diff --git a/cli.js b/cli.js
index 698a80e..7e06a8b 100755
--- a/cli.js
+++ b/cli.js
@@ -38,11 +38,13 @@ const printR1cs = require("./src/printr1cs");
 
 const clProcessor = require("./src/clprocessor");
 
-const powersOfTaw = require("./src/powersoftaw");
+const powersOfTaw = require("./src/powersoftau");
 
 const bn128 = require("ffjavascript").bn128;
 const solidityGenerator = require("./src/soliditygenerator.js");
 
+const phase2 = require("./src/phase2");
+
 const commands = [
     {
         cmd: "r1cs info [circuit.r1cs]",
@@ -103,62 +105,69 @@ const commands = [
         action: solidityGenCall
     },
     {
-        cmd: "powersoftaw new <power> [powersoftaw_0000.ptaw]",
-        description: "Starts a powers of taw ceremony",
+        cmd: "powersoftau new <power> [powersoftau_0000.ptau]",
+        description: "Starts a powers of tau ceremony",
         alias: ["ptn"],
         options: "-verbose|v",
         action: powersOfTawNew
     },
     {
-        cmd: "powersoftaw export challange <powersoftaw_0000.ptaw> [challange]",
+        cmd: "powersoftau export challange <powersoftau_0000.ptau> [challange]",
         description: "Creates a challange",
         alias: ["pte"],
         options: "-verbose|v",
         action: powersOfTawExportChallange
     },
     {
-        cmd: "powersoftaw challange contribute <challange> [response]",
+        cmd: "powersoftau challange contribute <challange> [response]",
         description: "Contribute to a challange",
         alias: ["ptcc"],
         options: "-verbose|v -entropy|e",
         action: powersOfTawChallangeContribute
     },
     {
-        cmd: "powersoftaw import <powersoftaw_old.ptaw> <response> <<powersoftaw_new.ptaw>",
-        description: "import a response to a ptaw file",
+        cmd: "powersoftau import <powersoftau_old.ptau> <response> <<powersoftau_new.ptau>",
+        description: "import a response to a ptau file",
         alias: ["pti"],
         options: "-verbose|v -nopoints -nocheck -description|d -name|n",
         action: powersOfTawImport
     },
     {
-        cmd: "powersoftaw verify <powersoftaw.ptaw>",
+        cmd: "powersoftau verify <powersoftau.ptau>",
         description: "verifies a powers of tau file",
         alias: ["ptv"],
         options: "-verbose|v",
         action: powersOfTawVerify
     },
     {
-        cmd: "powersoftaw beacon <old_powersoftaw.ptaw> <new_powersoftaw.ptaw> <beaconHash(Hex)> <numIterationsExp>",
+        cmd: "powersoftau beacon <old_powersoftau.ptau> <new_powersoftau.ptau> <beaconHash(Hex)> <numIterationsExp>",
         description: "adds a beacon",
         alias: ["ptb"],
         options: "-verbose|v -name|n",
         action: powersOfTawBeacon
     },
     {
-        cmd: "powersoftaw contribute <powersoftaw.ptaw> <new_powersoftaw.ptaw>",
+        cmd: "powersoftau contribute <powersoftau.ptau> <new_powersoftau.ptau>",
         description: "verifies a powers of tau file",
         alias: ["ptc"],
         options: "-verbose|v -name|n -entropy|e",
         action: powersOfTawContribute
     },
     {
-        cmd: "powersoftaw prepare phase2 <powersoftaw.ptaw> <new_powersoftaw.ptaw>",
+        cmd: "powersoftau prepare phase2 <powersoftau.ptau> <new_powersoftau.ptau>",
         description: "Prepares phase 2. ",
         longDescription: " This process calculates the evaluation of the Lagrange polinomials at tau for alpha*tau and beta tau",
         alias: ["pt2"],
         options: "-verbose|v",
         action: powersOfTawPreparePhase2
     },
+    {
+        cmd: "phase2 new [circuit.r1cs] [powersoftau.ptau] [circuit.zkey]",
+        description: "Creates an initial pkey file with zero contributions ",
+        alias: ["p2n"],
+        options: "-verbose|v",
+        action: phase2new
+    },
 
 ];
 
@@ -504,7 +513,7 @@ async function solidityGenCall(params, options) {
 
 async function powersOfTawNew(params, options) {
     let power;
-    let ptawName;
+    let ptauName;
 
     power = parseInt(params[0]);
     if ((power<1) || (power>28)) {
@@ -512,19 +521,19 @@ async function powersOfTawNew(params, options) {
     }
 
     if (params.length < 2) {
-        ptawName = "powersOfTaw" + power + "_0000.ptaw";
+        ptauName = "powersOfTaw" + power + "_0000.ptau";
     } else {
-        ptawName = params[1];
+        ptauName = params[1];
     }
 
-    return await powersOfTaw.newAccumulator(bn128, power, ptawName, options.verbose);
+    return await powersOfTaw.newAccumulator(bn128, power, ptauName, options.verbose);
 }
 
 async function powersOfTawExportChallange(params, options) {
-    let ptawName;
+    let ptauName;
     let challangeName;
 
-    ptawName = params[0];
+    ptauName = params[0];
 
     if (params.length < 2) {
         challangeName = "challange";
@@ -532,7 +541,7 @@ async function powersOfTawExportChallange(params, options) {
         challangeName = params[1];
     }
 
-    return await powersOfTaw.exportChallange(ptawName, challangeName, options.verbose);
+    return await powersOfTaw.exportChallange(ptauName, challangeName, options.verbose);
 }
 
 
@@ -623,3 +632,30 @@ async function powersOfTawPreparePhase2(params, options) {
     return await powersOfTaw.preparePhase2(oldPtauName, newPtauName, options.verbose);
 }
 
+
+// phase2 new <circuit.r1cs> <powersoftau.ptau> <circuit.zkey>
+async function phase2new(params, options) {
+    let r1csName;
+    let ptauName;
+    let zkeyName;
+
+    if (params.length < 1) {
+        r1csName = "circuit.r1cs";
+    } else {
+        r1csName = params[0];
+    }
+
+    if (params.length < 2) {
+        ptauName = "powersoftau.ptau";
+    } else {
+        ptauName = params[1];
+    }
+
+    if (params.length < 2) {
+        zkeyName = "circuit.zkey";
+    } else {
+        zkeyName = params[2];
+    }
+
+    return phase2.new(r1csName, ptauName, zkeyName, options.verbose);
+}
diff --git a/src/binfileutils.js b/src/binfileutils.js
index c4db735..16a7c72 100644
--- a/src/binfileutils.js
+++ b/src/binfileutils.js
@@ -88,7 +88,7 @@ async function endReadSection(fd, noCheck) {
 
 async function writeBigInt(fd, n, n8) {
     const buff = new Uint8Array(n8);
-    Scalar.toRprLE(buff, 0, n);
+    Scalar.toRprLE(buff, 0, n, n8);
     await fd.write(buff);
 }
 
diff --git a/src/phase2.js b/src/phase2.js
new file mode 100644
index 0000000..3bd56ab
--- /dev/null
+++ b/src/phase2.js
@@ -0,0 +1,3 @@
+
+
+module.exports.new = require("./phase2_new.js");
diff --git a/src/phase2_new.js b/src/phase2_new.js
new file mode 100644
index 0000000..b4ca2cc
--- /dev/null
+++ b/src/phase2_new.js
@@ -0,0 +1,191 @@
+
+const loadR1cs = require("r1csfile").load;
+const utils = require("./powersoftau_utils");
+const binFileUtils = require("./binfileutils");
+const writeZKey = require("./zkeyfile").write;
+const assert = require("assert");
+
+
+function log2( V )
+{
+    return( ( ( V & 0xFFFF0000 ) !== 0 ? ( V &= 0xFFFF0000, 16 ) : 0 ) | ( ( V & 0xFF00FF00 ) !== 0 ? ( V &= 0xFF00FF00, 8 ) : 0 ) | ( ( V & 0xF0F0F0F0 ) !== 0 ? ( V &= 0xF0F0F0F0, 4 ) : 0 ) | ( ( V & 0xCCCCCCCC ) !== 0 ? ( V &= 0xCCCCCCCC, 2 ) : 0 ) | ( ( V & 0xAAAAAAAA ) !== 0 ) );
+}
+
+
+module.exports  = async function phase2new(r1csName, ptauName, zkeyName) {
+
+    const r1cs = await loadR1cs(r1csName, true);
+
+    const {fd: ptauFd, sections} = await binFileUtils.readBinFile(ptauName, "ptau", 1);
+    const {curve, power} = await utils.readPTauHeader(ptauFd, sections);
+
+    if (r1cs.prime != curve.r) {
+        console.log("r1cs curve does not match powers of tau ceremony curve");
+        return -1;
+    }
+
+    const cirPower = log2(r1cs.nConstraints + r1cs.nPubInputs + r1cs.nOutputs +1 -1) +1;
+
+    if (cirPower > power) {
+        console.log(`circuit too big for this power of tau ceremony. ${r1cs.nConstraints} > 2**${power}`);
+        return -1;
+    }
+
+    if (!sections[12]) {
+        console.log("Powers of tau is not prepared.");
+        return -1;
+    }
+
+    const zKey = {
+
+        nPublic: r1cs.nOutputs + r1cs.nPubInputs,
+        nVars: r1cs.nVars,
+        q: curve.q,
+        r: curve.r,
+        domainBits: cirPower,
+        domainSize: 1 << cirPower
+
+    };
+
+    const linc = 1 << (power - cirPower);
+
+    calculatePolinomials(curve, zKey,r1cs);
+
+    zKey.A = new Array(r1cs.nVars);
+    zKey.B1 = new Array(r1cs.nVars);
+    zKey.B2 = new Array(r1cs.nVars);
+    zKey.C = new Array(r1cs.nVars);
+    zKey.IC = new Array(zKey.nPublic+1);
+    for (let i=0; i<r1cs.nVars; i++) {
+        zKey.A[i] = curve.G1.zero;
+        zKey.B1[i] = curve.G1.zero;
+        zKey.B2[i] = curve.G2.zero;
+        if (i>zKey.nPublic) {
+            zKey.C[i] = curve.G1.zero;
+        } else {
+            zKey.IC[i] = curve.G1.zero;
+        }
+    }
+    for (let i=0; i<zKey.ccoefs.length; i++) {
+        const c = zKey.ccoefs[i];
+        let CIC;
+        if (c.matrix == 0) {
+            const l1 = await readEvaluation("lTauG1", c.constraint);
+            const l2 = await readEvaluation("lBetaTauG1", c.constraint);
+            zKey.A[c.signal] =
+                curve.G1.add(
+                    zKey.A[c.signal],
+                    curve.G1.mulScalar(l1, c.value)
+                );
+            CIC = curve.G1.mulScalar(l2, c.value);
+        } else if (c.matrix == 1) {
+            const l1 = await readEvaluation("lTauG1", c.constraint);
+            const l2 = await readEvaluation("lTauG2", c.constraint);
+            const l3 = await readEvaluation("lAlphaTauG1", c.constraint);
+            zKey.B1[c.signal] =
+                curve.G1.add(
+                    zKey.B1[c.signal],
+                    curve.G1.mulScalar(l1, c.value)
+                );
+            zKey.B2[c.signal] =
+                curve.G2.add(
+                    zKey.B2[c.signal],
+                    curve.G2.mulScalar(l2, c.value)
+                );
+            CIC = curve.G1.mulScalar(l3, c.value);
+        } else if (c.matrix == 2) {
+            const l1 = await readEvaluation("lTauG1", c.constraint);
+            CIC = curve.G1.mulScalar(l1, c.value);
+        } else {
+            assert(false);
+        }
+
+        if (c.signal <= zKey.nPublic) {
+            zKey.IC[c.signal] =
+                curve.G1.add(
+                    zKey.IC[c.signal],
+                    CIC
+                );
+        } else {
+            zKey.C[c.signal] =
+                curve.G1.add(
+                    zKey.C[c.signal],
+                    CIC
+                );
+        }
+    }
+
+
+    zKey.hExps = new Array(zKey.domainSize-1);
+    for (let i=0; i< zKey.domainSize; i++) {
+        const t1 = await readEvaluation("tauG1", i);
+        const t2 = await readEvaluation("tauG1", i+zKey.domainSize);
+        zKey.hExps[i] = curve.G1.add(t1, t2);
+    }
+
+    zKey.vk_alfa_1 = await readEvaluation("alphaTauG1", 0);
+    zKey.vk_beta_1 = await readEvaluation("betaTauG1", 0);
+    zKey.vk_delta_1 = curve.G1.g;
+    zKey.vk_beta_2 = await readEvaluation("betaG2", 0);
+    zKey.vk_gamma_2 = curve.G2.g;
+    zKey.vk_delta_2 = curve.G2.g;
+
+    await writeZKey(zkeyName, zKey);
+
+    return 0;
+
+    async function readEvaluation(sectionName, idx) {
+        let o;
+        let G;
+        switch (sectionName) {
+        case "tauG1": o = sections[2][0].p; G = curve.G1;  break;
+        case "tauG2": o = sections[3][0].p; G = curve.G2;  break;
+        case "alphaTauG1": o = sections[4][0].p; G = curve.G1;  break;
+        case "betaTauG1": o = sections[5][0].p; G = curve.G1;  break;
+        case "betaG2": o = sections[6][0].p; G = curve.G2;  break;
+        case "lTauG1": o = sections[12][0].p; G = curve.G1;  break;
+        case "lTauG2": o = sections[13][0].p; G = curve.G2; break;
+        case "lAlphaTauG1": o = sections[14][0].p; G = curve.G1; break;
+        case "lBetaTauG1": o = sections[15][0].p; G = curve.G1; break;
+        }
+        const sG = G.F.n8*2;
+        ptauFd.pos = o + sG*idx*linc;
+        const buff = await ptauFd.read(sG);
+        return G.fromRprLEM(buff, 0);
+    }
+
+};
+
+
+function calculatePolinomials(curve, zKey, r1cs) {
+
+    zKey.ccoefs = [];
+    for (let m=0; m<2; m++) {
+        for (let c=0; c<r1cs.nConstraints; c++) {
+            const signals = Object.keys(r1cs.constraints[c][m]);
+            signals.forEach( (s) => {
+                zKey.ccoefs.push({
+                    matrix: m,
+                    constraint: c,
+                    signal: s,
+                    value: r1cs.constraints[c][m][s]
+                });
+            });
+        }
+    }
+
+    /**
+     * add and process the constraints
+     *     input_i * 0 = 0
+     * to ensure soundness of input consistency
+     */
+    for (let i = 0; i < r1cs.nPubInputs + r1cs.nOutputs + 1; ++i)
+    {
+        zKey.ccoefs.push({
+            matrix: 0,
+            constraint: r1cs.nConstraints + i,
+            signal: i,
+            value: curve.Fr.one
+        });
+    }
+}
diff --git a/src/powersoftaw.js b/src/powersoftau.js
similarity index 100%
rename from src/powersoftaw.js
rename to src/powersoftau.js
diff --git a/src/powersoftau_verify.js b/src/powersoftau_verify.js
index 470d07f..f60a6d6 100644
--- a/src/powersoftau_verify.js
+++ b/src/powersoftau_verify.js
@@ -3,20 +3,21 @@ const utils = require("./powersoftau_utils");
 const keyPair = require("./keypair");
 const assert = require("assert");
 const crypto = require("crypto");
-const buildTaskManager = require("./taskmanager");
 const binFileUtils = require("./binfileutils");
 const ChaCha = require("ffjavascript").ChaCha;
 
-function sameRatio(curve, g1s, g1sx, g2s, g2sx) {
+async function sameRatio(curve, g1s, g1sx, g2s, g2sx) {
     if (curve.G1.isZero(g1s)) return false;
     if (curve.G1.isZero(g1sx)) return false;
     if (curve.G2.isZero(g2s)) return false;
     if (curve.G2.isZero(g2sx)) return false;
-    return curve.F12.eq(curve.pairing(g1s, g2sx), curve.pairing(g1sx, g2s));
+    // return curve.F12.eq(curve.pairing(g1s, g2sx), curve.pairing(g1sx, g2s));
+    const res = await curve.pairingEq(g1s, g2sx, curve.G1.neg(g1sx), g2s);
+    return res;
 }
 
-function verifyContribution(curve, cur, prev) {
-
+async function verifyContribution(curve, cur, prev) {
+    let sr;
     if (cur.type == 1) {    // Verify the beacon.
         const beaconKey = utils.keyFromBeacon(curve, prev.nextChallange, cur.beaconHash, cur.numIterationsExp);
 
@@ -64,42 +65,50 @@ function verifyContribution(curve, cur, prev) {
     cur.key.alpha.g2_sp = keyPair.getG2sp(1, prev.nextChallange, cur.key.alpha.g1_s, cur.key.alpha.g1_sx);
     cur.key.beta.g2_sp = keyPair.getG2sp(2, prev.nextChallange, cur.key.beta.g1_s, cur.key.beta.g1_sx);
 
-    if (!sameRatio(curve, cur.key.tau.g1_s, cur.key.tau.g1_sx, cur.key.tau.g2_sp, cur.key.tau.g2_spx)) {
+    sr = await sameRatio(curve, cur.key.tau.g1_s, cur.key.tau.g1_sx, cur.key.tau.g2_sp, cur.key.tau.g2_spx);
+    if (sr !== true) {
         console.log("INVALID key (tau) in challange #"+cur.id);
         return false;
     }
 
-    if (!sameRatio(curve, cur.key.alpha.g1_s, cur.key.alpha.g1_sx, cur.key.alpha.g2_sp, cur.key.alpha.g2_spx)) {
+    sr = await sameRatio(curve, cur.key.alpha.g1_s, cur.key.alpha.g1_sx, cur.key.alpha.g2_sp, cur.key.alpha.g2_spx);
+    if (sr !== true) {
         console.log("INVALID key (alpha) in challange #"+cur.id);
         return false;
     }
 
-    if (!sameRatio(curve, cur.key.beta.g1_s, cur.key.beta.g1_sx, cur.key.beta.g2_sp, cur.key.beta.g2_spx)) {
+    sr = await sameRatio(curve, cur.key.beta.g1_s, cur.key.beta.g1_sx, cur.key.beta.g2_sp, cur.key.beta.g2_spx);
+    if (sr !== true) {
         console.log("INVALID key (beta) in challange #"+cur.id);
         return false;
     }
 
-    if (!sameRatio(curve, prev.tauG1, cur.tauG1, cur.key.tau.g2_sp, cur.key.tau.g2_spx)) {
+    sr = await sameRatio(curve, prev.tauG1, cur.tauG1, cur.key.tau.g2_sp, cur.key.tau.g2_spx);
+    if (sr !== true) {
         console.log("INVALID tau*G1. challange #"+cur.id+" It does not follow the previous contribution");
         return false;
     }
 
-    if (!sameRatio(curve,  cur.key.tau.g1_s, cur.key.tau.g1_sx, prev.tauG2, cur.tauG2,)) {
+    sr = await sameRatio(curve,  cur.key.tau.g1_s, cur.key.tau.g1_sx, prev.tauG2, cur.tauG2);
+    if (sr !== true) {
         console.log("INVALID tau*G2. challange #"+cur.id+" It does not follow the previous contribution");
         return false;
     }
 
-    if (!sameRatio(curve, prev.alphaG1, cur.alphaG1, cur.key.alpha.g2_sp, cur.key.alpha.g2_spx)) {
+    sr = await sameRatio(curve, prev.alphaG1, cur.alphaG1, cur.key.alpha.g2_sp, cur.key.alpha.g2_spx);
+    if (sr !== true) {
         console.log("INVALID alpha*G1. challange #"+cur.id+" It does not follow the previous contribution");
         return false;
     }
 
-    if (!sameRatio(curve, prev.betaG1, cur.betaG1, cur.key.beta.g2_sp, cur.key.beta.g2_spx)) {
+    sr = await sameRatio(curve, prev.betaG1, cur.betaG1, cur.key.beta.g2_sp, cur.key.beta.g2_spx);
+    if (sr !== true) {
         console.log("INVALID beta*G1. challange #"+cur.id+" It does not follow the previous contribution");
         return false;
     }
 
-    if (!sameRatio(curve,  cur.key.beta.g1_s, cur.key.beta.g1_sx, prev.betaG2, cur.betaG2,)) {
+    sr = await sameRatio(curve,  cur.key.beta.g1_s, cur.key.beta.g1_sx, prev.betaG2, cur.betaG2);
+    if (sr !== true) {
         console.log("INVALID beta*G2. challange #"+cur.id+"It does not follow the previous contribution");
         return false;
     }
@@ -108,6 +117,7 @@ function verifyContribution(curve, cur, prev) {
 }
 
 async function verify(tauFilename, verbose) {
+    let sr;
     await Blake2b.ready();
 
     const {fd, sections} = await binFileUtils.readBinFile(tauFilename, "ptau", 1);
@@ -141,7 +151,7 @@ async function verify(tauFilename, verbose) {
     }
     const curContr = contrs[contrs.length-1];
     if (verbose) console.log("Validating contribution #"+contrs[contrs.length-1].id);
-    const res = verifyContribution(curve, curContr,prevContr, verbose);
+    const res = await verifyContribution(curve, curContr,prevContr, verbose);
     if (!res) return false;
 
 
@@ -156,7 +166,8 @@ async function verify(tauFilename, verbose) {
     // Verify Section tau*G1
     if (verbose) console.log("Verifying powers in tau*G1 section");
     const rTau1 = await processSection(2, "G1", "tauG1", (1 << power)*2-1, [0, 1]);
-    if (!sameRatio(curve, rTau1.R1, rTau1.R2, curve.G2.g, curContr.tauG2)) {
+    sr = await sameRatio(curve, rTau1.R1, rTau1.R2, curve.G2.g, curContr.tauG2);
+    if (sr !== true) {
         console.log("tauG1 section. Powers do not match");
         return false;
     }
@@ -174,7 +185,8 @@ async function verify(tauFilename, verbose) {
     // Verify Section tau*G2
     if (verbose) console.log("Verifying powers in tau*G2 section");
     const rTau2 = await processSection(3, "G2", "tauG2", 1 << power, [0, 1]);
-    if (!sameRatio(curve, curve.G1.g, curContr.tauG1, rTau2.R1, rTau2.R2)) {
+    sr = await sameRatio(curve, curve.G1.g, curContr.tauG1, rTau2.R1, rTau2.R2);
+    if (sr !== true) {
         console.log("tauG2 section. Powers do not match");
         return false;
     }
@@ -190,7 +202,8 @@ async function verify(tauFilename, verbose) {
     // Verify Section alpha*tau*G1
     if (verbose) console.log("Verifying powers in alpha*tau*G1 section");
     const rAlphaTauG1 = await processSection(4, "G1", "alphatauG1", 1 << power, [0]);
-    if (!sameRatio(curve, rAlphaTauG1.R1, rAlphaTauG1.R2, curve.G2.g, curContr.tauG2)) {
+    sr = await sameRatio(curve, rAlphaTauG1.R1, rAlphaTauG1.R2, curve.G2.g, curContr.tauG2);
+    if (sr !== true) {
         console.log("alphaTauG1 section. Powers do not match");
         return false;
     }
@@ -202,7 +215,8 @@ async function verify(tauFilename, verbose) {
     // Verify Section beta*tau*G1
     if (verbose) console.log("Verifying powers in beta*tau*G1 section");
     const rBetaTauG1 = await processSection(5, "G1", "betatauG1", 1 << power, [0]);
-    if (!sameRatio(curve, rBetaTauG1.R1, rBetaTauG1.R2, curve.G2.g, curContr.tauG2)) {
+    sr = await sameRatio(curve, rBetaTauG1.R1, rBetaTauG1.R2, curve.G2.g, curContr.tauG2);
+    if (sr !== true) {
         console.log("betaTauG1 section. Powers do not match");
         return false;
     }
@@ -238,7 +252,7 @@ async function verify(tauFilename, verbose) {
     for (let i = contrs.length-2; i>=0; i--) {
         const curContr = contrs[i];
         const prevContr =  (curContr>0) ? contrs[i-1] : initialContribution;
-        verifyContribution(curve, curContr, prevContr);
+        await verifyContribution(curve, curContr, prevContr);
         printContribution(curContr, prevContr);
     }
     console.log("-----------------------------------------------------");
diff --git a/src/zkeyfile.js b/src/zkeyfile.js
index cae1144..2192024 100644
--- a/src/zkeyfile.js
+++ b/src/zkeyfile.js
@@ -32,10 +32,18 @@ const Scalar = require("ffjavascript").Scalar;
 const F1Field = require("ffjavascript").F1Field;
 const assert = require("assert");
 const binFileUtils = require("./binfileutils");
+const bn128 = require("ffjavascript").bn128;
 
 module.exports.write = async function writeZKey(fileName, zkey) {
 
-    const fd = await binFileUtils.createOverride(fileName,"zkey", 6, 1);
+    let curve;
+    if (Scalar.eq(zkey.q, bn128.q)) {
+        curve = bn128;
+    } else {
+        assert(false, fd.fileName +": Curve not supported");
+    }
+
+    const fd = await binFileUtils.createBinFile(fileName,"zkey", 1, 9);
 
     // Write the header
     ///////////
@@ -48,20 +56,17 @@ module.exports.write = async function writeZKey(fileName, zkey) {
 
     await binFileUtils.startWriteSection(fd, 2);
     const primeQ = zkey.q;
-    const Fq = new F1Field(zkey.q);
     const n8q = (Math.floor( (Scalar.bitLength(primeQ) - 1) / 64) +1)*8;
-    const Rq = Scalar.mod(Scalar.shl(1, n8q*8), primeQ);
 
     const primeR = zkey.r;
-    const Fr = new F1Field(zkey.r);
     const n8r = (Math.floor( (Scalar.bitLength(primeR) - 1) / 64) +1)*8;
     const Rr = Scalar.mod(Scalar.shl(1, n8r*8), primeR);
     const R2r = Scalar.mod(Scalar.mul(Rr,Rr), primeR);
 
     await fd.writeULE32(n8q);
-    await binFileUtils.writeBigInt(primeQ, n8q);
+    await binFileUtils.writeBigInt(fd, primeQ, n8q);
     await fd.writeULE32(n8r);
-    await binFileUtils.writeBigInt(primeR, n8r);
+    await binFileUtils.writeBigInt(fd, primeR, n8r);
     await fd.writeULE32(zkey.nVars);                         // Total number of bars
     await fd.writeULE32(zkey.nPublic);                       // Total number of public vars (not including ONE)
     await fd.writeULE32(zkey.domainSize);                  // domainSize
@@ -98,24 +103,43 @@ module.exports.write = async function writeZKey(fileName, zkey) {
     await binFileUtils.endWriteSection(fd);
 
 
-    // Write A B1 B2 C points
+
+    // Write A
     ///////////
     await binFileUtils.startWriteSection(fd, 5);
     for (let i=0; i<zkey.nVars; i++) {
         await writePointG1(zkey.A[i]);
-        await writePointG1(zkey.B1[i]);
-        await writePointG2(zkey.B2[i]);
-        if (i<=zkey.nPublic) {
-            await writePointG1_zero();
-        } else {
-            await writePointG1(zkey.C[i]);
-        }
     }
     await binFileUtils.endWriteSection(fd);
 
-    // Write H points
+    // Write B1
     ///////////
     await binFileUtils.startWriteSection(fd, 6);
+    for (let i=0; i<zkey.nVars; i++) {
+        await writePointG1(zkey.B1[i]);
+    }
+    await binFileUtils.endWriteSection(fd);
+
+    // Write B2
+    ///////////
+    await binFileUtils.startWriteSection(fd, 7);
+    for (let i=0; i<zkey.nVars; i++) {
+        await writePointG2(zkey.B2[i]);
+    }
+    await binFileUtils.endWriteSection(fd);
+
+    // Write C
+    ///////////
+    await binFileUtils.startWriteSection(fd, 8);
+    for (let i=zkey.nPublic+1; i<zkey.nVars; i++) {
+        await writePointG1(zkey.C[i]);
+    }
+    await binFileUtils.endWriteSection(fd);
+
+
+    // Write H points
+    ///////////
+    await binFileUtils.startWriteSection(fd, 9);
     for (let i=0; i<zkey.domainSize; i++) {
         await writePointG1(zkey.hExps[i]);
     }
@@ -130,41 +154,16 @@ module.exports.write = async function writeZKey(fileName, zkey) {
         await binFileUtils.writeBigInt(fd, n, n8r);
     }
 
-    async function writeFq(n) {
-        // Convert to montgomery
-        n = Scalar.mod( Scalar.mul(n, Rq), primeQ);
-
-        await binFileUtils.writeBigInt(fd, n, n8q);
-    }
-
     async function writePointG1(p) {
-        if (Fq.isZero(p[2])) {
-            await writeFq(0);
-            await writeFq(0);
-        } else {
-            await writeFq(p[0]);
-            await writeFq(p[1]);
-        }
-    }
-
-    async function writePointG1_zero() {
-        await writeFq(0);
-        await writeFq(0);
+        const buff = new Uint8Array(curve.G1.F.n8*2);
+        curve.G1.toRprLEM(buff, 0, p);
+        await fd.write(buff);
     }
 
     async function writePointG2(p) {
-        if (Fq.isZero(p[2][0]) && Fq.isZero(p[2][1])) {
-            await writeFq(Fq.e(0));
-            await writeFq(Fq.e(0));
-            await writeFq(Fq.e(0));
-            await writeFq(Fq.e(0));
-
-        } else {
-            await writeFq(p[0][0]);
-            await writeFq(p[0][1]);
-            await writeFq(p[1][0]);
-            await writeFq(p[1][1]);
-        }
+        const buff = new Uint8Array(curve.G2.F.n8*2);
+        curve.G2.toRprLEM(buff, 0, p);
+        await fd.write(buff);
     }
 };
 
@@ -197,6 +196,12 @@ module.exports.read = async function readZKey(fileName) {
     const Rri = Fr.inv(Rr);
     const Rri2 = Fr.mul(Rri, Rri);
 
+    let curve;
+    if (Scalar.eq(zkey.q, bn128.q)) {
+        curve = bn128;
+    } else {
+        assert(false, fd.fileName +": Curve not supported");
+    }
 
     zkey.nVars = await fd.readULE32();
     zkey.nPublic = await fd.readULE32();
@@ -240,32 +245,55 @@ module.exports.read = async function readZKey(fileName) {
     }
     await binFileUtils.endReadSection(fd);
 
-    // Read A B1 B2 C points
+    // Read A points
     ///////////
     await binFileUtils.startReadUniqueSection(fd, sections, 5);
     zkey.A = [];
-    zkey.B1 = [];
-    zkey.B2 = [];
-    zkey.C = [];
     for (let i=0; i<zkey.nVars; i++) {
         const A = await readG1();
-        const B1 = await readG1();
-        const B2 = await readG2();
-        const C = await readG1();
-
-        zkey.A.push(A);
-        zkey.B1.push(B1);
-        zkey.B2.push(B2);
-        zkey.C.push(C);
-        if (i<= zkey.nPublic) {
-            assert(Fr.isZero(C[2]), "C value for public is not zero");
-        }
+        zkey.A[i] = A;
     }
     await binFileUtils.endReadSection(fd);
 
-    // Read H points
+
+    // Read B1
     ///////////
     await binFileUtils.startReadUniqueSection(fd, sections, 6);
+    zkey.B1 = [];
+    for (let i=0; i<zkey.nVars; i++) {
+        const B1 = await readG1();
+
+        zkey.B1[i] = B1;
+    }
+    await binFileUtils.endReadSection(fd);
+
+
+    // Read B2 points
+    ///////////
+    await binFileUtils.startReadUniqueSection(fd, sections, 7);
+    zkey.B2 = [];
+    for (let i=0; i<zkey.nVars; i++) {
+        const B2 = await readG2();
+        zkey.B2[i] = B2;
+    }
+    await binFileUtils.endReadSection(fd);
+
+
+    // Read C points
+    ///////////
+    await binFileUtils.startReadUniqueSection(fd, sections, 8);
+    zkey.C = [];
+    for (let i=zkey.nPublic+1; i<zkey.nVars; i++) {
+        const C = await readG1();
+
+        zkey.C[i] = C;
+    }
+    await binFileUtils.endReadSection(fd);
+
+
+    // Read H points
+    ///////////
+    await binFileUtils.startReadUniqueSection(fd, sections, 9);
     zkey.hExps = [];
     for (let i=0; i<zkey.domainSize; i++) {
         const H = await readG1();
@@ -277,36 +305,19 @@ module.exports.read = async function readZKey(fileName) {
 
     return zkey;
 
-    async function readFq() {
-        const n = await binFileUtils.readBigInt(fd, n8q);
-        return Fq.mul(n, Rqi);
-    }
-
     async function readFr2() {
         const n = await binFileUtils.readBigInt(fd, n8r);
         return Fr.mul(n, Rri2);
     }
 
     async function readG1() {
-        const x = await readFq();
-        const y = await readFq();
-        if (Fq.isZero(x) && Fq.isZero(y)) {
-            return [Fq.e(0), Fq.e(1), Fq.e(0)];
-        } else {
-            return [x , y, Fq.e(1)];
-        }
+        const buff = await fd.read(curve.G1.F.n8*2);
+        return curve.G1.fromRprLEM(buff, 0);
     }
 
     async function readG2() {
-        const xa = await readFq();
-        const xb = await readFq();
-        const ya = await readFq();
-        const yb = await readFq();
-        if (Fq.isZero(xa) && Fq.isZero(xb) && Fq.isZero(ya) && Fq.isZero(yb)) {
-            return [[Fq.e(0),Fq.e(0)],[Fq.e(1),Fq.e(0)], [Fq.e(0),Fq.e(0)]];
-        } else {
-            return [[xa, xb],[ya, yb], [Fq.e(1),Fq.e(0)]];
-        }
+        const buff = await fd.read(curve.G2.F.n8*2);
+        return curve.G2.fromRprLEM(buff, 0);
     }