diff --git a/config/seeds.js b/config/seeds.js
index 0d519b7..6547537 100644
--- a/config/seeds.js
+++ b/config/seeds.js
@@ -1,16 +1,18 @@
 const contractCalls = [
   ['Contributor', 'add', [{ account: '0x7e8f313c56f809188313aa274fa67ee58c31515d', name: 'bumi', kind: 'person', url: '', github_username: 'bumi', github_uid: 318, wiki_username: 'bumi' }, { gasLimit: 200000 }]],
   ['Contributor', 'add', [{ account: '0x49575f3DD9a0d60aE661BC992f72D837A77f05Bc', name: 'raucao', kind: 'person', url: '', github_username: 'skddc', github_uid: 842, wiki_username: 'raucau' }, { gasLimit: 200000 }]],
-  ['Proposal', 'addProposal', [{ contributorId: 1, amount: 500, kind: 'code', description: '[67P/kredits-contracts] Ran the seeds', url: '' }, { gasLimit: 350000 }]],
-  ['Proposal', 'addProposal', [{ contributorId: 2, amount: 500, kind: 'code', description: '[67P/kredits-contracts] Ran the seeds', url: '' }, { gasLimit: 350000 }]],
-  ['Proposal', 'addProposal', [{ contributorId: 2, amount: 500, kind: 'code', description: '[67P/kredits-contracts] Hacked on kredits', url: '' }, { gasLimit: 350000 }]],
+  ['Proposal', 'addProposal', [{ contributorId: 1, contributorIpfsHash: 'QmWKCYGr2rSf6abUPaTYqf98urvoZxGrb7dbspFZA6oyVF', date: '2019-04-09', amount: 500, kind: 'dev', description: '[67P/kredits-contracts] Ran the seeds', url: '' }, { gasLimit: 350000 }]],
+  ['Proposal', 'addProposal', [{ contributorId: 2, contributorIpfsHash: 'QmcHzEeAM26HV2zHTf5HnZrCtCtGdEccL5kUtDakAB7ozB', date: '2019-04-10', amount: 500, kind: 'dev', description: '[67P/kredits-contracts] Ran the seeds', url: '' }, { gasLimit: 350000 }]],
+  ['Proposal', 'addProposal', [{ contributorId: 2, contributorIpfsHash: 'QmcHzEeAM26HV2zHTf5HnZrCtCtGdEccL5kUtDakAB7ozB', date: '2019-04-11', amount: 500, kind: 'dev', description: '[67P/kredits-contracts] Hacked on kredits', url: '' }, { gasLimit: 350000 }]],
   ['Proposal', 'vote', [1, { gasLimit: 550000 }]],
   ['Contribution', 'addContribution', [{ contributorId: 1, contributorIpfsHash: 'QmWKCYGr2rSf6abUPaTYqf98urvoZxGrb7dbspFZA6oyVF', date: '2019-04-11', amount: 5000, kind: 'dev', description: '[67P/kredits-contracts] Introduce contribution token', url: '' }, { gasLimit: 350000 }]],
   ['Contribution', 'addContribution', [{ contributorId: 2, contributorIpfsHash: 'QmcHzEeAM26HV2zHTf5HnZrCtCtGdEccL5kUtDakAB7ozB', date: '2019-04-11', amount: 1500, kind: 'dev', description: '[67P/kredits-web] Reviewed stuff', url: '' }, { gasLimit: 350000 }]],
   ['Contribution', 'claim', [1, { gasLimit: 300000 }]]
 ];
+
 const funds = [
   '0x7e8f313c56f809188313aa274fa67ee58c31515d',
   '0xa502eb4021f3b9ab62f75b57a94e1cfbf81fd827'
 ];
+
 module.exports = { contractCalls, funds };
diff --git a/lib/contracts/proposal.js b/lib/contracts/proposal.js
index 896b72f..5266144 100644
--- a/lib/contracts/proposal.js
+++ b/lib/contracts/proposal.js
@@ -25,12 +25,16 @@ class Proposal extends Base {
       });
   }
 
-  addProposal(proposalAttr, callOptions = {}) {
-    let json = ContributionSerializer.serialize(proposalAttr);
-    // TODO: validate against schema
+  async addProposal(proposalAttr, callOptions = {}) {
+    const contribution = new ContributionSerializer(proposalAttr);
+
+    try { await contribution.validate(); }
+    catch (error) { return Promise.reject(error); }
+
+    const jsonStr = contribution.serialize();
 
     return this.ipfs
-      .add(json)
+      .add(jsonStr)
       .then((ipfsHashAttr) => {
         let proposal = [
           proposalAttr.contributorId,
diff --git a/scripts/add-proposal.js b/scripts/add-proposal.js
index 935b461..c99fecf 100644
--- a/scripts/add-proposal.js
+++ b/scripts/add-proposal.js
@@ -1,4 +1,5 @@
 const promptly = require('promptly');
+const { inspect } = require('util');
 
 const initKredits = require('./helpers/init_kredits.js');
 
@@ -25,23 +26,31 @@ module.exports = async function(callback) {
   }
   console.log(`Creating a proposal for contributor ID #${contributorId} account: ${contributorAccount}`);
 
+  [ dateNow, timeNow ] = (new Date()).toISOString().split('T');
+
   let contributionAttributes = {
     contributorId,
+    date: dateNow,
+    time: timeNow,
     amount: await promptly.prompt('Amount: '),
     description: await promptly.prompt('Description: '),
     kind: await promptly.prompt('Kind: ', { default: 'dev' }),
     url: await promptly.prompt('URL: ', { default: '' })
   }
 
+  const contributorData = await kredits.Contributor.getById(contributorId);
+  contributionAttributes.contributorIpfsHash = contributorData.ipfsHash;
+
   console.log("\nAdding proposal:");
   console.log(contributionAttributes);
 
-  kredits.Proposal.addProposal(contributionAttributes, { gasLimit: 300000 }).then((result) => {
-    console.log("\n\nResult:");
-    console.log(result);
-    callback();
-  }).catch((error) => {
-    console.log('Failed to create proposal');
-    callback(error);
-  });
+  kredits.Proposal.addProposal(contributionAttributes, { gasLimit: 300000 })
+    .then((result) => {
+      console.log("\n\nResult:");
+      console.log(result);
+      callback();
+    }).catch((error) => {
+      console.log('Failed to create proposal');
+      callback(inspect(error));
+    });
 }