diff --git a/backend/src/ada-holder/ada-holder.controller.ts b/backend/src/ada-holder/ada-holder.controller.ts
new file mode 100644
index 0000000..0ff7d56
--- /dev/null
+++ b/backend/src/ada-holder/ada-holder.controller.ts
@@ -0,0 +1,23 @@
+import { Controller, Get, Query } from '@nestjs/common';
+import { ApiOperation, ApiQuery, ApiTags } from '@nestjs/swagger';
+import { AdaHolderService } from './ada-holder.service';
+
+@ApiTags('ada-holder')
+@Controller('ada-holder')
+export class AdaHolderController {
+  constructor(private adaHolderService: AdaHolderService) {}
+
+  @Get('get-current-delegation/:stakeKey')
+  @ApiOperation({ summary: 'Get current delegation of a stake key' })
+  @ApiQuery({ name: 'stakeKey', type: 'string', required: true })
+  async getCurrentDelegation(@Query('stakeKey') stakeKey: string) {
+    return this.adaHolderService.getCurrentDelegation(stakeKey);
+  }
+
+  @Get('get-voting-power/:stakeKey')
+  @ApiOperation({ summary: 'Get voting power of a stake key' })
+  @ApiQuery({ name: 'stakeKey', type: 'string', required: true })
+  async getVotingPower(@Query('stakeKey') stakeKey: string) {
+    return this.adaHolderService.getVotingPower(stakeKey);
+  }
+}
diff --git a/backend/src/ada-holder/ada-holder.module.ts b/backend/src/ada-holder/ada-holder.module.ts
new file mode 100644
index 0000000..db1f41c
--- /dev/null
+++ b/backend/src/ada-holder/ada-holder.module.ts
@@ -0,0 +1,9 @@
+import { Module } from '@nestjs/common';
+import { AdaHolderController } from './ada-holder.controller';
+import { AdaHolderService } from './ada-holder.service';
+
+@Module({
+  controllers: [AdaHolderController],
+  providers: [AdaHolderService],
+})
+export class AdaHolderModule {}
diff --git a/backend/src/ada-holder/ada-holder.service.ts b/backend/src/ada-holder/ada-holder.service.ts
new file mode 100644
index 0000000..d37f6a2
--- /dev/null
+++ b/backend/src/ada-holder/ada-holder.service.ts
@@ -0,0 +1,63 @@
+import { Injectable } from '@nestjs/common';
+import { InjectDataSource } from '@nestjs/typeorm';
+import path from 'path';
+import * as fs from 'fs';
+import { DataSource } from 'typeorm';
+
+@Injectable()
+export class AdaHolderService {
+  constructor(
+    @InjectDataSource()
+    private readonly dataSource: DataSource,
+  ) {}
+
+  async getCurrentDelegation(stakeKey: string) {
+    try {
+      const sqlFilePath = path.join(
+        __dirname,
+        '../sql',
+        'get-current-delegation.sql',
+      );
+      const sql = fs.readFileSync(sqlFilePath, 'utf8');
+
+      const result = await this.dataSource.query(sql, [stakeKey]);
+      if (result.length === 0) {
+        return null;
+      }
+
+      const [mDRepHash, dRepView, txHash] = result[0];
+
+      return {
+        dRepHash: mDRepHash,
+        dRepView,
+        txHash,
+      };
+    } catch (error) {
+      console.error(error);
+      return null;
+    }
+  }
+
+  async getVotingPower(stakeKey: string) {
+    console.log('stakeKey', stakeKey);
+    try {
+      const sqlFilePath = path.join(
+        __dirname,
+        '../sql',
+        'get-voting-power.sql',
+      );
+      const sql = fs.readFileSync(sqlFilePath, 'utf8');
+
+      const result = await this.dataSource.query(sql, [stakeKey]);
+
+      if (result.length === 0) {
+        return 0;
+      }
+
+      return result[0];
+    } catch (error) {
+      console.error(error);
+      return null;
+    }
+  }
+}
diff --git a/backend/src/app.module.ts b/backend/src/app.module.ts
index 58e3425..2ac2c42 100644
--- a/backend/src/app.module.ts
+++ b/backend/src/app.module.ts
@@ -3,6 +3,8 @@ import { ConfigModule, ConfigService } from '@nestjs/config';
 import { TypeOrmModule } from '@nestjs/typeorm';
 
 import { ProposalModule } from './proposal/proposal.module';
+import { AdaHolderModule } from './ada-holder/ada-holder.module';
+import { DrepModule } from './drep/drep.module';
 
 @Module({
   imports: [
@@ -30,6 +32,8 @@ import { ProposalModule } from './proposal/proposal.module';
       }),
     }),
     ProposalModule,
+    AdaHolderModule,
+    DrepModule,
   ],
   controllers: [],
   providers: [],
diff --git a/backend/src/drep/drep.controller.ts b/backend/src/drep/drep.controller.ts
new file mode 100644
index 0000000..f53929a
--- /dev/null
+++ b/backend/src/drep/drep.controller.ts
@@ -0,0 +1,16 @@
+import { Controller, Get, Query } from '@nestjs/common';
+import { ApiOperation, ApiQuery, ApiTags } from '@nestjs/swagger';
+import { DrepService } from './drep.service';
+
+@ApiTags('drep')
+@Controller('drep')
+export class DrepController {
+  constructor(private drepService: DrepService) {}
+
+  @Get('get-voting-power/:drepId')
+  @ApiOperation({ summary: 'Get voting power of a drep id' })
+  @ApiQuery({ name: 'drepId', type: 'string', required: true })
+  async getVotingPower(@Query('drepId') drepId: string) {
+    return this.drepService.getVotingPower(drepId);
+  }
+}
diff --git a/backend/src/drep/drep.module.ts b/backend/src/drep/drep.module.ts
new file mode 100644
index 0000000..214714c
--- /dev/null
+++ b/backend/src/drep/drep.module.ts
@@ -0,0 +1,9 @@
+import { Module } from '@nestjs/common';
+import { DrepController } from './drep.controller';
+import { DrepService } from './drep.service';
+
+@Module({
+  controllers: [DrepController],
+  providers: [DrepService],
+})
+export class DrepModule {}
diff --git a/backend/src/drep/drep.service.ts b/backend/src/drep/drep.service.ts
new file mode 100644
index 0000000..f86f186
--- /dev/null
+++ b/backend/src/drep/drep.service.ts
@@ -0,0 +1,35 @@
+import { Injectable } from '@nestjs/common';
+import { InjectDataSource } from '@nestjs/typeorm';
+import path from 'path';
+import * as fs from 'fs';
+import { DataSource } from 'typeorm';
+
+@Injectable()
+export class DrepService {
+  constructor(
+    @InjectDataSource()
+    private readonly dataSource: DataSource,
+  ) {}
+
+  async getVotingPower(drepId: string) {
+    try {
+      const sqlFilePath = path.join(
+        __dirname,
+        '../sql',
+        'get-voting-power.sql',
+      );
+      const sql = fs.readFileSync(sqlFilePath, 'utf8');
+
+      const result = await this.dataSource.query(sql, [drepId]);
+
+      if (result.length === 0) {
+        return 0;
+      }
+
+      return result[0];
+    } catch (error) {
+      console.error(error);
+      return null;
+    }
+  }
+}
diff --git a/backend/src/sql/get-current-delegation.sql b/backend/src/sql/get-current-delegation.sql
new file mode 100644
index 0000000..8373fbf
--- /dev/null
+++ b/backend/src/sql/get-current-delegation.sql
@@ -0,0 +1,19 @@
+SELECT
+  CASE
+    WHEN drep_hash.raw IS NULL THEN NULL
+    ELSE encode(drep_hash.raw, 'hex')
+  END AS drep_raw,
+  drep_hash.view AS drep_view,
+  encode(tx.hash, 'hex')
+FROM delegation_vote
+JOIN tx ON tx.id = delegation_vote.tx_id
+JOIN drep_hash ON drep_hash.id = delegation_vote.drep_hash_id
+JOIN stake_address ON stake_address.id = delegation_vote.addr_id
+WHERE stake_address.hash_raw = decode($1, 'hex')
+  AND NOT EXISTS (
+    SELECT *
+    FROM delegation_vote AS dv2
+    WHERE dv2.addr_id = delegation_vote.addr_id
+      AND dv2.tx_id > delegation_vote.tx_id
+  )
+LIMIT 1;
diff --git a/backend/src/sql/get-votes.sql b/backend/src/sql/get-votes.sql
new file mode 100644
index 0000000..6d5e5de
--- /dev/null
+++ b/backend/src/sql/get-votes.sql
@@ -0,0 +1,19 @@
+SELECT DISTINCT ON (voting_procedure.gov_action_proposal_id, voting_procedure.drep_voter)
+  voting_procedure.gov_action_proposal_id,
+  CONCAT(encode(gov_action_tx.hash, 'hex'), '#', gov_action_proposal.index),
+  encode(drep_hash.raw, 'hex'),
+  voting_procedure.vote::text,
+  voting_anchor.url,
+  encode(voting_anchor.data_hash, 'hex'),
+  block.epoch_no AS epoch_no,
+  block.time AS time,
+  encode(vote_tx.hash, 'hex') AS vote_tx_hash
+FROM voting_procedure
+JOIN gov_action_proposal ON gov_action_proposal.id = voting_procedure.gov_action_proposal_id
+JOIN drep_hash ON drep_hash.id = voting_procedure.drep_voter
+LEFT JOIN voting_anchor ON voting_anchor.id = voting_procedure.voting_anchor_id
+JOIN tx AS gov_action_tx ON gov_action_tx.id = gov_action_proposal.tx_id
+JOIN tx AS vote_tx ON vote_tx.id = voting_procedure.tx_id
+JOIN block ON block.id = vote_tx.block_id
+WHERE drep_hash.raw = decode($1, 'hex')
+ORDER BY voting_procedure.gov_action_proposal_id, voting_procedure.drep_voter, voting_procedure.id DESC
diff --git a/backend/src/sql/get-voting-power.sql b/backend/src/sql/get-voting-power.sql
new file mode 100644
index 0000000..d36d43f
--- /dev/null
+++ b/backend/src/sql/get-voting-power.sql
@@ -0,0 +1,6 @@
+SELECT COALESCE(drep_distr.amount, 0) AS amount
+FROM drep_hash
+LEFT JOIN drep_distr ON drep_hash.id = drep_distr.hash_id
+WHERE drep_hash.raw = DECODE($1::text, 'hex')
+ORDER BY epoch_no DESC
+LIMIT 1;