _ match
+        case WithId(id)    => equal("id", id)
+        case OfPerson(osc) => equal("person", osc.toString)
+    },
+    p => ("id", p.id)
+  )
+
+  export jsonRepo.matching
+
+  export jsonRepo.put
diff --git a/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/ProofRepository.scala b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/ProofRepository.scala
new file mode 100644
index 0000000..ae34fa2
--- /dev/null
+++ b/domain/proof/query/repo/src/main/scala/mdr/pdb/query/repo/ProofRepository.scala
@@ -0,0 +1,17 @@
+package mdr.pdb
+package proof
+package query.repo
+
+import zio.*
+
+object ProofRepository:
+  sealed trait Criteria
+  case class WithId(id: Proof.Id) extends Criteria
+  case class OfPerson(osc: OsobniCislo) extends Criteria
+
+trait ProofRepository:
+  import ProofRepository.*
+  def matching(criteria: Criteria): Task[Seq[Proof]]
+
+private[query] trait ProofRepositoryWrite extends ProofRepository:
+  def put(proof: Proof): Task[Unit]
diff --git a/domain/proof/shared/json/src/main/scala/mdr/pdb/proof/json/Codecs.scala b/domain/proof/shared/json/src/main/scala/mdr/pdb/proof/json/Codecs.scala
new file mode 100644
index 0000000..bef8a2b
--- /dev/null
+++ b/domain/proof/shared/json/src/main/scala/mdr/pdb/proof/json/Codecs.scala
@@ -0,0 +1,12 @@
+package mdr.pdb.proof
+package json
+
+import zio.json.*
+
+trait Codecs extends mdr.pdb.json.Codecs:
+
+  given JsonCodec[Authorization] = DeriveJsonCodec.gen
+  given JsonCodec[Revocation] = DeriveJsonCodec.gen
+  given JsonCodec[Proof] = DeriveJsonCodec.gen
+
+object Codecs extends Codecs
diff --git a/domain/proof/shared/model/src/main/scala/mdr/pdb/proof/Proof.scala b/domain/proof/shared/model/src/main/scala/mdr/pdb/proof/Proof.scala
new file mode 100644
index 0000000..7052edc
--- /dev/null
+++ b/domain/proof/shared/model/src/main/scala/mdr/pdb/proof/Proof.scala
@@ -0,0 +1,32 @@
+package mdr.pdb
+package proof
+
+import java.time.Instant
+import java.time.LocalDate
+
+case class Authorization(
+    time: Instant,
+    person: OsobniCislo
+)
+
+case class Revocation(
+    time: Instant,
+    person: OsobniCislo,
+    explanation: String,
+    documents: List[DocumentRef]
+)
+
+case class Proof(
+    person: OsobniCislo,
+    id: Proof.Id,
+    parameterId: String,
+    criterionId: String,
+    documents: List[DocumentRef],
+    note: String,
+    authorizations: List[Authorization],
+    expiration: Option[LocalDate],
+    revocation: Option[Revocation]
+)
+
+object Proof:
+  type Id = String
diff --git a/fiftyforms/mongo/src/main/scala/fiftyforms/mongo/MongoJsonRepository.scala b/fiftyforms/mongo/src/main/scala/fiftyforms/mongo/MongoJsonRepository.scala
new file mode 100644
index 0000000..eff2357
--- /dev/null
+++ b/fiftyforms/mongo/src/main/scala/fiftyforms/mongo/MongoJsonRepository.scala
@@ -0,0 +1,53 @@
+package fiftyforms.mongo
+
+import zio.*
+import zio.json.*
+import zio.config.*
+import org.mongodb.scala.*
+import org.mongodb.scala.model.Filters.*
+import org.bson.json.JsonObject
+import org.mongodb.scala.model.ReplaceOptions
+import org.mongodb.scala.bson.conversions.Bson
+
+case class MongoConfig(uri: String)
+
+object MongoConfig:
+  val configDesc =
+    import ConfigDescriptor.*
+    nested("MONGO")(string("URI").default("mongodb://localhost:27017"))
+      .to[MongoConfig]
+  val fromEnv = ZConfig.fromSystemEnv(configDesc)
+
+val client: RLayer[MongoConfig, MongoClient] =
+  (for
+    config <- ZIO.service[MongoConfig]
+    client <- Task.attempt(MongoClient(config.uri))
+  yield client).toLayer
+
+class MongoJsonRepository[Elem, Key, Criteria](
+    collection: MongoCollection[JsonObject],
+    toFilter: Criteria => Bson,
+    idFilter: Elem => (String, Key)
+)(using JsonCodec[Elem]) {
+  def matching(criteria: Criteria): Task[Seq[Elem]] =
+    val filter = toFilter(criteria)
+    val query = collection.find(filter)
+
+    for
+      result <- ZIO.fromFuture(_ => query.toFuture)
+      proof <- ZIO.collect(result)(j =>
+        ZIO.fromOption(j.getJson.fromJson[Elem].toOption)
+      )
+    yield proof
+
+  def put(elem: Elem): Task[Unit] =
+    Task.async(cb =>
+      collection
+        .replaceOne(
+          equal.tupled(idFilter(elem)),
+          JsonObject(elem.toJson),
+          ReplaceOptions().upsert(true)
+        )
+        .subscribe(_ => cb(Task.unit), t => cb(Task.fail(t)))
+    )
+}
diff --git a/project/DomainProjectsPlugin.scala b/project/DomainProjectsPlugin.scala
index b52edb1..6aad728 100644
--- a/project/DomainProjectsPlugin.scala
+++ b/project/DomainProjectsPlugin.scala
@@ -37,6 +37,7 @@
       query(_.endpoints(upd)).command(_.endpoints(upd))
     def components(upd: Project => Project): EntityProject =
       query(_.components(upd)).command(_.components(upd))
+    def repo(upd: Project => Project): EntityProject = query(_.repo(upd))
     override def componentProjects: Seq[Project] =
       Seq(model, json).flatMap(
         _.componentProjects