diff --git a/src/app/contract/contractParser.js b/src/app/contract/contractParser.js
new file mode 100644
index 0000000000..c9c74ab542
--- /dev/null
+++ b/src/app/contract/contractParser.js
@@ -0,0 +1,148 @@
+'use strict'
+
+var $ = require('jquery')
+var txHelper = require('../execution/txHelper')
+
+module.exports = (contractName, contract, compiledSource) => {
+  return getDetails(contractName, contract, compiledSource)
+}
+
+var getDetails = function (contractName, contract, source) {
+  var detail = {}
+  detail.name = contractName
+  detail.metadata = contract.metadata
+  if (contract.bytecode) {
+    detail.bytecode = contract.bytecode
+  }
+
+  detail.interface = contract.interface
+
+  if (contract.bytecode) {
+    detail.bytecode = contract.bytecode
+    detail.web3Deploy = gethDeploy(contractName.toLowerCase(), contract['interface'], contract.bytecode)
+
+    detail.metadataHash = retrieveMetadataHash(contract.bytecode)
+    if (detail.metadataHash) {
+      detail.swarmLocation = 'bzz://' + detail.metadataHash
+    }
+  }
+
+  detail.functionHashes = {}
+  for (var fun in contract.functionHashes) {
+    detail.functionHashes[contract.functionHashes[fun]] = fun
+  }
+
+  detail.gasEstimates = formatGasEstimates(contract.gasEstimates)
+
+  if (contract.runtimeBytecode && contract.runtimeBytecode.length > 0) {
+    detail['Runtime Bytecode'] = contract.runtimeBytecode
+  }
+
+  if (contract.opcodes !== undefined && contract.opcodes !== '') {
+    detail['Opcodes'] = contract.opcodes
+  }
+
+  if (contract.assembly !== null) {
+    detail['Assembly'] = formatAssemblyText(contract.assembly, '', source)
+  }
+
+  return detail
+}
+
+var retrieveMetadataHash = function (bytecode) {
+  var match = /a165627a7a72305820([0-9a-f]{64})0029$/.exec(bytecode)
+  if (match) {
+    return match[1]
+  }
+}
+
+var formatAssemblyText = function (asm, prefix, source) {
+  if (typeof asm === typeof '' || asm === null || asm === undefined) {
+    return prefix + asm + '\n'
+  }
+  var text = prefix + '.code\n'
+  $.each(asm['.code'], function (i, item) {
+    var v = item.value === undefined ? '' : item.value
+    var src = ''
+    if (item.begin !== undefined && item.end !== undefined) {
+      src = source.slice(item.begin, item.end).replace('\n', '\\n', 'g')
+    }
+    if (src.length > 30) {
+      src = src.slice(0, 30) + '...'
+    }
+    if (item.name !== 'tag') {
+      text += '  '
+    }
+    text += prefix + item.name + ' ' + v + '\t\t\t' + src + '\n'
+  })
+  text += prefix + '.data\n'
+  if (asm['.data']) {
+    $.each(asm['.data'], function (i, item) {
+      text += '  ' + prefix + '' + i + ':\n'
+      text += formatAssemblyText(item, prefix + '    ', source)
+    })
+  }
+  return text
+}
+
+var gethDeploy = function (contractName, jsonInterface, bytecode) {
+  var code = ''
+  var funABI = txHelper.getConstructorInterface(JSON.parse(jsonInterface))
+
+  funABI.inputs.forEach(function (inp) {
+    code += 'var ' + inp.name + ' = /* var of type ' + inp.type + ' here */ ;\n'
+  })
+
+  contractName = contractName.replace(/[:./]/g, '_')
+  code += 'var ' + contractName + 'Contract = web3.eth.contract(' + jsonInterface.replace('\n', '') + ');' +
+    '\nvar ' + contractName + ' = ' + contractName + 'Contract.new('
+
+  funABI.inputs.forEach(function (inp) {
+    code += '\n   ' + inp.name + ','
+  })
+
+  code += '\n   {' +
+    '\n     from: web3.eth.accounts[0], ' +
+    "\n     data: '0x" + bytecode + "', " +
+    "\n     gas: '4700000'" +
+    '\n   }, function (e, contract){' +
+    '\n    console.log(e, contract);' +
+    "\n    if (typeof contract.address !== 'undefined') {" +
+    "\n         console.log('Contract mined! address: ' + contract.address + ' transactionHash: ' + contract.transactionHash);" +
+    '\n    }' +
+    '\n })'
+
+  return code
+}
+
+var formatGasEstimates = function (data) {
+  // FIXME: the whole gasEstimates object should be nil instead
+  if (data.creation === undefined && data.external === undefined && data.internal === undefined) {
+    return
+  }
+
+  var gasToText = function (g) {
+    return g === null ? 'unknown' : g
+  }
+
+  var ret = {}
+  var fun
+  if ('creation' in data) {
+    ret['Creation'] = gasToText(data.creation[0]) + ' + ' + gasToText(data.creation[1]) + '\n'
+  }
+
+  if ('external' in data) {
+    ret['External'] = {}
+    for (fun in data.external) {
+      ret['External'][fun] = gasToText(data.external[fun])
+    }
+  }
+
+  if ('internal' in data) {
+    ret['Internal'] = {}
+    for (fun in data.internal) {
+      ret['Internal'][fun] = gasToText(data.internal[fun])
+    }
+  }
+  return ret
+}
diff --git a/src/app/contract/publishOnSwarm.js b/src/app/contract/publishOnSwarm.js
new file mode 100644
index 0000000000..fb10b99a53
--- /dev/null
+++ b/src/app/contract/publishOnSwarm.js
@@ -0,0 +1,65 @@
+'use strict'
+
+var async = require('async')
+var swarmgw = require('swarmgw')
+
+module.exports = (contract, appAPI, cb) => {
+  // gather list of files to publish
+  var sources = []
+
+  sources.push({
+    content: contract.metadata,
+    hash: contract.metadataHash
+  })
+
+  var metadata
+  try {
+    metadata = JSON.parse(contract.metadata)
+  } catch (e) {
+    return cb(e)
+  }
+
+  if (metadata === undefined) {
+    return cb('No metadata')
+  }
+
+  async.eachSeries(Object.keys(metadata.sources), function (fileName, cb) {
+    // find hash
+    var hash
+    try {
+      hash = metadata.sources[fileName].urls[0].match('bzzr://(.+)')[1]
+    } catch (e) {
+      return cb('Metadata inconsistency')
+    }
+
+    appAPI.fileProviderOf(fileName).get(fileName, (error, content) => {
+      if (error) {
+        console.log(error)
+      } else {
+        sources.push({
+          content: content,
+          hash: hash
+        })
+      }
+      cb()
+    })
+  }, function () {
+    // publish the list of sources in order, fail if any failed
+    async.eachSeries(sources, function (item, cb) {
+      swarmVerifiedPublish(item.content, item.hash, cb)
+    }, cb)
+  })
+}
+
+
+function swarmVerifiedPublish (content, expectedHash, cb) {
+  swarmgw.put(content, function (err, ret) {
+    if (err) {
+      cb(err)
+    } else if (ret !== expectedHash) {
+      cb('Hash mismatch')
+    } else {
+      cb()
+    }
+  })
+}
diff --git a/src/app/contract/txExecution.js b/src/app/contract/txExecution.js
new file mode 100644
index 0000000000..29515216e0
--- /dev/null
+++ b/src/app/contract/txExecution.js
@@ -0,0 +1,33 @@
+'use strict'
+
+module.exports = {
+  /**
+    * deploy the given contract
+    *
+    * @param {String} data    - data to send with the transaction ( return of txFormat.buildData(...) ).
+    * @param {Object} udap    - udapp.
+    * @param {Function} callback    - callback.
+    */
+  createContract: function (data, udapp, callback) {
+    udapp.runTx({data: data, useCall: false}, (error, txResult) => {
+      // see universaldapp.js line 660 => 700 to check possible values of txResult (error case)
+      callback(error, txResult)
+    })
+  },
+
+  /**
+    * call the current given contract
+    *
+    * @param {String} to    - address of the contract to call.
+    * @param {String} data    - data to send with the transaction ( return of txFormat.buildData(...) ).
+    * @param {Object} funAbi    - abi definition of the function to call.
+    * @param {Object} udap    - udapp.
+    * @param {Function} callback    - callback.
+    */
+  callFunction: function (to, data, funAbi, udapp, callback) {
+    udapp.runTx({to: to, data: data, useCall: funAbi.constant}, (error, txResult) => {
+      // see universaldapp.js line 660 => 700 to check possible values of txResult (error case)
+      callback(error, txResult)
+    })
+  }
+}
\ No newline at end of file
diff --git a/src/app/contract/txFormat.js b/src/app/contract/txFormat.js
new file mode 100644
index 0000000000..bc5e71cec5
--- /dev/null
+++ b/src/app/contract/txFormat.js
@@ -0,0 +1,153 @@
+'use strict'
+var $ = require('jquery')
+var ethJSABI = require('ethereumjs-abi')
+var helper = require('./txHelper')
+
+module.exports = {
+  /**
+    * build the transaction data
+    *
+    * @param {Object} contract    - abi definition of the current contract.
+    * @param {Object} contracts    - map of all compiled contracts.
+    * @param {Bool} isConstructor    - isConstructor.
+    * @param {Object} funAbi    - abi definition of the function to call. null if building data for the ctor.
+    * @param {Object} params    - input paramater of the function to call
+    * @param {Object} udapp    - udapp
+    * @param {Object} executionContext    - executionContext
+    * @param {Function} callback    - callback
+    */
+  buildData: function (contract, contracts, isConstructor, funAbi, params, udapp, executionContext, callback) {
+    var funArgs = ''
+    try {
+      funArgs = $.parseJSON('[' + params + ']')
+    } catch (e) {
+      callback('Error encoding arguments: ' + e)
+      return
+    }
+    var data = ''
+    var dataHex = ''
+    if (!isConstructor || funArgs.length > 0) {
+      try {
+        data = helper.encodeParams(funAbi, funArgs)
+        dataHex = data.toString('hex')
+      } catch (e) {
+        callback('Error encoding arguments: ' + e)
+        return
+      }
+    }
+    if (data.slice(0, 9) === 'undefined') {
+      dataHex = data.slice(9)
+    }
+    if (data.slice(0, 2) === '0x') {
+      dataHex = data.slice(2)
+    }
+    if (isConstructor) {
+      var bytecodeToDeploy = contract.bytecode
+      if (bytecodeToDeploy.indexOf('_') >= 0) {
+        this.linkBytecode(contract, contracts, executionContext, udapp, (err, bytecode) => {
+          if (err) {
+            callback('Error deploying required libraries: ' + err)
+          } else {
+            bytecodeToDeploy = bytecode + dataHex
+            return callback(null, bytecodeToDeploy)
+          }
+        })
+        return
+      } else {
+        dataHex = bytecodeToDeploy + dataHex
+      }
+    } else {
+      dataHex = Buffer.concat([helper.encodeFunctionId(funAbi), data]).toString('hex')
+    }
+    callback(null, dataHex)
+  },
+
+  atAddress: function () {},
+
+  linkBytecode: function (contract, contracts, executionContext, udapp, callback) {
+    var bytecode = contract.bytecode
+    if (bytecode.indexOf('_') < 0) {
+      return callback(null, bytecode)
+    }
+    var m = bytecode.match(/__([^_]{1,36})__/)
+    if (!m) {
+      return callback('Invalid bytecode format.')
+    }
+    var libraryName = m[1]
+    var libraryabi = helper.getContractByName(libraryName, contracts)
+    if (!libraryabi) {
+      return callback('Library ' + libraryName + ' not found.')
+    }
+    this.deployLibrary(libraryabi, executionContext, udapp, (err, address) => {
+      if (err) {
+        return callback(err)
+      }
+      var libLabel = '__' + libraryName + Array(39 - libraryName.length).join('_')
+      var hexAddress = address.toString('hex')
+      if (hexAddress.slice(0, 2) === '0x') {
+        hexAddress = hexAddress.slice(2)
+      }
+      hexAddress = Array(40 - hexAddress.length + 1).join('0') + hexAddress
+      while (bytecode.indexOf(libLabel) >= 0) {
+        bytecode = bytecode.replace(libLabel, hexAddress)
+      }
+      contract.bytecode = bytecode
+      this.linkBytecode(contract, contracts, executionContext, udapp, callback)
+    })
+  },
+
+  deployLibrary: function (libraryName, library, executionContext, udapp, callback) {
+    var address = library.address
+    if (address) {
+      return callback(null, address)
+    }
+    var bytecode = library.bytecode
+    if (bytecode.indexOf('_') >= 0) {
+      this.linkBytecode(libraryName, (err, bytecode) => {
+        if (err) callback(err)
+        else this.deployLibrary(libraryName, callback)
+      })
+    } else {
+      udapp.runTx({ data: bytecode, useCall: false }, (err, txResult) => {
+        if (err) {
+          return callback(err)
+        }
+        var address = executionContext.isVM() ? txResult.result.createdAddress : txResult.result.contractAddress
+        library.address = address
+        callback(err, address)
+      })
+    }
+  },
+
+  decodeResponse: function (response, fnabi, callback) {
+    // Only decode if there supposed to be fields
+    if (fnabi.outputs && fnabi.outputs.length > 0) {
+      try {
+        var i
+
+        var outputTypes = []
+        for (i = 0; i < fnabi.outputs.length; i++) {
+          outputTypes.push(fnabi.outputs[i].type)
+        }
+
+        // decode data
+        var decodedObj = ethJSABI.rawDecode(outputTypes, response)
+
+        // format decoded data
+        decodedObj = ethJSABI.stringify(outputTypes, decodedObj)
+        for (i = 0; i < outputTypes.length; i++) {
+          var name = fnabi.outputs[i].name
+          if (name.length > 0) {
+            decodedObj[i] = outputTypes[i] + ' ' + name + ': ' + decodedObj[i]
+          } else {
+            decodedObj[i] = outputTypes[i] + ': ' + decodedObj[i]
+          }
+        }
+
+        return callback(null, decodedObj)
+      } catch (e) {
+        return callback('Failed to decode output: ' + e)
+      }
+    }
+  }
+}
diff --git a/src/app/contract/txHelper.js b/src/app/contract/txHelper.js
new file mode 100644
index 0000000000..ee0bc46904
--- /dev/null
+++ b/src/app/contract/txHelper.js
@@ -0,0 +1,106 @@
+'use strict'
+var ethJSABI = require('ethereumjs-abi')
+var $ = require('jquery')
+
+module.exports = {
+  encodeParams: function (funABI, args) {
+    var types = []
+    if (funABI.inputs && funABI.inputs.length) {
+      for (var i = 0; i < funABI.inputs.length; i++) {
+        types.push(funABI.inputs[i].type)
+      }
+    }
+
+    // NOTE: the caller will concatenate the bytecode and this
+    //       it could be done here too for consistency
+    return ethJSABI.rawEncode(types, args)
+  },
+
+  encodeFunctionId: function (funABI) {
+    var types = []
+    if (funABI.inputs && funABI.inputs.length) {
+      for (var i = 0; i < funABI.inputs.length; i++) {
+        types.push(funABI.inputs[i].type)
+      }
+    }
+
+    return ethJSABI.methodID(funABI.name, types)
+  },
+
+  sortAbiFunction: function (contract) {
+    var abi = JSON.parse(contract.interface).sort(function (a, b) {
+      if (a.name > b.name) {
+        return -1
+      } else {
+        return 1
+      }
+    }).sort(function (a, b) {
+      if (a.constant === true) {
+        return -1
+      } else {
+        return 1
+      }
+    })
+    return abi
+  },
+
+  getConstructorInterface: function (abi) {
+    var funABI = { 'name': '', 'inputs': [], 'type': 'constructor', 'outputs': [] }
+    if (typeof abi === 'string') {
+      try {
+        abi = JSON.parse(abi)
+      } catch (e) {
+        console.log('exception retrieving ctor abi ' + abi)
+        return funABI
+      }
+    }
+
+    for (var i = 0; i < abi.length; i++) {
+      if (abi[i].type === 'constructor') {
+        funABI.inputs = abi[i].inputs || []
+        break
+      }
+    }
+
+    return funABI
+  },
+
+  getFunction: function (abi, fnName) {
+    for (var i = 0; i < abi.length; i++) {
+      if (abi[i].name === fnName) {
+        return abi[i]
+      }
+    }
+    return null
+  },
+
+  getFallbackInterface: function (abi) {
+    for (var i = 0; i < abi.length; i++) {
+      if (abi[i].type === 'fallback') {
+        return abi[i]
+      }
+    }
+  },
+
+  getContractByName: function (contractName, contracts) {
+    for (var c in contracts) {
+      if (contracts[c].name === contractName) {
+        return contracts[c]
+      }
+    }
+    return null
+  },
+
+  inputParametersDeclarationToString: function (abiinputs) {
+    var inputs = ''
+    if (abiinputs) {
+      $.each(abiinputs, function (i, inp) {
+        if (inputs !== '') {
+          inputs += ', '
+        }
+        inputs += inp.type + ' ' + inp.name
+      })
+    }
+    return inputs
+  }
+}